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Guan J, Liu T, Yang K, Chen H. Dried fruit intake and lower risk of type 2 diabetes: a two-sample mendelian randomization study. Nutr Metab (Lond) 2024; 21:46. [PMID: 38987806 PMCID: PMC11234600 DOI: 10.1186/s12986-024-00813-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Accepted: 06/18/2024] [Indexed: 07/12/2024] Open
Abstract
BACKGROUND Previous studies have shown controversy about whether dried fruit intake is associated with type 2 diabetes. This study aimed to examine the potential causal effect of dried fruit intake on type 2 diabetes by conducting a two-sample Mendelian randomization study. METHODS We used genome-wide association study (GWAS) summary statistics for MR analysis to explore the causal association of dried fruit intake with T2D. The inverse-variance weighted (IVW) method was used as the main analytical method for MR analysis. In addition, the MR-Egger method and the weighted median method were applied to supplement the IVW method. Furthermore, Cochrane's Q test, MR-Egger intercept test, and leave-one-out analysis were used to perform sensitivity analysis. The funnel plot was used to assess publication bias. RESULTS The results from the IVW analysis indicated that dried fruit intake could reduce the risk of T2D [odds ratio (OR) = 0.392, 95% confidence interval (CI): 0.241-0.636, p-value = 0.0001]. In addition, the result of additional method Weighted median is parallel to the effects estimated by IVW. Furthermore, the sensitivity analysis illustrates that our MR analysis was unaffected by heterogeneity and horizontal pleiotropy. Finally, the results of the leave-one-out method showed the robustness of our MR results. And the funnel plot shows a symmetrical distribution. CONCLUSION Our study provides evidence for the benefits of dried fruit intake on T2D. Therefore, a reasonable consumption of dried fruit may provide primary prevention.
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Affiliation(s)
- Jianbin Guan
- Honghui Hospital, Xi'an Jiaotong University, Xi'an, Shannxi, 710054, China
| | - Tao Liu
- Honghui Hospital, Xi'an Jiaotong University, Xi'an, Shannxi, 710054, China
| | - Kaitan Yang
- Honghui Hospital, Xi'an Jiaotong University, Xi'an, Shannxi, 710054, China.
- Truma Rehabilitation Department, Honghui Hospital, Xi'an Jiaotong University, Xi'an, Shannxi, 710054, China.
| | - Hao Chen
- Honghui Hospital, Xi'an Jiaotong University, Xi'an, Shannxi, 710054, China.
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Li X, Zeng J, Chen B, Yan Q, Cui Y, Xu W, Zhang X, Xu S. Daily higher tea consumption is associated with a reduced risk of type 2 diabetes: A cohort study and updated systematic review and meta-analysis. Nutr Res 2023; 118:116-127. [PMID: 37647847 DOI: 10.1016/j.nutres.2023.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 07/31/2023] [Accepted: 08/06/2023] [Indexed: 09/01/2023]
Abstract
Tea is abundant in phytochemicals (such as polyphenols and theaflavins), which have a hypoglycemic effect. Previous studies investigating the relationship between tea consumption and the risk of type 2 diabetes mellitus (T2DM) have yielded inconsistent results. We hypothesized that tea consumption would be associated with a reduced risk of T2DM. This cohort study used data from the China Health and Nutrition Survey, involving a total of 5199 participants initially recruited in 1997 and subsequently followed until 2009. Consumption of any variety of tea was tracked using structured questionnaires, and T2DM was diagnosed according to the American Diabetes Association's criteria. We also performed a systematic literature search of PubMed, Web of Science, and EMBASE for publications through September 2021, including 19 cohort studies comprising 1,076,311 participants. In our cohort study, the logistic regression model showed a relative risk (RR) of T2DM among tea drinkers of 1.02 (95% confidence interval [CI], 0.82-1.28) compared with non-tea drinkers. Although our updated meta-analysis showed no significant association between tea consumption and T2DM on the whole (pooled RR of 0.96 [0.91-1.00]), compared with the non-tea-drinking group, participants consuming 4 or more cups of tea per day had a 17% reduced risk of T2DM, with an RR of 0.83 (95% CI, 0.76-0.90). These data support our hypothesis that tea consumption at higher doses (e.g., ≥4 cups/day) is associated with a reduced risk of T2DM.
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Affiliation(s)
- Xiaying Li
- College of Medicine, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Jingjing Zeng
- Center for Clinical Evidence-Based and Translational Medicine, Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, Hubei, China
| | - Bo Chen
- Center for Clinical Evidence-Based and Translational Medicine, Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, Hubei, China
| | - Qiongjie Yan
- Center for Clinical Evidence-Based and Translational Medicine, Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, Hubei, China
| | - Yuze Cui
- Center for Clinical Evidence-Based and Translational Medicine, Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, Hubei, China
| | - Wenlei Xu
- Center for Clinical Evidence-Based and Translational Medicine, Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, Hubei, China
| | - Xiaotong Zhang
- Department of Nephrology, Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, Hubei, China
| | - Shaoyong Xu
- Center for Clinical Evidence-Based and Translational Medicine, Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, Hubei, China; Department of Endocrinology, Xiangyang Central Hospital Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, Hubei, China.
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Jacobo Cejudo MG, Ochoa-Rosales C, Ahmadizar F, Kavousi M, Geleijnse JM, Voortman T. The healthy beverage index is not associated with insulin resistance, prediabetes and type 2 diabetes risk in the Rotterdam Study. Eur J Nutr 2023; 62:3021-3031. [PMID: 37488428 PMCID: PMC10468439 DOI: 10.1007/s00394-023-03209-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 07/10/2023] [Indexed: 07/26/2023]
Abstract
PURPOSE Whether beverage quality affects changes in glycaemic traits and type 2 diabetes (T2D) risk is unknown. We examined associations of a previously developed Healthy Beverage Index (HBI) with insulin resistance, and risk of prediabetes and T2D. METHODS We included 6769 participants (59% female, 62.0 ± 7.8 years) from the Rotterdam Study cohort free of diabetes at baseline. Diet was assessed using food-frequency questionnaires at baseline. The HBI included 10 components (energy from beverages, meeting fluid requirements, water, coffee and tea, low-fat milk, diet drinks, juices, alcohol, full-fat milk, and sugar-sweetened beverages), with a total score ranging from 0 to 100. A higher score represents a healthier beverage pattern. Data on study outcomes were available from 1993 to 2015. Multivariable linear mixed models and Cox proportional-hazards regression models were used to examine associations of the HBI (per 10 points increment) with two measurements of HOMA-IR (a proxy for insulin resistance), and risk of prediabetes and T2D. RESULTS During follow-up, we documented 1139 prediabetes and 784 T2D cases. Mean ± SD of the HBI was 66.8 ± 14.4. Higher HBI score was not associated with HOMA-IR (β: 0.003; 95% CI - 0.007, 0.014), or with risk of prediabetes (HR: 1.01; 95% CI 0.97, 1.06), or T2D (HR: 1.01; 95% CI 0.96, 1.07). CONCLUSION Our findings suggest no major role for overall beverage intake quality assessed with the HBI in insulin resistance, prediabetes and T2D incidence. The HBI may not be an adequate tool to assess beverage intake quality in our population.
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Affiliation(s)
- Maria G. Jacobo Cejudo
- Division of Human Nutrition and Health, Wageningen University, PO Box 17, 6700 AA Wageningen, The Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Carolina Ochoa-Rosales
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
- Latin American Brain Health Institute (BrainLat), Universidad Adolfo Ibáñez, Santiago, Chile
| | - Fariba Ahmadizar
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
- Department of Data Science & Biostatistics, Julius Global Health, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Maryam Kavousi
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Johanna M. Geleijnse
- Division of Human Nutrition and Health, Wageningen University, PO Box 17, 6700 AA Wageningen, The Netherlands
| | - Trudy Voortman
- Division of Human Nutrition and Health, Wageningen University, PO Box 17, 6700 AA Wageningen, The Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
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Tsarna E, Eleftheriades A, Tsomi E, Ziogou G, Vakas P, Panoskaltsis T, Christopoulos P. The Role of Diet during Pregnancy in Protecting against Gestational Diabetes Mellitus in a Population with Mediterranean Dietary Habits: A Cross-Sectional Study. J Clin Med 2023; 12:jcm12051857. [PMID: 36902644 PMCID: PMC10003761 DOI: 10.3390/jcm12051857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 02/20/2023] [Accepted: 02/24/2023] [Indexed: 03/02/2023] Open
Abstract
Gestational diabetes mellitus (GDM) is a common metabolic disorder among pregnant women. Dietary habits during pregnancy might alter the risk of GDM development, and populations following the Mediterranean diet are relatively understudied. This was a cross-sectional, observational study of 193 low-risk women admitted to a private maternity hospital in Greece to give birth. Food frequency data on specific food categories, selected based on previous research, were analyzed. Logistic regression models, both crude and adjusted for maternal age, body mass index before pregnancy, and gestational weight gain, were fitted. We observed no association of carbohydrate-rich meals, sweets, soft drinks, coffee, rice, pasta, bread and crackers, potatoes, lentils, and juices with GDM diagnosis. Cereals (crude p = 0.045, adjusted p = 0.095) and fruits and vegetables (crude p = 0.07, adjusted p = 0.04) appeared to have a protective effect against GDM, while frequent tea consumption was linked to higher risk of GDM development (crude p = 0.067, adjusted p = 0.035). These results strengthen previously identified associations and underline the importance and potential impact of changing dietary habits even during pregnancy in adjusting one's risk of metabolic pregnancy complications, such as GDM. The importance of healthy dietary habits is highlighted, with the goal of raising awareness amongst obstetric care specialists regarding the provision of systematic nutrition recommendations to pregnant women.
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Affiliation(s)
- Ermioni Tsarna
- 2nd Department of Obstetrics and Gynecology, Aretaieion University Hospital, Athens Medical School, 11527 Athens, Greece
| | - Anna Eleftheriades
- Postgraduate Programme “Maternal Fetal Medicine”, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - Efthymia Tsomi
- 2nd Department of Obstetrics and Gynecology, Aretaieion University Hospital, Athens Medical School, 11527 Athens, Greece
| | - Georgia Ziogou
- 2nd Department of Obstetrics and Gynecology, Aretaieion University Hospital, Athens Medical School, 11527 Athens, Greece
| | - Panagiotis Vakas
- 2nd Department of Obstetrics and Gynecology, Aretaieion University Hospital, Athens Medical School, 11527 Athens, Greece
| | - Theodoros Panoskaltsis
- 2nd Department of Obstetrics and Gynecology, Aretaieion University Hospital, Athens Medical School, 11527 Athens, Greece
| | - Panagiotis Christopoulos
- 2nd Department of Obstetrics and Gynecology, Aretaieion University Hospital, Athens Medical School, 11527 Athens, Greece
- Correspondence:
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Therapeutic Effects of Green Tea Polyphenol (‒)-Epigallocatechin-3-Gallate (EGCG) in Relation to Molecular Pathways Controlling Inflammation, Oxidative Stress, and Apoptosis. Int J Mol Sci 2022; 24:ijms24010340. [PMID: 36613784 PMCID: PMC9820274 DOI: 10.3390/ijms24010340] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/20/2022] [Accepted: 12/22/2022] [Indexed: 12/28/2022] Open
Abstract
(‒)-Epigallocatechin-3-gallate (EGCG) is the most abundant polyphenol in green tea. Thanks to multiple interactions with cell surface receptors, intracellular signaling pathways, and nuclear transcription factors, EGCG possesses a wide variety of anti-inflammatory, antioxidant, antifibrotic, anti-remodelation, and tissue-protective properties which may be useful in the treatment of various diseases, particularly in cancer, and neurological, cardiovascular, respiratory, and metabolic disorders. This article reviews current information on the biological effects of EGCG in the above-mentioned disorders in relation to molecular pathways controlling inflammation, oxidative stress, and cell apoptosis.
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Zhang X, Zhang L, Zhang B, Liu K, Sun J, Li Q, Zhao L. Herbal tea, a novel adjuvant therapy for treating type 2 diabetes mellitus: A review. Front Pharmacol 2022; 13:982387. [PMID: 36249806 PMCID: PMC9561533 DOI: 10.3389/fphar.2022.982387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/30/2022] [Indexed: 11/29/2022] Open
Abstract
Type 2 diabetes mellitus (T2DM) is a metabolic, endocrine disease characterized by persistent hyperglycemia. Several studies have shown that herbal tea improves glucose metabolism disorders in patients with T2DM. This study summarizes the published randomized controlled trials (RCTs) on herbal tea as a adjuvant therapy for treating T2DM and found that herbal teas have potential add-on effects in lowering blood glucose levels. In addition, we discussed the polyphenol contents in common herbal teas and their possible adverse effects. To better guide the application of herbal teas, we further summarized the hypoglycemic mechanisms of common herbal teas, which mainly involve: 1) improving insulin resistance, 2) protecting islet β-cells, 3) anti-inflammation and anti-oxidation, 4) inhibition of glucose absorption, and 5) suppression of gluconeogenesis. In conclusion, herbal tea, as a novel adjuvant therapy for treating T2DM, has the potential for further in-depth research and product development.
