Tea consumption and bone health in Chinese adults: a population-based study

Nutrition-Based Support for Osteoporosis in Postmenopausal Women: A Review of Recent Evidence

Postmenopausal osteoporosis stands as the predominant bone disorder in the developed world, posing a significant public health challenge. Nutritional factors play a crucial role in bone health and may contribute to its prevention or treatment. Calcium and vitamin D, extensively studied with robust scientific evidence, are integral components of the non-pharmacological treatment for this disorder. Nevertheless, other less-explored nutritional elements appear to influence bone metabolism. This review provides a comprehensive summary of the latest evidence concerning the relationship between various nutrients, such as phosphorus, magnesium, vitamins, phytate, and phytoestrogens; specific foods like dairy or soy, and dietary patterns such as the Mediterranean diet with bone health and osteoporosis.

Sex- and Age-Specific Prevalence of Osteopenia and Osteoporosis: Sampling Survey

BACKGROUND

Osteopenia and osteoporosis are posing a long-term influence on the aging population's health contributing to a higher risk of mortality, loss of autonomy, hospitalization, and huge health system costs and social burden. Therefore, more pertinent data are needed to demonstrate the current state of osteoporosis.

OBJECTIVE

This sampling survey seeks to assess the trends in the prevalence of osteopenia and osteoporosis in a Chinese Han population.

METHODS

A community-based cross-sectional study involving 16,377 participants used a multistage sampling method. Bone mineral density was measured using the quantitative ultrasonic densitometry. Student t test and Mann-Whitney U test were used to test the difference between normally and nonnormally distributed quantitative variables between male and female participants. A chi-square (χ2) test was used to compare categorized variables. Stratified analysis was conducted to describe the prevalence rates of osteoporosis (T score ≤-2.5) and osteopenia (T score -2.5 to -1.0) across age, sex, calcium intake, and menopause. A direct standardization method was used to calculate the age-standardized prevalence rates of osteoporosis and osteopenia. T-score was further categorized into quartiles (T1-T4) by age- and sex-specified groups.

RESULTS

The prevalence rates of osteopenia and osteoporosis were 40.5% (6633/16,377) and 7.93% (1299/16,377), respectively, and the age-standardized prevalence rates were 27.32% (287,877,129.4/1,053,861,940) and 3.51% (36,974,582.3/1,053,861,940), respectively. There was an increase in osteopenia and osteoporosis prevalence from 21.47% (120/559) to 56.23% (754/1341) and 0.89% (5/559) to 17.23% (231/1341), respectively, as age increased from 18 years to 75 years old. The prevalence rates of osteopenia and osteoporosis were significantly higher in female participants (4238/9645, 43.94% and 1130/9645, 11.72%) than in male participants (2395/6732, 35.58% and 169/6732, 2.51%; P<.001), and in postmenopausal female participants (3638/7493, 48.55% and 1053/7493, 14.05%) than in premenopausal female participants (538/2026, 26.55% and 53/2026, 2.62%; P<.001). In addition, female participants with a history of calcium intake had a lower osteoporosis prevalence rate than female participants without any history of calcium intake in all age groups (P=.004). From low quartile to high quartile of T-score, the prevalence of diabetes mellitus (752/4037, 18.63%; 779/4029, 19.33%; 769/3894, 19.75%; and 869/3879, 22.4%) and dyslipidemia (2228/4036, 55.2%; 2304/4027, 57.21%; 2306/3891, 59.26%; and 2379/3878, 61.35%) were linearly increased (P<.001), while the prevalence of cancer (112/4037, 2.77%; 110/4029, 2.73%; 103/3894, 2.65%; and 77/3879, 1.99%) was decreased (P=.03).

CONCLUSIONS

Our data imply that as people age, osteopenia and osteoporosis are more common in females than in males, particularly in postmenopausal females than in premenopausal females, and bone mineral density significantly affects the prevalence of chronic diseases. These findings offer information that can be applied to intervention programs meant to prevent or lessen the burden of osteoporosis in China.

Green tea and hyaluronic acid gel enhance fibroblast activation and improves the gingival healing post-third molar extraction

This study evaluates the effects of a green tea (Camellia sinensis) and hyaluronic acid gel on fibroblast activity and alveolar bone repair following third molar extractions. By examining the gene expression related to cell survival, proliferation, and angiogenesis, the study bridges in vitro findings with clinical outcomes in a split-mouth randomized trial. Human fibroblasts were exposed to the treatment gel, analysing gene expression through RT-qPCR. Twenty participants undergoing bilateral third molar extractions received the test gel on one side and a placebo on the other. Assessments included patient-reported outcomes, professional evaluations, and radiographic analyses at multiple postoperative intervals. The test gel significantly enhanced AKT, CDKs, and VEGF gene expressions, indicating a positive effect on angiogenesis and cell proliferation. Clinically, it resulted in reduced exudate, swelling, and secondary interventions, with radiographs showing improved alveolar bone density after 90 days. The green tea and hyaluronic acid gel significantly improves soft tissue and bone healing post-extraction, offering a promising adjunctive therapy for enhancing postoperative recovery. This gel represents a novel adjuvant treatment option for facilitating improved healing outcomes after third molar extractions, highlighting its potential utility in clinical dental practice.