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Affiliation(s)
- Xiangyuan Zhang
- Department of Institute of Metabolic Diseases, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- Graduate College, Beijing University of Traditional Chinese Medicine, Beijing, China
| | - Lili Zhang
- Department of Institute of Metabolic Diseases, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Boxun Zhang
- Department of Institute of Metabolic Diseases, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Ke Liu
- Department of Institute of Metabolic Diseases, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Jun Sun
- Graduate College, Changchun University of Traditional Chinese Medicine, Jilin, China
| | - Qingwei Li
- Department of Institute of Metabolic Diseases, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- *Correspondence: Qingwei Li, ; Linhua Zhao,
| | - Linhua Zhao
- Department of Institute of Metabolic Diseases, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- *Correspondence: Qingwei Li, ; Linhua Zhao,
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Identifying Glucose Metabolism Status in Nondiabetic Japanese Adults Using Machine Learning Model with Simple Questionnaire. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2022; 2022:1026121. [PMID: 36118835 PMCID: PMC9481387 DOI: 10.1155/2022/1026121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 08/01/2022] [Accepted: 08/29/2022] [Indexed: 11/17/2022]
Abstract
We aimed to identify the glucose metabolism statuses of nondiabetic Japanese adults using a machine learning model with a questionnaire. In this cross-sectional study, Japanese adults (aged 20–64 years) from Tokyo and surrounding areas were recruited. Participants underwent an oral glucose tolerance test (OGTT) and completed a questionnaire regarding lifestyle and physical characteristics. They were classified into four glycometabolic categories based on the OGTT results: category 1: best glucose metabolism, category 2: low insulin sensitivity, category 3: low insulin secretion, and category 4: combined characteristics of categories 2 and 3. A total of 977 individuals were included; the ratios of participants in categories 1, 2, 3, and 4 were 46%, 21%, 14%, and 19%, respectively. Machine learning models (decision tree, support vector machine, random forest, and XGBoost) were developed for identifying the glycometabolic category using questionnaire responses. Then, the top 10 most important variables in the random forest model were selected, and another random forest model was developed using these variables. Its areas under the receiver operating characteristic curve (AUCs) to classify category 1 and the others, category 2 and the others, category 3 and the others, and category 4 and the others were 0.68 (95% confidence intervals: 0.62–0.75), 0.66 (0.58–0.73), 0.61 (0.51–0.70), and 0.70 (0.62–0.77). For external validation of the model, the same dataset of 452 Japanese adults in Hokkaido was obtained. The AUCs to classify categories 1, 2, 3, and 4 and the others were 0.66 (0.61–0.71), 0.57 (0.51–0.62), 0.60 (0.50–0.69), and 0.64 (0.57–0.71). In conclusion, our model could identify the glucose metabolism status using only 10 factors of lifestyle and physical characteristics. This model may help the larger general population without diabetes to understand their glucose metabolism status and encourage lifestyle improvement to prevent diabetes.
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Zhang Y, Wang R, Tang X, Wang Y, Guo P, Wang S, Liu J. A Mendelian Randomization Study of the Effect of Tea Intake on Type 2 Diabetes. Front Genet 2022; 13:835917. [PMID: 35422845 PMCID: PMC9001914 DOI: 10.3389/fgene.2022.835917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 02/09/2022] [Indexed: 11/13/2022] Open
Abstract
Background: The association reported between tea intake and type 2 diabetes (T2D) is inconsistent in previous studies and remains controversial. We aimed to explore the causal relationship between tea intake, T2D, and glycemic traits including hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), fasting serum insulin (FSI), and homeostasis model of insulin resistance (HOMA-IR) levels. Methods: A 2-sample Mendelian randomization (MR) was performed using summary statistics from large-scale genome-wide association studies of tea intake from the UK Biobank, T2D from the DIAGRAM consortium, and glycemic traits from the Magic consortium. The findings were verified through sensitivity analyses using various MR methods with different model assumptions and by comprehensively evaluating the influence of pleiotropy effects and outliers. Results: With the use of a two-sample MR with inverse variance-weighted method, the odds ratio per unit SD change of tea intake (SD: 2.85 cups/day) for T2D, HbA1c, FPG, FSI, and HOMA-IR levels was 0.949 (95% CI 0.844-1.067, p = 0.383), 0.994 (95% CI 0.975-1.013, p = 0.554), 0.996 (95% CI 0.978-1.015, p = 0.703), 0.968 (95% CI 0.948-0.986, p = 0.001), and 0.953 (95% CI 0.900-1.009, p = 0.102), respectively. The results were consistent with those of the other six methods that we used with different model assumptions, suggesting that the findings were robust and convincing. We also performed various sensitivity analyses for outlier removal, pleiotropy detection, and leave-one-out analysis. Conclusion: Our MR results did not support the causal effect of tea intake on T2D and crucial glycemic traits. These findings suggest that previous observational studies may have been confounded.
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Affiliation(s)
- Yanan Zhang
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Ruiqing Wang
- Department of Hematology, Qilu Hospital of Shandong University, Jinan, China
| | - Xinhua Tang
- School of Cyberspace Security, Shandong University of Political Science and Law, Jinan, China
| | - Yanjun Wang
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Ping Guo
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Shukang Wang
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Jing Liu
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China
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Liu F, Sirisena S, Ng K. Efficacy of flavonoids on biomarkers of type 2 diabetes mellitus: a systematic review and meta-analysis of randomized controlled trials. Crit Rev Food Sci Nutr 2021:1-27. [PMID: 34842001 DOI: 10.1080/10408398.2021.2009761] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
A systematic review and meta-analysis of 28 randomized controlled trials (RCTs) to assess the efficacy of flavonoids intake on key biomarkers related to Type 2 diabetes mellitus was conducted. The mean difference (MD) with 95% confidence intervals (95% CI) was pooled using a random-effects model. Significant reduction in fasting glucose (MD: -0.22, 95% CI: -0.34 to -0.09, p = 0.0013), hemoglobin A1c (HbA1c) (MD: -0.26, 95% CI: -0.46 to -0.05, p = 0.021), homeostasis model assessment of insulin resistance (HOMA-IR) (MD: -0.40, 95% CI: -0.66 to -0.15, p = 0.0039), triglyceride (TG) (MD: -0.13, 95% CI: -0.21 to -0.05, p = 0.002), total cholesterol (TC) (MD: -0.14, 95% CI: -0.21 to -0.08, p = 0.0002), and low density lipoprotein-C (LDL-C) (MD: -0.15; 95% CI: -0.24 to -0.07, p = 0.0009) were observed in intervention group compare to placebo at the end of trial. Moreover, flavonoid intake had negative but non-significant effect on insulin (MD: -0.46), 2 h-postprandial glucose (2 h-PPG) (MD: -0.22), homeostasis model assessment of β-cell function (HOMA-β) (MD: -2.81), and insignificantly increased high-density lipoprotein-C (HDL-C) (MD: 0.03). In conclusion, flavonoid intake has modest but statistically significant benefits in glucose metabolism, insulin sensitivity, and lipid metabolism, especially for significantly lowing fasting blood glucose, HOMA-IR, HbA1c, TG, TC, and LDL-C.
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Affiliation(s)
- Fanling Liu
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Sameera Sirisena
- Department of Chemical Engineering, Faculty of Engineering and Information Technology, The University of Melbourne, Parkville, VIC, Australia
| | - Ken Ng
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia
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He M, Lyu X. Application of BRAFO-tiered approach for health benefit-risk assessment of dark tea consumption in China. Food Chem Toxicol 2021; 158:112615. [PMID: 34656696 DOI: 10.1016/j.fct.2021.112615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 09/09/2021] [Accepted: 10/12/2021] [Indexed: 11/17/2022]
Abstract
Dark tea, a unique tea fermented primarily in China, has numerous potential beneficial effects. However, harmful substances present in dark tea have provoked significant concern. To conduct a quantitative benefit-risk assessment of dark tea for Chinese residents and provide guidance on rational consumption, a framework of Benefit-Risk Analysis for Foods (BRAFO) and meta-analysis was applied to construct a disability-adjusted life year (DALY). Based on the BRAFO-tiered approach, a reference scenario (no intake) and an alternative scenario (intake of 3 cups/day) were determined. The overall health impacts of dark tea were simulated by comparing the risks of fluoride and AF with benefits of reduced-risk to coronary heart disease (CHD) and diabetes in different scenarios. Three cups of fermented tea consumed per day decreased risks of CHD and diabetes by 8.16% and 12.77% respectively. After quantitative integration of information, the ultimate net health effect was found to be -1958.827 illustrating that the benefits of drinking three cups of dark tea per day outweigh the risks. However, considering the uncertainties in the process, decision-makers should proceed with caution, consulting additional well-conducted studies and further managing harmful substances in dark tea.
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Affiliation(s)
- Mengru He
- Department of Nutrition and Food Hygiene, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, 610041, China
| | - Xiaohua Lyu
- Department of Nutrition and Food Hygiene, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, 610041, China.
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Nie J, Yu C, Guo Y, Pei P, Chen L, Pang Y, Du H, Yang L, Chen Y, Yan S, Chen J, Chen Z, Lv J, Li L. Tea consumption and long-term risk of type 2 diabetes and diabetic complications: a cohort study of 0.5 million Chinese adults. Am J Clin Nutr 2021; 114:194-202. [PMID: 33709113 PMCID: PMC8246622 DOI: 10.1093/ajcn/nqab006] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 01/04/2021] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Evidence from epidemiological studies remains inconsistent or limited about the associations of tea consumption with incident diabetes and risk of diabetic complications and death among patients with diabetes. OBJECTIVES We aimed to investigate the associations of tea consumption with long-term risk of developing type 2 diabetes (T2D) and risks of diabetic complications and death among patients with diabetes. METHODS This study included 482,425 diabetes-free participants and 30,300 patients with diabetes aged 30-79 y at study enrollment from the China Kadoorie Biobank. Tea consumption information was collected at baseline by interviewer-administered questionnaires. Incidences of diabetes, diabetic complications, and death were identified by linkages to the National Health Insurance system, disease registries, and death registries. Cox proportional hazard regression models were used to estimate HRs and 95% CIs. RESULTS The mean ± SD age of participants free of diabetes was 51.2 ± 10.5 y and 41% were male. The mean ± SD age of patients with diabetes was 58.2 ± 9.6 y and 39% were male. Of all daily tea consumers, 85.8% preferred green tea. In the diabetes-free population, 17,434 participants developed incident T2D during 11.1 y of follow-up. Compared with participants who never consumed tea in the past year, the HR (95% CI) of T2D for daily consumers was 0.92 (0.88, 0.97). In patients with diabetes, we identified 6572 deaths, 12,677 diabetic macrovascular cases, and 2441 diabetic microvascular cases during follow-up. Compared with patients who never consumed tea in the past year, the HRs (95% CIs) of all-cause mortality and risk of microvascular complications for daily consumers were 0.90 (0.83, 0.97) and 0.88 (0.78, 1.00), respectively. Tea consumption was not associated with risk of macrovascular complications among patients with diabetes. With regard to tea consumed, the inverse associations between daily tea consumption and risks of T2D and all-cause mortality in patients with diabetes were only observed among daily green tea drinkers. CONCLUSIONS In Chinese adults, daily green tea consumption was associated with a lower risk of incident T2D and a lower risk of all-cause mortality in patients with diabetes, but the associations for other types of tea were less clear. In addition, daily tea consumption was associated with a lower risk of diabetic microvascular complications, but not macrovascular complications.
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Affiliation(s)
- Jia Nie
- Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China
| | - Canqing Yu
- Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China
- Peking University Center for Public Health and Epidemic Preparedness and Response, Beijing, China
| | - Yu Guo
- Chinese Academy of Medical Sciences, Beijing, China
| | - Pei Pei
- Chinese Academy of Medical Sciences, Beijing, China
| | - Lu Chen
- Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China
| | - Yuanjie Pang
- Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China
- Peking University Center for Public Health and Epidemic Preparedness and Response, Beijing, China
| | - Huaidong Du
- Medical Research Council Population Health Research Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
- Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | - Ling Yang
- Medical Research Council Population Health Research Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
- Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | - Yiping Chen
- Medical Research Council Population Health Research Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
- Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | - Shichun Yan
- NCDs Prevention and Control Department, Heilongjiang CDC, Heilongjiang, China
| | - Junshi Chen
- China National Center for Food Safety Risk Assessment, Beijing, China
| | - Zhengming Chen
- Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | - Jun Lv
- Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China
- Peking University Center for Public Health and Epidemic Preparedness and Response, Beijing, China
- Key Laboratory of Molecular Cardiovascular Sciences (Peking University), Ministry of Education, Beijing, China
| | - Liming Li
- Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China
- Peking University Center for Public Health and Epidemic Preparedness and Response, Beijing, China
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12
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Shadyab AH, Manson JE, Luo J, Haring B, Saquib N, Snetselaar LG, Chen JC, Groessl EJ, Wassertheil-Smoller S, Sun Y, Hale L, LeBoff MS, LaCroix AZ. Associations of Coffee and Tea Consumption With Survival to Age 90 Years Among Older Women. J Am Geriatr Soc 2020; 68:1970-1978. [PMID: 32329900 PMCID: PMC8580285 DOI: 10.1111/jgs.16467] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 03/21/2020] [Accepted: 03/23/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Coffee and tea are two of the most widely consumed beverages worldwide and have been associated with reduced risk of mortality in some studies. However, it is unknown whether consumption of these beverages is associated with survival to an advanced age. OBJECTIVE To examine associations of coffee and tea consumption with survival to age 90 years. DESIGN Prospective cohort study among participants from the Women's Health Initiative, recruited during 1993 to 1998 and followed up until March 31, 2018. SETTING The setting included 40 US clinical centers. PARTICIPANTS A racially and ethnically diverse cohort of 27,480 older women, aged 65 to 81 years at baseline. MEASUREMENTS Women were classified as having either survived to age 90 years or died before this age. Consumption of caffeinated and decaffeinated coffee and caffeinated tea was assessed at baseline and categorized as 0, 1, 2 to 3, or 4 or more cups/day. Associations of coffee and tea consumption with survival to age 90 years were examined using logistic regression models adjusted for sociodemographic characteristics, lifestyle behaviors, dietary quality, and chronic disease history. RESULTS A total of 14,659 (53.3%) women survived to age 90 years during follow-up. Caffeinated coffee, decaffeinated coffee, or caffeinated tea consumption was not significantly associated with survival to age 90 years after adjusting for confounders. Findings did not significantly vary by smoking, body mass index, or race/ethnicity. CONCLUSION No amount of coffee or tea consumption was associated with late-age survival among older women. These findings may be reassuring to older women who consume coffee and tea as part of their daily diets but do not support drinking these beverages to achieve longevity.
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Affiliation(s)
- Aladdin H. Shadyab
- Department of Family Medicine and Public Health, University of California, San Diego School of Medicine, La Jolla, CA
| | - JoAnn E. Manson
- Department of Epidemiology, Harvard T.H. Chan School of Public Health and Division of Preventive Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA
| | - Juhua Luo
- Department of Epidemiology and Biostatistics, School of Public Health, Indiana University, Bloomington, IN
| | - Bernhard Haring
- Department of Internal Medicine I, University of Würzburg, Würzburg, Germany
| | - Nazmus Saquib
- College of Medicine, Sulaiman AlRajhi University, Al Bukayriyah, Saudi Arabia
| | - Linda G. Snetselaar
- Department of Epidemiology, College of Public Health, University of Iowa, Iowa City, IA
| | - Jiu-Chiuan Chen
- Departments of Preventive Medicine and Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Erik J. Groessl
- Department of Family Medicine and Public Health, University of California, San Diego School of Medicine, La Jolla, CA
| | | | - Yangbo Sun
- Department of Epidemiology, College of Public Health, University of Iowa, Iowa City, IA
| | - Lauren Hale
- Department of Family, Population and Preventive Medicine, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY
| | - Meryl S. LeBoff
- Division of Endocrinology, Diabetes, and Hypertension, Department of Medicine, Brigham and Woman's Hospital, Harvard Medical School, Boston, MA
| | - Andrea Z. LaCroix
- Department of Family Medicine and Public Health, University of California, San Diego School of Medicine, La Jolla, CA
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The Intrinsic Virtues of EGCG, an Extremely Good Cell Guardian, on Prevention and Treatment of Diabesity Complications. Molecules 2020; 25:molecules25133061. [PMID: 32635492 PMCID: PMC7411588 DOI: 10.3390/molecules25133061] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/01/2020] [Accepted: 07/02/2020] [Indexed: 12/19/2022] Open
Abstract
The pandemic proportion of diabesity—a combination of obesity and diabetes—sets a worldwide health issue. Experimental and clinical studies have progressively reinforced the pioneering epidemiological observation of an inverse relationship between consumption of polyphenol-rich nutraceutical agents and mortality from cardiovascular and metabolic diseases. With chemical identification of epigallocatechin-3-gallate (EGCG) as the most abundant catechin of green tea, a number of cellular and molecular mechanisms underlying the activities of this unique catechin have been proposed. Favorable effects of EGCG have been initially attributed to its scavenging effects on free radicals, inhibition of ROS-generating mechanisms and upregulation of antioxidant enzymes. Biologic actions of EGCG are concentration-dependent and under certain conditions EGCG may exert pro-oxidant activities, including generation of free radicals. The discovery of 67-kDa laminin as potential EGCG membrane target has broaden the likelihood that EGCG may function not only because of its highly reactive nature, but also via receptor-mediated activation of multiple signaling pathways involved in cell proliferation, angiogenesis and apoptosis. Finally, by acting as epigenetic modulator of DNA methylation and chromatin remodeling, EGCG may alter gene expression and modify miRNA activities. Despite unceasing research providing detailed insights, ECGC composite activities are still not completely understood. This review summarizes the most recent evidence on molecular mechanisms by which EGCG may activate signal transduction pathways, regulate transcription factors or promote epigenetic changes that may contribute to prevent pathologic processes involved in diabesity and its cardiovascular complications.
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14
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Márquez Campos E, Jakobs L, Simon MC. Antidiabetic Effects of Flavan-3-ols and Their Microbial Metabolites. Nutrients 2020; 12:nu12061592. [PMID: 32485837 PMCID: PMC7352288 DOI: 10.3390/nu12061592] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 05/17/2020] [Accepted: 05/26/2020] [Indexed: 12/11/2022] Open
Abstract
Diet is one of the pillars in the prevention and management of diabetes mellitus. Particularly, eating patterns characterized by a high consumption of foods such as fruits or vegetables and beverages such as coffee and tea could influence the development and progression of type 2 diabetes. Flavonoids, whose intake has been inversely associated with numerous negative health outcomes in the last few years, are a common constituent of these food items. Therefore, they could contribute to the observed positive effects of certain dietary habits in individuals with type 2 diabetes. Of all the different flavonoid subclasses, flavan-3-ols are consumed the most in the European region. However, a large proportion of the ingested flavan-3-ols is not absorbed. Therefore, the flavan-3-ols enter the large intestine where they become available to the colonic bacteria and are metabolized by the microbiota. For this reason, in addition to the parent compounds, the colonic metabolites of flavan-3-ols could take part in the prevention and management of diabetes. The aim of this review is to present the available literature on the effect of both the parent flavan-3-ol compounds found in different food sources as well as the specific microbial metabolites of diabetes in order to better understand their potential role in the prevention and treatment of the disease.
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15
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Consuming decaffeinated coffee with milk and sugar added before a high-glycaemic index meal improves postprandial glycaemic and insulinaemic responses in healthy adults. Br J Nutr 2020; 124:785-796. [PMID: 32418547 DOI: 10.1017/s0007114520001750] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The present study aimed to compare the effects of drinking different types of coffee before a high-glycaemic index (GI) meal on postprandial glucose metabolism and to assess the effects of adding milk and sugar into coffee. In this randomised, crossover, acute feeding study, apparently healthy adults (n 21) consumed the test drink followed by a high-GI meal in each session. Different types of coffee (espresso, instant, boiled and decaffeinated, all with milk and sugar) and plain water were tested in separate sessions, while a subset of the participants (n 10) completed extra sessions using black coffees. Postprandial levels of glucose, insulin, active glucagon-like peptide 1 (GLP-1) and nitrotyrosine between different test drinks were compared using linear mixed models. Results showed that only preloading decaffeinated coffee with milk and sugar led to significantly lower glucose incremental AUC (iAUC; 14 % lower, P = 0·001) than water. Preloading black coffees led to greater postprandial glucose iAUC than preloading coffees with milk and sugar added (12-35 % smaller, P < 0·05 for all coffee types). Active GLP-1 and nitrotyrosine levels were not significantly different between test drinks. To conclude, preloading decaffeinated coffee with milk and sugar led to a blunted postprandial glycaemic response after a subsequent high-GI meal, while adding milk and sugar into coffee could mitigate the impairment effect of black coffee towards postprandial glucose responses. These findings may partly explain the positive effects of coffee consumption on glucose metabolism.
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16
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Imamura F, Schulze MB, Sharp SJ, Guevara M, Romaguera D, Bendinelli B, Salamanca-Fernández E, Ardanaz E, Arriola L, Aune D, Boeing H, Dow C, Fagherazzi G, Franks PW, Freisling H, Jakszyn P, Kaaks R, Khaw KT, Kühn T, Mancini FR, Masala G, Chirlaque MD, Nilsson PM, Overvad K, Pala VM, Panico S, Perez-Cornago A, Quirós JR, Ricceri F, Rodríguez-Barranco M, Rolandsson O, Sluijs I, Stepien M, Spijkerman AMW, Tjønneland A, Tong TYN, Tumino R, Vissers LET, Ward HA, Langenberg C, Riboli E, Forouhi NG, Wareham NJ. Estimated Substitution of Tea or Coffee for Sugar-Sweetened Beverages Was Associated with Lower Type 2 Diabetes Incidence in Case-Cohort Analysis across 8 European Countries in the EPIC-InterAct Study. J Nutr 2019; 149:1985-1993. [PMID: 31396627 PMCID: PMC6825826 DOI: 10.1093/jn/nxz156] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 04/01/2019] [Accepted: 06/11/2019] [Indexed: 12/31/2022] Open
Abstract
INTRODUCTION Beverage consumption is a modifiable risk factor for type 2 diabetes (T2D), but there is insufficient evidence to inform the suitability of substituting 1 type of beverage for another. OBJECTIVE The aim of this study was to estimate the risk of T2D when consumption of sugar-sweetened beverages (SSBs) was replaced with consumption of fruit juice, milk, coffee, or tea. METHODS In the European Prospective Investigation into Cancer and Nutrition (EPIC)-InterAct case-cohort study of 8 European countries (n = 27,662, with 12,333 cases of incident T2D, 1992-2007), beverage consumption was estimated at baseline by dietary questionnaires. Using Prentice-weighted Cox regression adjusting for other beverages and potential confounders, we estimated associations of substituting 1 type of beverage for another on incident T2D. RESULTS Mean ± SD of estimated consumption of SSB was 55 ± 105 g/d. Means ± SDs for the other beverages were as follows: fruit juice, 59 ± 101 g/d; milk, 209 ± 203 g/d; coffee, 381 ± 372 g/d; and tea, 152 ± 282 g/d. Substituting coffee for SSBs by 250 g/d was associated with a 21% lower incidence of T2D (95% CI: 12%, 29%). The rate difference was -12.0 (95% CI: -20.0, -5.0) per 10,000 person-years among adults consuming SSBs ≥250 g/d (absolute rate = 48.3/10,000). Substituting tea for SSBs was estimated to lower T2D incidence by 22% (95% CI: 15%, 28%) or -11.0 (95% CI: -20.0, -2.6) per 10,000 person-years, whereas substituting fruit juice or milk was estimated not to alter T2D risk significantly. CONCLUSIONS These findings indicate a potential benefit of substituting coffee or tea for SSBs for the primary prevention of T2D and may help formulate public health recommendations on beverage consumption in different populations.
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Affiliation(s)
- Fumiaki Imamura
- Medical Research Council Epidemiology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Matthias B Schulze
- Department of Molecular Epidemiology, Germen Institute of Human Nutrition, Potsdam, Germany
| | - Stephen J Sharp
- Medical Research Council Epidemiology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Marcela Guevara
- IDISNA Navarra Health Research Institute, Pamplona, Spain
- CIBER Epidemiology and Public Health, Madrid, Spain
| | - Dora Romaguera
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
- Health Research Institute of Balearic Islands (IdISBa), Palma de Mallorca, Spain
- CIBER Physiopathology of Obesity and Nutrition, Madrid, Spain
| | - Benedetta Bendinelli
- Cancer Risk Factors and Lifestyle Epidemiology Unit, Institute for Cancer Research, Prevention and Clinical Network (ISPRO), Florence, Italy
| | - Elena Salamanca-Fernández
- CIBER Epidemiology and Public Health, Madrid, Spain
- Andalusian School of Public Health, Institute of Investigation Instituto de Investigación Biosanitaria de Granada (ibs.GRANADA), University of Granada, Granada, Spain
| | - Eva Ardanaz
- IDISNA Navarra Health Research Institute, Pamplona, Spain
- CIBER Epidemiology and Public Health, Madrid, Spain
| | - Larraitz Arriola
- Public Health Division of Gipuzkoa, Instituto BIO-Donostia, Basque Government, CIBERESP, Gipuzkoa, Spain
| | - Dagfinn Aune
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
- Department of Nutrition, Bjørknes University College, Oslo, Norway
- Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital Ullevål, Oslo, Norway
| | - Heiner Boeing
- Department of Molecular Epidemiology, Germen Institute of Human Nutrition, Potsdam, Germany
| | - Courtney Dow
- Gustave Roussy Institute, Villejuif, France
- University Paris–South, Faculty of Medicine, University Versailles–St Quentin, University Paris-Saclay, Villejuif, France
- National Institute for Health and Medical Research (INSERM), Center for Research in Epidemiology and Population Health, Villejuif, France
| | - Guy Fagherazzi
- Gustave Roussy Institute, Villejuif, France
- University Paris–South, Faculty of Medicine, University Versailles–St Quentin, University Paris-Saclay, Villejuif, France
- National Institute for Health and Medical Research (INSERM), Center for Research in Epidemiology and Population Health, Villejuif, France
| | - Paul W Franks
- Department of Public Health and Clinical Medicine, Family Medicine, Umeå University, Umeå, Sweden
- Department of Clinical Sciences, Lund University, Skane University Hospital, Malmo, Sweden
| | - Heinz Freisling
- Section of Nutrition and Metabolism, International Agency for Research on Cancer (IARC–WHO), Lyon, France
| | - Paula Jakszyn
- Catalan Institute of Oncology, Barcelona, Spain
- FCS Blanquerna, Universitat Ramon Llull, Barcelona, Spain
| | - Rudolf Kaaks
- Division of Cancer Epidemiology, German Cancer Research Center, Heidelberg, Germany
| | - Kay-Tee Khaw
- Department of Public Health and Primary Care, University of Cambridge School of Clinical Medicine, Cambridge, United Kingdom
| | - Tilman Kühn
- Division of Cancer Epidemiology, German Cancer Research Center, Heidelberg, Germany
| | - Francesca R Mancini
- Gustave Roussy Institute, Villejuif, France
- University Paris–South, Faculty of Medicine, University Versailles–St Quentin, University Paris-Saclay, Villejuif, France
- National Institute for Health and Medical Research (INSERM), Center for Research in Epidemiology and Population Health, Villejuif, France
| | - Giovanna Masala
- Cancer Risk Factors and Lifestyle Epidemiology Unit, Institute for Cancer Research, Prevention and Clinical Network (ISPRO), Florence, Italy
| | - Maria-Dolores Chirlaque
- CIBER Epidemiology and Public Health, Madrid, Spain
- Department of Epidemiology, Regional Health Council, IMIB-Arrixaca, Murcia, Spain
- Department of Health and Social Sciences, Universidad de Murcia, Murcia, Spain
| | - Peter M Nilsson
- Department of Clinical Sciences, Lund University, Skane University Hospital, Malmo, Sweden
| | - Kim Overvad
- Department of Cardiology, Aalborg University Hospital, Aarhus, Denmark
- Section for Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Valeria M Pala
- Epidemiology and Prevention Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Salvatore Panico
- Dipartimento di Medicina Clinica e Chirurgia, Federico II University, Naples, Italy
| | - Aurora Perez-Cornago
- Cancer Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | | | - Fulvio Ricceri
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
- Unit of Epidemiology, Regional Health Service ASL TO3, Grugliasco, Italy
| | - Miguel Rodríguez-Barranco
- CIBER Epidemiology and Public Health, Madrid, Spain
- Andalusian School of Public Health, Institute of Investigation Instituto de Investigación Biosanitaria de Granada (ibs.GRANADA), University of Granada, Granada, Spain
| | - Olov Rolandsson
- Department of Public Health and Clinical Medicine, Family Medicine, Umeå University, Umeå, Sweden
| | - Ivonne Sluijs
- Julius Center for Health Sciences and Primary Care, Cardiovascular Epidemiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Magdalena Stepien
- Section of Nutrition and Metabolism, International Agency for Research on Cancer (IARC–WHO), Lyon, France
| | | | | | - Tammy Y N Tong
- Cancer Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | - Rosario Tumino
- Cancer Registry and Histopathology Department, “Civic-M.P. Arezzo” Hospital, Ragusa, Italy
| | - Linda E T Vissers
- Julius Center for Health Sciences and Primary Care, Cardiovascular Epidemiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Heather A Ward
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
| | - Claudia Langenberg
- Medical Research Council Epidemiology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Elio Riboli
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
| | - Nita G Forouhi
- Medical Research Council Epidemiology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Nick J Wareham
- Medical Research Council Epidemiology Unit, University of Cambridge, Cambridge, United Kingdom
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Zhang L, Ho CT, Zhou J, Santos JS, Armstrong L, Granato D. Chemistry and Biological Activities of Processed Camellia sinensis Teas: A Comprehensive Review. Compr Rev Food Sci Food Saf 2019; 18:1474-1495. [PMID: 33336903 DOI: 10.1111/1541-4337.12479] [Citation(s) in RCA: 247] [Impact Index Per Article: 49.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 06/05/2019] [Accepted: 06/25/2019] [Indexed: 01/20/2023]
Abstract
Tea is a typical processed beverage from the fresh leaves of Camellia sinensis [Camellia sinensis (L.) O. Kuntze] or Camellia assamica [Camellia sinensis var. assamica (Mast.) Kitamura] through different manufacturing techniques. The secondary metabolites of fresh tea leaves are mainly flavan-3-ols, phenolic acids, purine alkaloids, condensed tannins, hydrolysable tannins, saponins, flavonols, and their glycoside forms. During the processing, tea leaves go through several steps, such as withering, rolling, fermentation, postfermentation, and roasting (drying) to produce different types of tea. After processing, theaflavins, thearubigins, and flavan-3-ols derivatives emerge as the newly formed compounds with a corresponding decrease in concentrations of catechins. Each type of tea has its own critical process and presents unique chemical composition and flavor. The components among different teas also cause significant changes in their biological activities both in vitro and in vivo. In the present review, the progress of tea chemistry and the effects of individual unit operation on components were comprehensively described. The health benefits of tea were also reviewed based on the human epidemiological and clinical studies. Although there have been multiple studies about the tea chemistry and biological activities, most of existing results are related to tea polyphenols, especially (-)-epigallocatechin gallate. Other compounds, including the novel compounds, as well as isomers of amino acids and catechins, have not been explored in depth.
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Affiliation(s)
- Liang Zhang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural Univ., 230036, Hefei, People's Republic of China
| | - Chi-Tang Ho
- Dept. of Food Science, Rutgers Univ., New Brunswick, 08901-8554, NJ, U.S.A
| | - Jie Zhou
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural Univ., 230036, Hefei, People's Republic of China
| | - Jânio Sousa Santos
- Graduation Program in Food Science and Technology, State Univ. of Ponta Grossa, 84030-900, Ponta Grossa, Brazil
| | - Lorene Armstrong
- Graduation Program in Chemistry, State Univ. of Ponta Grossa, 84030-900, Ponta Grossa, Brazil
| | - Daniel Granato
- Graduation Program in Food Science and Technology, State Univ. of Ponta Grossa, 84030-900, Ponta Grossa, Brazil.,Innovative Food System Unit, Natural Resources Inst. Finland (LUKE), FI-02150, Espoo, Finland
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18
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Zielinski AA, Haminiuk CW, Beta T. Evaluation of the Phenolics and in vitro Antioxidant Activity of Different Botanical Herbals Used for Tea Infusions in Brazil. CURRENT NUTRITION & FOOD SCIENCE 2019. [DOI: 10.2174/1573401313666171020114727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:
The consumption of herbal teas has gained much attention due to its healthpromoting
benefits, including antioxidant, neuroprotective, antimicrobial, antitumor, and antiinflammatory
effects. These biological activities are associated in part to the antioxidant activity of
chemical compounds present in teas, especially flavonoids and phenolic acids.
Objective:
The aim of this study was to evaluate a total of 17 different botanical herbal infusions consumed
in Brazil in terms of their phenolic antioxidants.
Methods:
The analysis performed were total phenolic compounds, total flavonoids, total flavonols,
tannin content and in vitro antioxidant activity (DPPH, ABTS, CUPRAC, FRAP, and ORAC assays).
Data were processed using univariate, bivariate and multivariate analysis (hierarchical cluster analysis).
Results:
The use of Hierarchical Cluster Analysis (HCA) suggested an unsupervised classification relationship
based on level of functionality of the herbal teas. Higher levels of total phenolics, total flavonoids
and antioxidant activity were found in Anemopaegma mirandum while higher values of tannin
content and total flavonols were found in Peumus boldus. All antioxidant activity assays showed significant
correlations among each other (r > 0.84, p < 0.001), and with total phenolic and flavonoids (r
> 0.83, p < 0.001). Using HCA, three clusters were suggested and cluster 1 showed the highest functionality.
Conclusion:
The herbal infusions evaluated can be a good resource of bioactive compounds to consume
and supplementing food products. Nevertheless, future studies should focus on the evaluation of
these herbal teas using in vivo systems to understand the mechanisms of action when these different
herbal infusions are used as beverages.
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Affiliation(s)
- Acácio A.F. Zielinski
- Department of Chemical Engineering and Food Engineering - Federal University of Santa Catarina (UFSC), Florianopolis, SC, 88010-970, Brazil
| | - Charles W.I. Haminiuk
- Graduate Programme of Food Technology, Federal University of Technology, Paraná, via Rosalina Maria dos Santos 1233 Campo Mourao Campus, CEP 87301-899 Campo Mourao, Brazil
| | - Trust Beta
- University of Manitoba, Department of Food & Human Nutritional Sciences, 250 Ellis Building, Winnipeg, Manitoba R3T 2N2, Canada
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19
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Meng JM, Cao SY, Wei XL, Gan RY, Wang YF, Cai SX, Xu XY, Zhang PZ, Li HB. Effects and Mechanisms of Tea for the Prevention and Management of Diabetes Mellitus and Diabetic Complications: An Updated Review. Antioxidants (Basel) 2019; 8:E170. [PMID: 31185622 PMCID: PMC6617012 DOI: 10.3390/antiox8060170] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/04/2019] [Accepted: 06/06/2019] [Indexed: 02/07/2023] Open
Abstract
Diabetes mellitus has become a serious and growing public health concern. It has high morbidity and mortality because of its complications, such as diabetic nephropathy, diabetic cardiovascular complication, diabetic neuropathy, diabetic retinopathy, and diabetic hepatopathy. Epidemiological studies revealed that the consumption of tea was inversely associated with the risk of diabetes mellitus and its complications. Experimental studies demonstrated that tea had protective effects against diabetes mellitus and its complications via several possible mechanisms, including enhancing insulin action, ameliorating insulin resistance, activating insulin signaling pathway, protecting islet β-cells, scavenging free radicals, and decreasing inflammation. Moreover, clinical trials also confirmed that tea intervention is effective in patients with diabetes mellitus and its complications. Therefore, in order to highlight the importance of tea in the prevention and management of diabetes mellitus and its complications, this article summarizes and discusses the effects of tea against diabetes mellitus and its complications based on the findings from epidemiological, experimental, and clinical studies, with the special attention paid to the mechanisms of action.
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Affiliation(s)
- Jin-Ming Meng
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China.
| | - Shi-Yu Cao
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China.
| | - Xin-Lin Wei
- Department of Food Science & Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Ren-You Gan
- Department of Food Science & Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Yuan-Feng Wang
- College of Life Sciences, Shanghai Normal University, 100 Guilin Road, Shanghai 200234, China.
| | - Shu-Xian Cai
- Key Laboratory of Ministry of Education for Tea Science, Hunan Agricultural University, Changsha 410128, China.
| | - Xiao-Yu Xu
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China.
| | - Pang-Zhen Zhang
- School of Agriculture and Food, The University of Melbourne, Parkville, Victoria 3010, Australia.
| | - Hua-Bin Li
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China.
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Jannasch F, Kröger J, Agnoli C, Barricarte A, Boeing H, Cayssials V, Colorado-Yohar S, Dahm CC, Dow C, Fagherazzi G, Franks PW, Freisling H, Gunter MJ, Kerrison ND, Key TJ, Khaw KT, Kühn T, Kyro C, Mancini FR, Mokoroa O, Nilsson P, Overvad K, Palli D, Panico S, García JRQ, Rolandsson O, Sacerdote C, Sánchez MJ, Sahrai MS, Schübel R, Sluijs I, Spijkerman AMW, Tjonneland A, Tong TYN, Tumino R, Riboli E, Langenberg C, Sharp SJ, Forouhi NG, Schulze MB, Wareham NJ. Generalizability of a Diabetes-Associated Country-Specific Exploratory Dietary Pattern Is Feasible Across European Populations. J Nutr 2019; 149:1047-1055. [PMID: 31149710 PMCID: PMC6543295 DOI: 10.1093/jn/nxz031] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 01/02/2019] [Accepted: 02/06/2019] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Population-specificity of exploratory dietary patterns limits their generalizability in investigations with type 2 diabetes incidence. OBJECTIVE The aim of this study was to derive country-specific exploratory dietary patterns, investigate their association with type 2 diabetes incidence, and replicate diabetes-associated dietary patterns in other countries. METHODS Dietary intake data were used, assessed by country-specific questionnaires at baseline of 11,183 incident diabetes cases and 14,694 subcohort members (mean age 52.9 y) from 8 countries, nested within the European Prospective Investigation into Cancer and Nutrition study (mean follow-up time 6.9 y). Exploratory dietary patterns were derived by principal component analysis. HRs for incident type 2 diabetes were calculated by Prentice-weighted Cox proportional hazard regression models. Diabetes-associated dietary patterns were simplified or replicated to be applicable in other countries. A meta-analysis across all countries evaluated the generalizability of the diabetes-association. RESULTS Two dietary patterns per country/UK-center, of which overall 3 dietary patterns were diabetes-associated, were identified. A risk-lowering French dietary pattern was not confirmed across other countries: pooled HRFrance per 1 SD: 1.00; 95% CI: 0.90, 1.10. Risk-increasing dietary patterns, derived in Spain and UK-Norfolk, were confirmed, but only the latter statistically significantly: HRSpain: 1.09; 95% CI: 0.97, 1.22 and HRUK-Norfolk: 1.12; 95% CI: 1.04, 1.20. Respectively, this dietary pattern was characterized by relatively high intakes of potatoes, processed meat, vegetable oils, sugar, cake and cookies, and tea. CONCLUSIONS Only few country/center-specific dietary patterns (3 of 18) were statistically significantly associated with diabetes incidence in this multicountry European study population. One pattern, whose association with diabetes was confirmed across other countries, showed overlaps in the food groups potatoes and processed meat with identified diabetes-associated dietary patterns from other studies. The study demonstrates that replication of associations of exploratory patterns with health outcomes is feasible and a necessary step to overcome population-specificity in associations from such analyses.
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Affiliation(s)
- Franziska Jannasch
- Department of Molecular Epidemiology, German Institute of Human Nutrition Potsdam-Rehbruecke, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
- NutriAct–Competence Cluster Nutrition Research Berlin-Potsdam, Nuthetal, Germany
| | - Janine Kröger
- Department of Molecular Epidemiology, German Institute of Human Nutrition Potsdam-Rehbruecke, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Claudia Agnoli
- Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Aurelio Barricarte
- CIBER de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Navarra Public Health Institute, Pamplona, Spain
- IdiSNA, Navarra Institute for Health Research, Pamplona, Spain
| | - Heiner Boeing
- Department of Epidemiology, German Institute of Human Nutrition Potsdam-Rehbruecke, Nuthetal, Germany
| | - Valerie Cayssials
- Unit of Nutrition and Cancer, Cancer Epidemiology Research Program, Catalan Institute of Oncology, Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain
| | - Sandra Colorado-Yohar
- CIBER de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Department of Epidemiology, Murcia Health Council, IMIB-Arrixaca, Spain
- Research Group on Demography and Health, National Faculty of Public Health, University of Antioquia, Medellín, Colombia
| | - Christina C Dahm
- Section for Epidemiology, Department of Public Health, Aarhus University, Denmark
| | - Courtney Dow
- Inserm, Centre for Research in Epidemiology and Population Health [CESP], Villejuif, France; Université Paris-Sud, Villejuif, France
| | - Guy Fagherazzi
- Inserm, Centre for Research in Epidemiology and Population Health [CESP], Villejuif, France; Université Paris-Sud, Villejuif, France
| | - Paul W Franks
- Department of Clinical Sciences, Lund University, Malmö, Sweden
- Department of Public Health and Clinical Medicine, Umeå University, Sweden
| | - Heinz Freisling
- Section of Nutrition and Metabolism, International Agency for Research on Cancer (IARC-WHO), Lyon, France
| | - Marc J Gunter
- Section of Nutrition and Metabolism, International Agency for Research on Cancer (IARC-WHO), Lyon, France
| | | | - Timothy J Key
- Cancer Epidemiology Unit, University of Oxford, Oxford, United Kingdom
| | - Kay-Tee Khaw
- Department of Public Health and Primary Care, University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom
| | - Tilman Kühn
- German Cancer Research Center [DKFZ], Heidelberg, Germany
| | - Cecilie Kyro
- Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Francesca Romana Mancini
- Inserm, Centre for Research in Epidemiology and Population Health [CESP], Villejuif, France; Université Paris-Sud, Villejuif, France
| | - Olatz Mokoroa
- CIBER de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Public Health Division of Gipuzkoa, Biodonostia Research Institute, San Sebastian, Spain
| | - Peter Nilsson
- Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Kim Overvad
- Section for Epidemiology, Department of Public Health, Aarhus University, Denmark
- Department of Cardiology, Center for Cardiovascular Research, Aalborg Hospital, Aarhus University Hospital, Aalborg, Denmark
| | - Domenico Palli
- Cancer Risk Factors and Life-Style Epidemiology Unit, Institute for Cancer Research, Prevention and Clinical Network—ISPRO, Florence, Italy
| | - Salvatore Panico
- Dipartimento di Medicina Clinica e Chirurgia, Federico II University, Naples, Italy
| | | | - Olov Rolandsson
- Department of Public Health and Clinical Medicine, Umeå University, Sweden
| | - Carlotta Sacerdote
- Unit of Cancer Epidemiology, Citta’della Salute e della Scienza Hospital-University of Turin and Center for Cancer Prevention (CPO), Torino, Italy
- Human Genetics Foundation (HuGeF), Torino, Italy
| | - Mariá-José Sánchez
- CIBER de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Andalusian School of Public Health, Granada, Spain
| | - Mohammad Sediq Sahrai
- Section of Nutrition and Metabolism, International Agency for Research on Cancer (IARC-WHO), Lyon, France
| | - Ruth Schübel
- German Cancer Research Center [DKFZ], Heidelberg, Germany
| | - Ivonne Sluijs
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | | | | | - Tammy Y N Tong
- Cancer Epidemiology Unit, University of Oxford, Oxford, United Kingdom
| | - Rosario Tumino
- Cancer Registry and Histopathology Unit, ‘Civile – M.P. Arezzo’ Hospital, Ragusa, Italy
- Associazone Iblea per la Ricerca Epidemiologica—Onlus, Ragusa, Italy
| | - Elio Riboli
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, United Kingdom
| | | | - Stephen J Sharp
- MRC Epidemiology Unit, University of Cambridge, United Kingdom
| | - Nita G Forouhi
- MRC Epidemiology Unit, University of Cambridge, United Kingdom
| | - Matthias B Schulze
- Department of Molecular Epidemiology, German Institute of Human Nutrition Potsdam-Rehbruecke, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
- Institute of Nutritional Sciences, University of Potsdam, Nuthetal, Germany
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The Potential of South African Herbal Tisanes, Rooibos and Honeybush in the Management of Type 2 Diabetes Mellitus. Molecules 2018; 23:molecules23123207. [PMID: 30563087 PMCID: PMC6321617 DOI: 10.3390/molecules23123207] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/21/2018] [Accepted: 11/30/2018] [Indexed: 12/15/2022] Open
Abstract
Diabetes mellitus is a metabolic disease that can lead to high morbidity, mortality and long-term complications. Available treatment strategies, which are mainly based on treating hyperglycemia, with insulin and other pharmacological agents are not completely efficient and can even lead to development of unwanted side effects. Scientific evidence suggests that bioactive compounds from teas and other plant-based foods, which are known source of natural antioxidants, could be an attractive strategy to preferentially treat and manage type 2 diabetes mellitus (T2DM) and thus, have significant therapeutic implications. In this review, we attempt an in-depth analysis and discussion of the current progress in our understanding of the antidiabetic potential of two commercialized South Africa herbal tisanes—Rooibos and Honeybush and their polyphenols.
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Liu X, Xu W, Cai H, Gao YT, Li H, Ji BT, Shu X, Wang T, Gerszten RE, Zheng W, Xiang YB, Shu XO. Green tea consumption and risk of type 2 diabetes in Chinese adults: the Shanghai Women's Health Study and the Shanghai Men's Health Study. Int J Epidemiol 2018; 47:1887-1896. [PMID: 30169796 PMCID: PMC6280927 DOI: 10.1093/ije/dyy173] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/30/2018] [Indexed: 12/23/2022] Open
Abstract
Background Epidemiological evidence on the association between tea consumption and the risk of type 2 diabetes (T2D) is inconsistent. This study prospectively investigated whether green tea drinking affects the risk of T2D. Methods This study included participants from the Shanghai Women's Health Study (N = 67 058) and the Shanghai Men's Health Study (N = 52 315) without diabetes at study enrolment. Details of tea consumption, including types and amounts, were collected at the baseline and follow-up survey. Incident T2D was identified through follow-up surveys. Plasma level of caffeine metabolite was measured in a nested case-control study involving 592 diabetes case-control pairs. Cox regression analysis, with tea drinking as a time-dependent variable and covariates adjusted for by a propensity score, was applied to estimate the hazard ratio (HR) and 95% confidence interval (CI) for T2D risk. Logistic regression analysis was applied to evaluate the association between caffeine metabolites and T2D risk. Results Current green tea drinkers had an increased risk of T2D compared with non-current drinkers [HR = 1.20 (95% CI = 1.14-1.27)], and a dose-response relationship was observed for duration of drinking tea and the amount of tea consumed [P for trend <0.001]. The increased risk associated with green tea drinking was observed in both women and men, across the entire period of follow-up, with HR (95% CI) of 1.08 (0.97-1.19) within 5 years of follow-up, 1.22 (1.12-1.32) during the period of 5-10 years of follow-up and 1.16 (1.03-1.30) after 10 years of follow-up. This association did not vary significantly by body mass index, waist-to-hip circumference ratio or smoking status. Plasma level of caffeine was also associated with increased diabetes risk (P = 0.03), confirming the results based on self-reported tea drinking. Conclusions Green tea drinking was associated with an increased risk of T2D in Chinese adults. The mechanisms underlying the association need to be elucidated.
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Affiliation(s)
- Xiaona Liu
- Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China
| | - Wanghong Xu
- Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China
| | - Hui Cai
- Division of Epidemiology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Yu-Tang Gao
- Department of Epidemiology, Shanghai Jiaotong University Renji Hospital, Shanghai, China
| | - Honglan Li
- Department of Epidemiology, Shanghai Jiaotong University Renji Hospital, Shanghai, China
| | - Bu-Tian Ji
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, USA
| | - Xiang Shu
- Division of Epidemiology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Thomas Wang
- Division of Cardiovascular Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Robert E Gerszten
- Division of Cardiovascular Medicine, Beth Israel Deaconess Hospital, Boston, MA, USA
| | - Wei Zheng
- Division of Epidemiology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Yong-Bing Xiang
- Department of Epidemiology, Shanghai Jiaotong University Renji Hospital, Shanghai, China
| | - Xiao-Ou Shu
- Division of Epidemiology, Vanderbilt University School of Medicine, Nashville, TN, USA
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Xu H, Luo J, Huang J, Wen Q. Flavonoids intake and risk of type 2 diabetes mellitus: A meta-analysis of prospective cohort studies. Medicine (Baltimore) 2018; 97:e0686. [PMID: 29742713 PMCID: PMC5959406 DOI: 10.1097/md.0000000000010686] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Epidemiological studies exploring the role of flavonoids intake in preventing type 2 diabetes mellitus (T2DM) showed inconsistent results. Therefore, we performed a meta-analysis of relevant studies to examine the relationship between flavonoids intake and risk of T2DM. We hypothesized that flavonoids intake may decrease the risk of developing T2DM.A systematical search in PubMed and Embase until September 2017 was performed to identify eligible prospective cohort studies. The summary relative risks (RRs) and 95% confidence intervals (CIs) were calculated using random-effect models. Dose-response pattern between total flavonoids intake and T2DM risk was also estimated.Eight prospective studies were included with 312,015 participants, of whom 19,953 developed T2DM during the follow-up periods of 4 to 28 years. Compared with lower consumption, high intake of total flavonoids was associated with a decreased risk of T2DM (RR: 0.89, 95% CI: 0.82-0.96). Among flavonoid subclasses, inverse correlations with T2DM were achieved for intakes of anthocyanidins, flavan-3-ols, flavonols, and isoflavones. Dose-response meta-analysis indicated a curvilinear relationship between total flavonoids intake and incident T2DM (P for nonlinearity = .042), with a significant risk reduction at an intake of ≥550 mg/day. When assuming a linear pattern, the risk of T2DM was decreased by 5% for each 300-mg/day increment in total flavonoids intake (RR: 0.95, 95% CI: 0.93-0.97).Our study suggests that higher intakes of total flavonoids and subclasses (anthocyanidins, flavan-3-ols, flavonols, and isoflavones) are associated with lower risk of T2DM.
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Affiliation(s)
- Hui Xu
- Department of Endocrinology
| | | | - Jia Huang
- The Second Department of Oncology, The Central Hospital of Enshi Autonomous Prefecture, Enshi, China
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Alkhalidy H, Wang Y, Liu D. Dietary Flavonoids in the Prevention of T2D: An Overview. Nutrients 2018; 10:nu10040438. [PMID: 29614722 PMCID: PMC5946223 DOI: 10.3390/nu10040438] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/15/2018] [Accepted: 03/29/2018] [Indexed: 12/16/2022] Open
Abstract
Type 2 diabetes (T2D) is a progressive metabolic disease that is increasing in prevalence globally. It is well established that insulin resistance (IR) and a progressive decline in functional β-cell mass are hallmarks of developing T2D. Obesity is a leading pathogenic factor for developing IR. Constant IR will progress to T2D when β-cells are unable to secret adequate amounts of insulin to compensate for decreased insulin sensitivity. Recently, a considerable amount of research has been devoted to identifying naturally occurring anti-diabetic compounds that are abundant in certain types of foods. Flavonoids are a group of polyphenols that have drawn great interest for their various health benefits. Results from many clinical and animal studies demonstrate that dietary intake of flavonoids might be helpful in preventing T2D, although cellular and molecular mechanisms underlying these effects are still not completely understood. This review discusses our current understanding of the pathophysiology of T2D and highlights the potential anti-diabetic effects of flavonoids and mechanisms of their actions.
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Affiliation(s)
- Hana Alkhalidy
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA.
- Department of Nutrition and Food Technology, Faculty of Agriculture, Jordan University of Science and Technology, Irbid 22110, Jordan.
| | - Yao Wang
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA.
| | - Dongmin Liu
- Department of Human Nutrition, Foods and Exercise, College of Agricultural and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA.
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Dietary polyphenol intake and risk of type 2 diabetes in the Polish arm of the Health, Alcohol and Psychosocial factors in Eastern Europe (HAPIEE) study. Br J Nutr 2017; 118:60-68. [PMID: 28799519 PMCID: PMC5565930 DOI: 10.1017/s0007114517001805] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This study aimed to test the association between dietary content of total and individual
classes of polyphenols and incident cases of type 2 diabetes in Polish adults
participating to the Health, Alcohol and Psychosocial factors In Eastern Europe study. At
baseline, diet by 148-item FFQ and health information were collected from 5806
participants free of diabetes. Self-reported incident type 2 diabetes was ascertained at
2–4-year follow-up visit. OR and 95 % CI of type 2 diabetes comparing the various
categories of polyphenol intake to the lowest one (reference category) and as 1
sd increase modelled as continuous variable were calculated by performing age-,
energy-, and multivariate-adjusted logistic regression models. During the follow-up, 456
incident cases of type 2 diabetes occurred. When comparing extreme quartiles, intake of
total polyphenol was inversely associated with the risk of type 2 diabetes (OR 0·43; 95 %
CI 0·30, 0·61); 1 sd increase was associated with a reduced risk of diabetes (OR
0·68; 95 % CI 0·59, 0·79). Among the main classes of polyphenols, flavonoids, phenolic
acids, and stilbenes were independent contributors to this association. Both subclasses of
phenolic acids were associated with decreased risk of type 2 diabetes, whereas among
subclasses of flavonoids, high intake of flavanols, flavanones, flavones and anthocyanins
was significantly associated with decreased risk of type 2 diabetes. Total dietary
polyphenols and some classes of dietary polyphenols were associated with lower risk of
type 2 diabetes.
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Yang K, Chan CB. Proposed mechanisms of the effects of proanthocyanidins on glucose homeostasis. Nutr Rev 2017; 75:642-657. [DOI: 10.1093/nutrit/nux028] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Bawaked RA, Schröder H, Ribas-Barba L, Cárdenas G, Peña-Quintana L, Pérez-Rodrigo C, Fíto M, Serra-Majem L. Dietary flavonoids of Spanish youth: intakes, sources, and association with the Mediterranean diet. PeerJ 2017; 5:e3304. [PMID: 28533962 PMCID: PMC5437861 DOI: 10.7717/peerj.3304] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 04/12/2017] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Plant-based diets have been linked to high diet quality and reduced risk of cardiovascular diseases. The health impact of plant-based diets might be partially explained by the concomitant intake of flavonoids. Estimation of flavonoids intake in adults has been important for the development of dietary recommendations and interventions for the prevention of weight gain and its consequences. However, estimation of flavonoids intake in children and adolescents is limited. METHODS Average daily intake and sources of flavonoids were estimated for a representative national sample of 3,534 children and young people in Spain, aged 2-24 years. The data was collected between 1998 and 2000 by 24-h recalls. The Phenol-Explorer database and the USDA database on flavonoids content were used. Adherence to the Mediterranean diet was measured by the KIDMED index. RESULTS The mean and median intakes of total flavonoids were 70.7 and 48.1 mg/day, respectively. The most abundant flavonoid class was flavan-3-ols (35.7%), with fruit being the top food source of flavonoids intake (42.8%). Total flavonoids intake was positively associated with the KIDMED index (p < 0.001). CONCLUSION The results of this study provide primary information about flavonoids intake and main food sources in Spanish children, adolescents and young adults. Participants with high daily mean intake of flavonoids have higher adherence to the Mediterranean diet.
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Affiliation(s)
- Rowaedh Ahmed Bawaked
- Cardiovascular Risk and Nutrition Research Group (CARIN), Hospital del Mar Medical Research Institute (IMIM), Barcelona, Spain
- Department of Experimental and Health Sciences, University of Pompeu Fabra, Barcelona, Spain
| | - Helmut Schröder
- Cardiovascular Risk and Nutrition Research Group (CARIN), Hospital del Mar Medical Research Institute (IMIM), Barcelona, Spain
- CIBER Epidemiology and Public Health (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain
| | - Lourdes Ribas-Barba
- Fundación para la Investigación Nutricional (Nutrition Research Foundation), Barcelona, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
| | - Gabriela Cárdenas
- Cardiovascular Risk and Nutrition Research Group (CARIN), Hospital del Mar Medical Research Institute (IMIM), Barcelona, Spain
- Department of Experimental and Health Sciences, University of Pompeu Fabra, Barcelona, Spain
| | - Luis Peña-Quintana
- CIBER Physiopathology of Obesity and Nutrition (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
- Reseach Institute of Biomedical and Health Sciences, University of Las Palmas de Gran Canaria, Gran Canaria, Spain
| | - Carmen Pérez-Rodrigo
- FIDEC Foundation, University of the Basque Country (UPV/EHU) Bilbao, Bilbao, Spain
| | - Montserrat Fíto
- Cardiovascular Risk and Nutrition Research Group (CARIN), Hospital del Mar Medical Research Institute (IMIM), Barcelona, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
| | - Lluis Serra-Majem
- CIBER Physiopathology of Obesity and Nutrition (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
- Reseach Institute of Biomedical and Health Sciences, University of Las Palmas de Gran Canaria, Gran Canaria, Spain
- Department of Nutrition, Food Sciences and Gastronomy, University of Barcelona, Barcelona, Spain
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Huang L, Lerro C, Yang T, Li J, Qiu J, Qiu W, He X, Cui H, Lv L, Xu R, Xu X, Huang H, Liu Q, Zhang Y. Maternal tea consumption and the risk of preterm delivery in urban China: a birth cohort study. BMC Public Health 2016; 16:456. [PMID: 27246202 PMCID: PMC4886392 DOI: 10.1186/s12889-016-3100-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 05/13/2016] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND Studies investigating the relationship between maternal tea drinking and risk of preterm birth have reached inconsistent results. METHODS The present study analyzed data from a birth cohort study including 10,179 women who delivered a singleton live birth were conducted in Lanzhou, China between 2010 and 2012. RESULTS Drinking tea (OR = 1.36, 95 % CI: 1.09-1.69), and specifically green (OR = 1.42, 95 % CI: 1.08-1.85) or scented tea (OR = 1.61, 95 % CI: 1.04-2.50), was associated with an increased risk of preterm birth. Drinking tea was associated with both moderate preterm (OR = 1.41, 95 % CI: 1.12-1.79) and spontaneous preterm birth (OR = 1.41, 95 % CI: 1.09-1.83). Risk of preterm birth increased with decreasing age of starting tea drinking (<20 years, OR = 1.60, 95 % CI: 1.17-2.20) and increasing duration (p for trend < 0.01). The relationship between tea drinking and preterm birth is modified by both maternal age (p < 0.05) and gestational weight gain (p < 0.05). CONCLUSIONS Despite conflicting findings in the previous literature, we saw a significant association with maternal tea drinking and risk of preterm birth in our cohort. More studies are needed both to confirm this finding and to elucidate the mechanism behind this association.
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Affiliation(s)
- Lei Huang
- Gansu Provincial Maternity and Child Care Hospital, 143 North Road Qilihe District, Lanzhou, Gansu Province, 730050, China
| | - Catherine Lerro
- Yale University, School of Public Health, 60 College Street LEPH 440, New haven, CT, 06520, USA
| | - Tao Yang
- Gansu Provincial Maternity and Child Care Hospital, 143 North Road Qilihe District, Lanzhou, Gansu Province, 730050, China
| | - Jing Li
- Gansu Provincial Maternity and Child Care Hospital, 143 North Road Qilihe District, Lanzhou, Gansu Province, 730050, China
| | - Jie Qiu
- Gansu Provincial Maternity and Child Care Hospital, 143 North Road Qilihe District, Lanzhou, Gansu Province, 730050, China
| | - Weitao Qiu
- Gansu Provincial Maternity and Child Care Hospital, 143 North Road Qilihe District, Lanzhou, Gansu Province, 730050, China
| | - Xiaochun He
- Gansu Provincial Maternity and Child Care Hospital, 143 North Road Qilihe District, Lanzhou, Gansu Province, 730050, China
| | - Hongmei Cui
- Gansu Provincial Maternity and Child Care Hospital, 143 North Road Qilihe District, Lanzhou, Gansu Province, 730050, China
| | - Ling Lv
- Gansu Provincial Maternity and Child Care Hospital, 143 North Road Qilihe District, Lanzhou, Gansu Province, 730050, China
| | - Ruifeng Xu
- Gansu Provincial Maternity and Child Care Hospital, 143 North Road Qilihe District, Lanzhou, Gansu Province, 730050, China
| | - Xiaoying Xu
- Gansu Provincial Maternity and Child Care Hospital, 143 North Road Qilihe District, Lanzhou, Gansu Province, 730050, China
| | - Huang Huang
- Yale University, School of Public Health, 60 College Street LEPH 440, New haven, CT, 06520, USA
| | - Qing Liu
- Gansu Provincial Maternity and Child Care Hospital, 143 North Road Qilihe District, Lanzhou, Gansu Province, 730050, China.
| | - Yawei Zhang
- Yale University, School of Public Health, 60 College Street LEPH 440, New haven, CT, 06520, USA.
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Feng L, Chong MS, Lim WS, Gao Q, Nyunt MS, Lee TS, Collinson SL, Tsoi T, Kua EH, Ng TP. Tea Consumption Reduces the Incidence of Neurocognitive Disorders: Findings from the Singapore Longitudinal Aging Study. J Nutr Health Aging 2016; 20:1002-1009. [PMID: 27925140 DOI: 10.1007/s12603-016-0687-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
OBJECTIVES To examine the relationships between tea consumption habits and incident neurocognitive disorders (NCD) and explore potential effect modification by gender and the apolipoprotein E (APOE) genotype. DESIGN Population-based longitudinal study. SETTING The Singapore Longitudinal Aging Study (SLAS). PARTICIPANTS 957 community-living Chinese elderly who were cognitively intact at baseline. MEASUREMENTS We collected tea consumption information at baseline from 2003 to 2005 and ascertained incident cases of neurocognitive disorders (NCD) from 2006 to 2010. Odds ratio (OR) of association were calculated in logistic regression models that adjusted for potential confounders. RESULTS A total of 72 incident NCD cases were identified from the cohort. Tea intake was associated with lower risk of incident NCD, independent of other risk factors. Reduced NCD risk was observed for both green tea (OR=0.43) and black/oolong tea (OR=0.53) and appeared to be influenced by the changing of tea consumption habit at follow-up. Using consistent non-tea consumers as the reference, only consistent tea consumers had reduced risk of NCD (OR=0.39). Stratified analyses indicated that tea consumption was associated with reduced risk of NCD among females (OR=0.32) and APOE ε4 carriers (OR=0.14) but not males and non APOE ε4 carriers. CONCLUSION Regular tea consumption was associated with lower risk of neurocognitive disorders among Chinese elderly. Gender and genetic factors could possibly modulate this association.
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Affiliation(s)
- L Feng
- Dr. Feng, Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore,
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Helm L, Macdonald IA. Impact of beverage intake on metabolic and cardiovascular health. Nutr Rev 2015; 73 Suppl 2:120-9. [DOI: 10.1093/nutrit/nuv049] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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Keske MA, Ng HLH, Premilovac D, Rattigan S, Kim JA, Munir K, Yang P, Quon MJ. Vascular and metabolic actions of the green tea polyphenol epigallocatechin gallate. Curr Med Chem 2015; 22:59-69. [PMID: 25312214 PMCID: PMC4909506 DOI: 10.2174/0929867321666141012174553] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 08/05/2014] [Accepted: 08/05/2014] [Indexed: 01/04/2023]
Abstract
Epidemiological studies demonstrate robust correlations between green tea consumption and reduced risk of type 2 diabetes and its cardiovascular complications. However, underlying molecular, cellular, and physiological mechanisms remain incompletely understood. Health promoting actions of green tea are often attributed to epigallocatechin gallate (EGCG), the most abundant polyphenol in green tea. Insulin resistance and endothelial dysfunction play key roles in the pathogenesis of type 2 diabetes and its cardiovascular complications. Metabolic insulin resistance results from impaired insulin-mediated glucose disposal in skeletal muscle and adipose tissue, and blunted insulin-mediated suppression of hepatic glucose output that is often associated with endothelial/vascular dysfunction. This endothelial dysfunction is itself caused, in part, by impaired insulin signaling in vascular endothelium resulting in reduced insulin-stimulated production of NO in arteries, and arterioles that regulate nutritive capillaries. In this review, we discuss the considerable body of literature supporting insulin-mimetic actions of EGCG that oppose endothelial dysfunction and ameliorate metabolic insulin resistance in skeletal muscle and liver. We conclude that EGCG is a promising therapeutic to combat cardiovascular complications associated with the metabolic diseases characterized by reciprocal relationships between insulin resistance and endothelial dysfunction that include obesity, metabolic syndrome and type 2 diabetes. There is a strong rationale for well-powered randomized placebo controlled intervention trials to be carried out in insulin resistant and diabetic populations.
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Affiliation(s)
| | | | | | | | | | | | | | - Michael J Quon
- Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, 7000, Australia.
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Yang J, Mao QX, Xu HX, Ma X, Zeng CY. Tea consumption and risk of type 2 diabetes mellitus: a systematic review and meta-analysis update. BMJ Open 2014; 4:e005632. [PMID: 25052177 PMCID: PMC4120344 DOI: 10.1136/bmjopen-2014-005632] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVE Tea has been suggested to decrease blood glucose levels and protect pancreatic β cells in diabetic mice. However, human epidemiological studies showed inconsistent results for the association between tea consumption and type 2 diabetes mellitus (T2DM) risk. The aim of this study was to conduct a meta-analysis to further explore the association between tea consumption and incidence of T2DM. DESIGN Systematic review and meta-analysis. METHODS We performed a systematic literature search up to 30 August 2013 in PubMed, EMBASE, Chinese Wanfang Database and CNKI database. Pooling relative risks (RRs) were estimated by random-effect models. Two kinds of subgroup analyses (according to sex and regions) were performed. Sensitive analyses were performed according to types of tea. RESULTS Overall, no statistically significant relationship between tea consumption and risk of T2DM was found based on 12 eligible studies (pooling RR 0.99, 95% CI 0.95 to 1.03). Compared with the lowest/non-tea group, daily tea consumption (≥3 cups/day) was associated with a lower T2DM risk (RR 0.84, 95% CI 0.73 to 0.97). Subgroup analyses showed a difference between men and women. Overall, the RRs (95% CI) were 0.92 (0.84 to 1.00) for men, and 1.00 (0.96 to 1.05) for women, respectively. Tea consumption of ≥3 cups/day was associated with decreased T2DM risk in women (RR 0.84, 95% CI 0.71 to 1.00). Overall, the RRs (95% CIs) were 0.84 (0.71 to 1.00) for Asians, and 1.00 (0.97 to 1.04) for Americans and Europeans, respectively. No obvious change was found in sensitivity analyses. CONCLUSIONS The results suggest that daily tea consumption (≥3 cups/day) is associated with a lower T2DM risk. However, further studies are needed to enrich related evidence, especially with regard to types of tea or sex.
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Affiliation(s)
- Jian Yang
- Department of Nutrition, Daping Hospital, The Third Military Medical University, Chongqing, People's Republic of China
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, People's Republic of China
| | - Qun-Xia Mao
- Social Medical Science Research Centre, National Research Institute for Family Planning, Beijing, People's Republic of China
| | - Hong-Xia Xu
- Department of Nutrition, Daping Hospital, The Third Military Medical University, Chongqing, People's Republic of China
| | - Xu Ma
- National Research Institute for Family Planning, Beijing, People's Republic of China
| | - Chun-Yu Zeng
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, People's Republic of China
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Hinkle SN, Laughon SK, Catov JM, Olsen J, Bech BH. First trimester coffee and tea intake and risk of gestational diabetes mellitus: a study within a national birth cohort. BJOG 2014; 122:420-8. [PMID: 24947484 DOI: 10.1111/1471-0528.12930] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/25/2014] [Indexed: 12/24/2022]
Abstract
OBJECTIVE Coffee and tea consumption is associated with a decreased type 2 diabetes risk in non-pregnant adults. We examined the relation between first trimester coffee and tea consumption and gestational diabetes mellitus (GDM) risk. DESIGN Population-based cohort study. SETTING Denmark 1996-2002. POPULATION Non-diabetic women with singleton pregnancies in the Danish National Birth Cohort (n = 71,239). METHODS Estimated adjusted relative risks (RR) and 95% confidence intervals (95%CI) for the association between first trimester coffee and tea or estimated total caffeine and GDM. MAIN OUTCOME MEASURES GDM ascertained from the National Hospital Discharge Register or maternal interview. RESULTS Coffee or tea intake was reported in 81.2% (n = 57,882) and 1.3% (n = 912) of pregnancies were complicated by GDM. Among non-consumers, 1.5% of pregnancies were complicated by GDM. Among coffee drinkers, GDM was highest among women who drank ≥8 cups/day (1.8%) with no significant difference across intake levels (P = 0.10). Among tea drinkers, there was no difference in GDM across intake levels (1.2%; P = 0.98). After adjustment for age, socio-occupational status, parity, pre-pregnancy body mass index, smoking, and cola, there was suggestion of a protective, but non-significant association with increasing coffee (RR ≥8 versus 0 cups/day = 0.89 [95%CI 0.64-1.25]) and tea (RR ≥8 versus 0 cups/day = 0.77 [95%CI 0.55-1.08]). Results were similar by smoking status, except a non-significant 1.45-fold increased risk with ≥8 coffee cups/day for non-smokers. There was a non-significant reduced GDM risk with increasing total caffeine. CONCLUSIONS Our results suggest that moderate first trimester coffee and tea intake were not associated with GDM increased risk and possibly may have a protective effect.
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Affiliation(s)
- S N Hinkle
- Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
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Liu CY, Huang CJ, Huang LH, Chen IJ, Chiu JP, Hsu CH. Effects of green tea extract on insulin resistance and glucagon-like peptide 1 in patients with type 2 diabetes and lipid abnormalities: a randomized, double-blinded, and placebo-controlled trial. PLoS One 2014; 9:e91163. [PMID: 24614112 PMCID: PMC3948786 DOI: 10.1371/journal.pone.0091163] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2013] [Accepted: 01/10/2014] [Indexed: 12/25/2022] Open
Abstract
UNLABELLED The aim of this study is to investigate the effect of green tea extract on patients with type 2 diabetes mellitus and lipid abnormalities on glycemic and lipid profiles, and hormone peptides by a double-blinded, randomized and placebo-controlled clinical trial. This trial enrolled 92 subjects with type 2 diabetes mellitus and lipid abnormalities randomized into 2 arms, each arm comprising 46 participants. Of the participants, 39 in therapeutic arm took 500 mg green tea extract, three times a day, while 38 in control arm took cellulose with the same dose and frequency to complete the 16-week study. Anthropometrics measurements, glycemic and lipid profiles, safety parameters, and obesity-related hormone peptides were analyzed at screening and after 16-week course. Within-group comparisons showed that green tea extract caused a significant decrease in triglyceride and homeostasis model assessment of insulin resistance index after 16 weeks. Green tea extract also increased significantly high density lipoprotein cholesterol. The HOMA-IR index decreased from 5.4±3.9 to 3.5±2.0 in therapeutic arm only. Adiponectin, apolipoprotein A1, and apolipoprotein B100 increased significantly in both arms, but only glucagon-like peptide 1 increased in the therapeutic arm. However, only decreasing trend in triglyceride was found in between-group comparison. Our study suggested that green tea extract significantly improved insulin resistance and increased glucagon-like peptide 1 only in within-group comparison. The potential effects of green tea extract on insulin resistance and glucagon-like peptide 1 warrant further investigation. TRIAL REGISTRATION ClinicalTrials.gov NCT01360567.
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Affiliation(s)
- Chia-Yu Liu
- Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
- Department of Chinese Medicine, Branch of Linsen and Chinese Medicine, Taipei City Hospital, Taipei, Taiwan
| | - Chien-Jung Huang
- Department of Metabolism, Branch of Linsen and Chinese Medicine, Taipei City Hospital, Taipei, Taiwan
| | - Lin-Huang Huang
- Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - I-Ju Chen
- Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
- Department of Chinese Medicine, Branch of Linsen and Chinese Medicine, Taipei City Hospital, Taipei, Taiwan
| | - Jung-Peng Chiu
- Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
- Department of Chinese Medicine, Branch of Linsen and Chinese Medicine, Taipei City Hospital, Taipei, Taiwan
| | - Chung-Hua Hsu
- Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
- Department of Chinese Medicine, Branch of Linsen and Chinese Medicine, Taipei City Hospital, Taipei, Taiwan
- * E-mail:
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Zamora-Ros R, Forouhi NG, Sharp SJ, González CA, Buijsse B, Guevara M, van der Schouw YT, Amiano P, Boeing H, Bredsdorff L, Fagherazzi G, Feskens EJ, Franks PW, Grioni S, Katzke V, Key TJ, Khaw KT, Kühn T, Masala G, Mattiello A, Molina-Montes E, Nilsson PM, Overvad K, Perquier F, Redondo ML, Ricceri F, Rolandsson O, Romieu I, Roswall N, Scalbert A, Schulze M, Slimani N, Spijkerman AMW, Tjonneland A, Tormo MJ, Touillaud M, Tumino R, van der A DL, van Woudenbergh GJ, Langenberg C, Riboli E, Wareham NJ. Dietary intakes of individual flavanols and flavonols are inversely associated with incident type 2 diabetes in European populations. J Nutr 2014; 144:335-43. [PMID: 24368432 PMCID: PMC3927546 DOI: 10.3945/jn.113.184945] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 10/14/2013] [Accepted: 12/06/2013] [Indexed: 12/25/2022] Open
Abstract
Dietary flavanols and flavonols, flavonoid subclasses, have been recently associated with a lower risk of type 2 diabetes (T2D) in Europe. Even within the same subclass, flavonoids may differ considerably in bioavailability and bioactivity. We aimed to examine the association between individual flavanol and flavonol intakes and risk of developing T2D across European countries. The European Prospective Investigation into Cancer and Nutrition (EPIC)-InterAct case-cohort study was conducted in 8 European countries across 26 study centers with 340,234 participants contributing 3.99 million person-years of follow-up, among whom 12,403 incident T2D cases were ascertained and a center-stratified subcohort of 16,154 individuals was defined. We estimated flavonoid intake at baseline from validated dietary questionnaires using a database developed from Phenol-Explorer and USDA databases. We used country-specific Prentice-weighted Cox regression models and random-effects meta-analysis methods to estimate HRs. Among the flavanol subclass, we observed significant inverse trends between intakes of all individual flavan-3-ol monomers and risk of T2D in multivariable models (all P-trend < 0.05). We also observed significant trends for the intakes of proanthocyanidin dimers (HR for the highest vs. the lowest quintile: 0.81; 95% CI: 0.71, 0.92; P-trend = 0.003) and trimers (HR: 0.91; 95% CI: 0.80, 1.04; P-trend = 0.07) but not for proanthocyanidins with a greater polymerization degree. Among the flavonol subclass, myricetin (HR: 0.77; 95% CI: 0.64, 0.93; P-trend = 0.001) was associated with a lower incidence of T2D. This large and heterogeneous European study showed inverse associations between all individual flavan-3-ol monomers, proanthocyanidins with a low polymerization degree, and the flavonol myricetin and incident T2D. These results suggest that individual flavonoids have different roles in the etiology of T2D.
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Affiliation(s)
- Raul Zamora-Ros
- Unit of Nutrition, Environment, and Cancer, Catalan Institute of Oncology (ICO), Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain
| | - Nita G. Forouhi
- MRC Epidemiology Unit, University of Cambridge, Institute of Metabolic Science, Cambridge, UK
| | - Stephen J. Sharp
- MRC Epidemiology Unit, University of Cambridge, Institute of Metabolic Science, Cambridge, UK
| | - Carlos A. González
- Unit of Nutrition, Environment, and Cancer, Catalan Institute of Oncology (ICO), Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain
| | - Brian Buijsse
- Department of Epidemiology, German Institute of Human Nutrition Potsdam–Rehbrücke, Nuthetal, Germany
| | - Marcela Guevara
- Public Health Institute of Navarra, Pamplona, Spain
- CIBER Epidemiology and Public Health (CIBERESP), Madrid, Spain
| | - Yvonne T. van der Schouw
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Pilar Amiano
- CIBER Epidemiology and Public Health (CIBERESP), Madrid, Spain
- Public Health Department of Gipuzkoa, BioDonostia Research Institute, Health Department of the Basque Region, San Sebastián, Spain
| | - Heiner Boeing
- Department of Epidemiology, German Institute of Human Nutrition Potsdam–Rehbrücke, Nuthetal, Germany
| | - Lea Bredsdorff
- National Food Institute, Technical University of Denmark, Moerkhoej, Denmark
| | - Guy Fagherazzi
- INSERM, Centre for Research in Epidemiology and Population Health (CESP), U1018, Nutrition, Hormones and Women's Health, Villejuif, France
- Paris South University, UMRS 1018, Villejuif, France
| | - Edith J. Feskens
- Division of Human Nutrition–Section of Nutrition and Epidemiology, University of Wageningen, Wageningen, The Netherlands
| | - Paul W. Franks
- Genetic and Molecular Epidemiology Unit, Clinical Research Center, Skåne University Hospital, Lund University, Malmö, Sweden
| | - Sara Grioni
- Nutritional Epidemiology Unit, IRCCS Foundation National Institute of Oncology, Milan, Italy
| | - Verena Katzke
- Department of Cancer Epidemiology, German Cancer Research Center, Heidelberg, Germany
| | - Timothy J. Key
- Cancer Epidemiology Unit, University of Oxford, Oxford, UK
| | - Kay-Tee Khaw
- Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Tilman Kühn
- Department of Cancer Epidemiology, German Cancer Research Center, Heidelberg, Germany
| | - Giovanna Masala
- Molecular and Nutritional Epidemiology Unit, Cancer Research and Prevention Institute–ISPO, Florence, Italy
| | - Amalia Mattiello
- Department of Clinical Medicine and Surgery, Federico II University, Naples, Italy
| | - Esther Molina-Montes
- CIBER Epidemiology and Public Health (CIBERESP), Madrid, Spain
- Andalusian School of Public Health, Granada, Spain
| | | | - Kim Overvad
- Section for Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Florence Perquier
- INSERM, Centre for Research in Epidemiology and Population Health (CESP), U1018, Nutrition, Hormones and Women's Health, Villejuif, France
- Paris South University, UMRS 1018, Villejuif, France
| | | | | | - Olov Rolandsson
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | - Isabelle Romieu
- Section of Nutrition and Metabolism, International Agency for Research on Cancer (IARC), Lyon, France
| | - Nina Roswall
- Institute of Cancer Epidemiology, Danish Cancer Society, Copenhagen, Denmark
| | - Augustin Scalbert
- Section of Nutrition and Metabolism, International Agency for Research on Cancer (IARC), Lyon, France
| | - Matthias Schulze
- Department of Molecular Epidemiology, German Institute of Human Nutrition Potsdam–Rehbrücke, Nuthetal, Germany
| | - Nadia Slimani
- Section of Nutrition and Metabolism, International Agency for Research on Cancer (IARC), Lyon, France
| | | | - Anne Tjonneland
- Institute of Cancer Epidemiology, Danish Cancer Society, Copenhagen, Denmark
| | - Maria Jose Tormo
- CIBER Epidemiology and Public Health (CIBERESP), Madrid, Spain
- Epidemiology Department, Murcia Regional Health Council, Murcia, Spain
- Department of Health and Social Sciences, Universidad de Murcia, Murcia, Spain
| | - Marina Touillaud
- INSERM, Centre for Research in Epidemiology and Population Health (CESP), U1018, Nutrition, Hormones and Women's Health, Villejuif, France
- Paris South University, UMRS 1018, Villejuif, France
| | - Rosario Tumino
- Cancer Registry and Histopathology Unit, “Civile M.P. Arezzo” Hospital, Ragusa, Italy; and
| | - Daphne L. van der A
- National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Geertruida J. van Woudenbergh
- Division of Human Nutrition–Section of Nutrition and Epidemiology, University of Wageningen, Wageningen, The Netherlands
| | - Claudia Langenberg
- MRC Epidemiology Unit, University of Cambridge, Institute of Metabolic Science, Cambridge, UK
| | - Elio Riboli
- School of Public Health, Imperial College London, London, UK
| | - Nicholas J. Wareham
- MRC Epidemiology Unit, University of Cambridge, Institute of Metabolic Science, Cambridge, UK
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Interaction of some commercial teas with some carbohydrate metabolizing enzymes linked with type-2 diabetes: a dietary intervention in the prevention of type-2 diabetes. Adv Prev Med 2014; 2014:534082. [PMID: 24527218 PMCID: PMC3914286 DOI: 10.1155/2014/534082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 12/13/2013] [Indexed: 02/04/2023] Open
Abstract
This study is aimed at assessing the inhibitory effect of teas on key enzymes (α-amylase and α-glucosidase) linked with type-2 diabetes and their antioxidant properties. Four samples of three brands were used; infusions of green tea (GT), 2 brands of black tea (BT), and a formulated herbal preparation for diabetes (ADT) (white tea, Radix Puerariae, Radix ophiopogonis, hawthorn berry, Chinese yam, and fragrant Solomon seal rhizome) were prepared and subsequently analyzed for their total phenol, ascorbic acid contents, antioxidant properties (2,2-Azizobis
(3-Ethylbenzo-Thiazoline~6-sulfonate) “ABTS” scavenging ability and ferric reducing antioxidant property), and inhibition of pancreatic-α-amylase and intestinal-α-glucosidase in vitro. The study revealed that GT had the highest total phenol content, ascorbic acid content, ABTS∗ scavenging ability, and ferric reducing ability. Furthermore, all the teas inhibited Fe2+ and sodium nitroprusside induced lipid peroxidation in pancreas, with GT having the highest inhibitory effect. Conversely, there was no significant difference (P > 0.05) in the inhibitory effects of the teas on α-amylase and α-glucosidase. The antidiabetic property of the teas could be attributed to their inhibitory effect on carbohydrate hydrolyzing enzymes implicated in diabetes and their antioxidant activities.
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Tamayo T, Rosenbauer J, Wild SH, Spijkerman AMW, Baan C, Forouhi NG, Herder C, Rathmann W. Diabetes in Europe: an update. Diabetes Res Clin Pract 2014; 103:206-17. [PMID: 24300019 DOI: 10.1016/j.diabres.2013.11.007] [Citation(s) in RCA: 156] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Diabetes is among the leading causes of death in the IDF Europe Region (EUR), continues to increase in prevalence with diabetic macro- and microvascular complications resulting in increased disability and enormous healthcare costs. In 2013, the number of people with diabetes is estimated to be 56 million in EUR with an overall estimated prevalence of 8.5%. However, estimates of diabetes prevalence in 2013 vary widely in the 56 diverse countries in EUR from 2.4% in Moldova to 14.9% in Turkey. Trends in diabetes prevalence also vary between countries with stable prevalence since 2002 for many countries but a doubling of diabetes prevalence in Turkey. For 2035, a further increase of nearly 10 million people with diabetes is projected for the EUR. Prevalence of type 1 has also increased over the past 20 years in EUR and there was estimated to be 129,350 cases in children aged 0-14 years in 2013. Registries provide valid information on incidence of type 1 diabetes with more complete data available for children than for adults. There are large differences in distribution of risk factors for diabetes at the population level in EUR. Modifiable risk factors such as obesity, physical inactivity, smoking behaviour (including secondhand smoking), environmental pollutants, psychosocial factors and socioeconomic deprivation could be tackled to reduce the incidence of type 2 diabetes in Europe. In addition, diabetes management is a major challenge to health services in the European countries. Improved networking practices of health professionals and other stakeholders in combination with empowerment of people with diabetes and continuous quality monitoring need to be further developed in Europe.
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Affiliation(s)
- T Tamayo
- Institute for Biometrics and Epidemiology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - J Rosenbauer
- Institute for Biometrics and Epidemiology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - S H Wild
- Centre for Population Health Sciences, University of Edinburgh, UK
| | - A M W Spijkerman
- Centre for Nutrition, Prevention and Health Services, National Institute of Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - C Baan
- Centre for Nutrition, Prevention and Health Services, National Institute of Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - N G Forouhi
- Medical Research Council Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - C Herder
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - W Rathmann
- Institute for Biometrics and Epidemiology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany.
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Forouhi NG, Wareham NJ. The EPIC-InterAct Study: A Study of the Interplay between Genetic and Lifestyle Behavioral Factors on the Risk of Type 2 Diabetes in European Populations. Curr Nutr Rep 2014; 3:355-363. [PMID: 25383255 PMCID: PMC4218968 DOI: 10.1007/s13668-014-0098-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The rising prevalence of type 2 diabetes around the world and the global pattern of variation in risk between countries have been widely attributed to an interplay between rising rates of obesity and poor lifestyles, and genetic or developmental susceptibility to disease. Although this general hypothesis has been in existence for more than 50 years, the precise mechanisms that may explain it have remained uncertain. Advances in technology and the application of new methods in large scale population studies have made it possible to study these mechanisms. The InterAct project, funded by the European Commission, is a large case-cohort study which has verified 12,403 incident cases of type 2 diabetes, facilitating the study of genetic and lifestyle factors on the risk of type 2 diabetes among European populations.
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Affiliation(s)
- Nita G. Forouhi
- Medical Research Council Epidemiology Unit, University of Cambridge School of Clinical Medicine, Institute of Metabolic Science, Cambridge Biomedical Campus, Cambridge, CB2 0QQ UK
| | - Nicholas J. Wareham
- Medical Research Council Epidemiology Unit, University of Cambridge School of Clinical Medicine, Institute of Metabolic Science, Cambridge Biomedical Campus, Cambridge, CB2 0QQ UK
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Tea consumption and risk of type 2 diabetes: a dose-response meta-analysis of cohort studies. Br J Nutr 2013; 111:1329-39. [PMID: 24331002 DOI: 10.1017/s0007114513003887] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Tea consumption has inconsistently been shown to be associated with the risk of type 2 diabetes (T2D). The aim of the present study was to conduct a dose-response meta-analysis of cohort studies assessing the association between consumption of tea and risk of developing T2D. Pertinent studies were identified by searching PubMed, Web of Science and EMBASE through 31 March 2013. A total of sixteen cohorts from fifteen articles that reported 37,445 cases of diabetes among 545,517 participants were included. A significant linearly inverse association between tea consumption and T2D risk was found (P for linear trend = 0.02). An increase of 2 cups/d in tea consumption was found to be associated with a 4.6 (95% CI 0.9, 8.1) % reduced risk of T2D. On the basis of the dose-response meta-analysis, the predicted relative risks of diabetes for 0, 1, 2, 3, 4, 5 and 6 cups of tea consumed per d were 1.00 (referent), 0.97 (95% CI 0.94, 1.01), 0.95(95% CI 0.92, 0.98), 0.93 (95% CI 0.88, 0.98), 0.90 (95% CI 0.85, 0.96), 0.88 (95 % CI 0.83, 0.93) and 0.85 (95% CI 0.80, 0.91), respectively. There was a statistically significant heterogeneity within the selected studies (Q= 45.32, P< 0.001, I 2= 60.3 %). No evidence of substantial small-study bias was found (P= 0·46). Our findings suggest that tea consumption could be linearly inversely associated with T2D risk. Future well-designed observational studies that account for different characteristics of tea such as tea types, preparation methods and tea strength are needed to fully characterise such an association.
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Zamora-Ros R, Forouhi NG, Sharp SJ, González CA, Buijsse B, Guevara M, van der Schouw YT, Amiano P, Boeing H, Bredsdorff L, Clavel-Chapelon F, Fagherazzi G, Feskens EJ, Franks PW, Grioni S, Katzke V, Key TJ, Khaw KT, Kühn T, Masala G, Mattiello A, Molina-Montes E, Nilsson PM, Overvad K, Perquier F, Quirós JR, Romieu I, Sacerdote C, Scalbert A, Schulze M, Slimani N, Spijkerman AMW, Tjonneland A, Tormo MJ, Tumino R, van der A DL, Langenberg C, Riboli E, Wareham NJ. The association between dietary flavonoid and lignan intakes and incident type 2 diabetes in European populations: the EPIC-InterAct study. Diabetes Care 2013; 36:3961-70. [PMID: 24130345 PMCID: PMC3836159 DOI: 10.2337/dc13-0877] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To study the association between dietary flavonoid and lignan intakes, and the risk of development of type 2 diabetes among European populations. RESEARCH DESIGN AND METHODS The European Prospective Investigation into Cancer and Nutrition-InterAct case-cohort study included 12,403 incident type 2 diabetes cases and a stratified subcohort of 16,154 participants from among 340,234 participants with 3.99 million person-years of follow-up in eight European countries. At baseline, country-specific validated dietary questionnaires were used. A flavonoid and lignan food composition database was developed from the Phenol-Explorer, the U.K. Food Standards Agency, and the U.S. Department of Agriculture databases. Hazard ratios (HRs) from country-specific Prentice-weighted Cox regression models were pooled using random-effects meta-analysis. RESULTS In multivariable models, a trend for an inverse association between total flavonoid intake and type 2 diabetes was observed (HR for the highest vs. the lowest quintile, 0.90 [95% CI 0.77-1.04]; P value trend = 0.040), but not with lignans (HR 0.88 [95% CI 0.72-1.07]; P value trend = 0.119). Among flavonoid subclasses, flavonols (HR 0.81 [95% CI 0.69-0.95]; P value trend = 0.020) and flavanols (HR 0.82 [95% CI 0.68-0.99]; P value trend = 0.012), including flavan-3-ol monomers (HR 0.73 [95% CI 0.57-0.93]; P value trend = 0.029), were associated with a significantly reduced hazard of diabetes. CONCLUSIONS Prospective findings in this large European cohort demonstrate inverse associations between flavonoids, particularly flavanols and flavonols, and incident type 2 diabetes. This suggests a potential protective role of eating a diet rich in flavonoids, a dietary pattern based on plant-based foods, in the prevention of type 2 diabetes.
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Huang H, Guo Q, Qiu C, Huang B, Fu X, Yao J, Liang J, Li L, Chen L, Tang K, Lin L, Lu J, Bi Y, Ning G, Wen J, Lin C, Chen G. Associations of green tea and rock tea consumption with risk of impaired fasting glucose and impaired glucose tolerance in Chinese men and women. PLoS One 2013; 8:e79214. [PMID: 24260170 PMCID: PMC3832448 DOI: 10.1371/journal.pone.0079214] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2013] [Accepted: 09/18/2013] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVE To explore the associations of green tea and rock tea consumption with risk of impaired fasting glucose (IFG) and impaired glucose tolerance (IGT). METHODS A multistage, stratified, cluster, random-sampling method was used to select a representative sample from Fujian Province in China. In total, 4808 subjects without cardiovascular disease, hypertension, cancer, or pancreatic, liver, kidney, or gastrointestinal diseases were enrolled in the study. A standard questionnaire was used to gather data on tea (green, rock, and black) consumption and other relevant factors. The assessment of impaired glucose regulation (IGR) was using 75-g oral glucose tolerance test (OGTT), the diagnostic criteria of normal glucose tolerance was according to American Diabetes Association. RESULTS Green tea consumption was associated with a lower risk of IFG, while rock tea consumption was associated with a lower risk of IGT. The adjusted odds ratios for IFG for green tea consumption of <1, 1-15, 16-30, and >30 cups per week were 1.0 (reference), 0.42 (95% confidence intervals (CI) 0.27-0.65), 0.23 (95% CI, 0.12-0.46), and 0.41 (95% CI, 0.17-0.93), respectively. The adjusted odds ratios for IGT for rock tea consumption of <1, 1-15, 16-30, and >30 cups per week were 1.0 (reference), 0.69 (95% CI, 0.48-0.98), 0.59 (95% CI, 0.39-0.90), and 0.64 (95% CI, 0.43-0.97), respectively. A U-shaped association was observed, subjects who consumed 16-30 cups of green or rock tea per week having the lowest odds ratios for IFG or IGT. CONCLUSIONS Consumption of green or rock tea may protect against the development of type 2 diabetes mellitus in Chinese men and women, particularly in those who drink 16-30 cups per week.
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Affiliation(s)
- Huibin Huang
- Department of Endocrinology, Fujian Provincial Hospital Key Laboratory of Endocrinology, Fujian Medical University, Fuzhou, Fujian, China
| | - Qiuxuan Guo
- Department of Endocrinology, Fujian Provincial Hospital Key Laboratory of Endocrinology, Fujian Medical University, Fuzhou, Fujian, China
| | - Changsheng Qiu
- Department of Osteology, Wuyishan Municipal Hospital, Fujian Provincial Hospital, Wuyishan, Fujian, China
| | - Baoying Huang
- Department of Endocrinology, Ningde Municipal Hospital, Fujian Medical University, Ningde, Fujian, China
| | - Xianguo Fu
- Department of Endocrinology, Ningde Municipal Hospital, Fujian Medical University, Ningde, Fujian, China
| | - Jin Yao
- Department of Endocrinology, Fujian Provincial Hospital Key Laboratory of Endocrinology, Fujian Medical University, Fuzhou, Fujian, China
| | - Jixing Liang
- Department of Endocrinology, Fujian Provincial Hospital Key Laboratory of Endocrinology, Fujian Medical University, Fuzhou, Fujian, China
| | - Liantao Li
- Department of Endocrinology, Fujian Provincial Hospital Key Laboratory of Endocrinology, Fujian Medical University, Fuzhou, Fujian, China
| | - Ling Chen
- Department of Endocrinology, Fujian Provincial Hospital Key Laboratory of Endocrinology, Fujian Medical University, Fuzhou, Fujian, China
| | - Kaka Tang
- Department of Endocrinology, Fujian Provincial Hospital Key Laboratory of Endocrinology, Fujian Medical University, Fuzhou, Fujian, China
| | - Lixiang Lin
- Department of Endocrinology, Fujian Provincial Hospital Key Laboratory of Endocrinology, Fujian Medical University, Fuzhou, Fujian, China
| | - Jieli Lu
- Department of Endocrinology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yufang Bi
- Department of Endocrinology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Guang Ning
- Department of Endocrinology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Junping Wen
- Department of Endocrinology, Fujian Provincial Hospital Key Laboratory of Endocrinology, Fujian Medical University, Fuzhou, Fujian, China
| | - Caijing Lin
- Department of Emergency, Fujian Provincial Hospital, Fujian Medical University, Fuzhou, Fujian, China
| | - Gang Chen
- Department of Endocrinology, Fujian Provincial Hospital Key Laboratory of Endocrinology, Fujian Medical University, Fuzhou, Fujian, China
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Abstract
PURPOSE OF REVIEW Tea and coffee, after water, are the most commonly consumed beverages in the world and are the top sources of caffeine and antioxidant polyphenols in the American diet. The purpose of this review is to assess the health effects of chronic tea and/or coffee consumption. RECENT FINDINGS Tea consumption, especially green tea, is associated with significantly reduced risks for stroke, diabetes and depression, and improved levels of glucose, cholesterol, abdominal obesity and blood pressure. Habitual coffee consumption in large epidemiological studies is associated with reduced mortality, both for all-cause and cardiovascular deaths. In addition, coffee intake is associated with risks of heart failure, stroke, diabetes mellitus and some cancers in an inverse dose-dependent fashion. Surprisingly, coffee is associated with neutral to reduced risks for both atrial and ventricular arrhythmias. However, caffeine at high doses can increase anxiety, insomnia, calcium loss and possibly the risk of fractures. SUMMARY Coffee and tea can generally be recommended as health-promoting additions to an adult diet. Adequate dietary calcium intake may be particularly important for tea and coffee drinkers.
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Affiliation(s)
- Salman K Bhatti
- aSaint Luke's Mid America Heart Institute & University of Missouri-Kansas City, Kansas City, Missouri bJohn Ochsner Heart and Vascular Institute, Ochsner Clinical School, The University of Queensland School of Medicine, New Orleans cDepartment of Preventive Medicine, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
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van Dam RM, Naidoo N, Landberg R. Dietary flavonoids and the development of type 2 diabetes and cardiovascular diseases: review of recent findings. Curr Opin Lipidol 2013; 24:25-33. [PMID: 23254472 DOI: 10.1097/mol.0b013e32835bcdff] [Citation(s) in RCA: 157] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
PURPOSE OF REVIEW This review summarizes the results on flavonoid intakes and the development of type 2 diabetes and cardiovascular diseases. RECENT FINDINGS Recent advances in food composition databases have allowed the evaluation of a more comprehensive range of flavonoids in epidemiological studies. In addition, the number of randomized trials of flavonoid-rich foods has increased rapidly. Results from both cohort studies and randomized trials suggest that anthocyanidins from berries and flavan-3-ols from green tea and cocoa may lower the risk of type 2 diabetes and cardiovascular diseases. Meta-analyses of randomized trials indicate that the strongest evidence exists for a beneficial effect of green tea on LDL-cholesterol and a beneficial effect of flavan-3-ol-rich cocoa on endothelial function and insulin sensitivity. Few randomized trials had a long duration or evaluated pure flavonoid compounds. SUMMARY Evidence from cohort studies and randomized trials suggest beneficial effects of food sources of anthocyanidins (berries) and flavan-3-ols (green tea and cocoa) on cardiovascular health. These findings need to be confirmed in long-term randomized trials, and evaluation of pure compounds will be important to establish what specific flavonoids and doses are effective.
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Affiliation(s)
- Rob M van Dam
- Saw Swee Hock School of Public Health, National University of Singapore, National University Health System, Singapore, Singapore.
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Beresniak A, Duru G, Berger G, Bremond-Gignac D. Relationships between black tea consumption and key health indicators in the world: an ecological study. BMJ Open 2012; 2:bmjopen-2011-000648. [PMID: 23138107 PMCID: PMC3533110 DOI: 10.1136/bmjopen-2011-000648] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVES The aim of this study was to investigate potential statistical relationships between black tea consumption and key health indicators in the world. The research question is: Does tea consumption is correlated with one or more epidemiological indicators? DESIGN Ecological study using a systematic data-mining approach in which the unit of the analysis is a population of one country. SETTING Six variables, black tea consumption data and prevalence data of respiratory diseases, infectious diseases, cancer, cardiovascular diseases and diabetes, have been studied at a global level. PARTICIPANTS Data from 50 participating countries in the World Health Survey were investigated. PRIMARY AND SECONDARY OUTCOMES MEASURES: Level of statistical relationships between variables. RESULTS Principal component analysis established a very high contribution of the black tea consumption parameter on the third axis (81%). The correlation circle confirmed that the 'black tea' vector was negatively correlated with the diabetes vector and was not correlated with any of the other four health indicators. A linear correlation model then confirmed a significant statistical correlation between high black tea consumption and low diabetes prevalence. CONCLUSIONS This innovative study establishes a linear statistical correlation between high black tea consumption and low diabetes prevalence in the world. These results are consistent with biological and physiological studies conducted on the effect of black tea on diabetes and confirm the results of a previous ecological study in Europe. Further epidemiological research and randomised studies are necessary to investigate the causality.
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Affiliation(s)
- Ariel Beresniak
- Department of Research, Data Mining International, Geneva, Switzerland
| | - Gerard Duru
- Department of Research, Data Mining International, Geneva, Switzerland
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