Tea intake and total body bone mineral density of all ages: a Mendelian randomization analysis

Background

There is increasing evidence indicating that tea intake affects bone mineral density levels; however, the causality between tea intake and bone mineral density is inconclusive. This study aimed to assess the causal relationship between tea intake and total body bone mineral density (TB-BMD) through two-sample Mendelian randomization (MR) analysis.

Methods

We conducted a two-sample MR approach to estimate the potential causal effects of tea intake on TB-BMD at all ages in a European population. The analyses were performed using summary statistics obtained for single-nucleotide polymorphisms (SNPs), identified from a genome-wide association meta-analysis of tea intake (N = up to 447,485 individuals) and from the GEnetic Factors for OSteoporosis (GEFOS) Consortium's genome-wide association meta-analysis (N = up to 56,284 individuals), with baseline data collected in 2018 and populations derived from the European ancestry. The association between each SNP and TB-BMD was weighted by its association with tea intake, and estimates were combined mainly using an inverse-variance weighted meta-analysis. In addition, we explored the potential causal effects between green tea intake, herbal tea intake, and TB-BMD.

Results

The MR analysis revealed that genetically determined tea intake exerts a causal impact on TB-BMD, with an odds ratio (OR) of 1.204 (95% CI: 1.062-1.366, p = 0.004), especially in the age group of 45-60 years (OR = 1.360, 95% CI: 1.088-1.700, p = 0.007). No horizontal pleiotropy and heterogeneity were observed. However, there was no causal effect of tea intake on TB-BMD in the age groups of 0-15, 15-30, 30-45, and over 60 years. In the subgroup analysis, when green tea intake was regarded as the exposure factor, no salient associations were found between green tea consumption and TB-BMD (IVW p = 0.368). Similarly, there was also no causal association between herbal tea intake and TB-BMD (IVW p = 0.264).

Conclusion

The findings of this study support the evidence that tea consumption increases bone density and reduces the risk of osteoporosis in the age group of 45-60 years within the European population.

Potential mechanism of tea for treating osteoporosis, osteoarthritis, and rheumatoid arthritis

Osteoporosis (OP), osteoarthritis (OA), and rheumatoid arthritis (RA) are common bone and joint diseases with a high incidence and long duration. Thus, these conditions can affect the lives of middle-aged and elderly people. Tea drinking is a traditional lifestyle in China, and the long-term intake of tea and its active ingredients is beneficial to human health. However, the mechanisms of action of tea and its active ingredients against OP, OA, and RA are not completely elucidated. This study aimed to assess the therapeutic role and related mechanisms of tea and its active ingredients in OP, OA, and RA. Moreover, it expanded the potential mechanisms of tea efficacy based on network pharmacology and molecular docking. Results showed that tea has potential anti-COX properties and hormone-like effects. Compared with a single component, different tea components synergize or antagonize each other, thereby resulting in a more evident dual effect. In conclusion, tea has great potential in the medical and healthcare fields. Nevertheless, further research on the composition, proportion, and synergistic mechanism of several tea components should be performed.

Tea consumption and risk of bone health: an updated systematic review and meta-analysis

INTRODUCTION

Current research evaluating the association between tea consumption and bone health still has inconsistent findings.

MATERIALS AND METHODS

The electronic databases of Embase, PubMed, Scopus, and Web of Science were systematically searched from inception until December 2022 to identify eligible studies. The calculation of summary relative risks (RRs) and 95% confidence intervals (CIs) was carried out using random-effects models. I2 statistics and Forest plots were used to assess the heterogeneity of RR values across studies.

RESULTS

The pooled relative risks for bone health-related outcomes of interest among tea drinkers, compared to non-drinkers, were 0.910 (95% confidence interval 0.845 to 0.980) for fractures, based on 20 studies, 0.332 (0.207-0.457) for BMD (13 studies), 0.800 (0.674-0.950) for osteoporosis (10 studies), and 1.006 (0.876-1.156) for osteopenia (5 studies). Subgroup analysis of locations showed that the pooled relative risks were 0.903 (0.844-0.966) for the hip, 0.735 (0.586-0.922) for the femur, 0.776 (0.610-0.988) for the lumbar, 0.980 (0.942-1.021) for the forearm and wrist, 0.804 (0.567-1.139) for the phalanges, and 0.612 (0.468-0.800) for Ward's triangle. One-stage dose-response analysis revealed that individuals who consumed less than 4.5 cups of tea per day had a lower risk of bone health-related outcomes than those who did not consume tea, with statistically significant results.

CONCLUSION

There is an association between tea consumption and a reduced risk of fractures, osteoporosis, hip, femur, and lumbar, as well as increased BMD.

Racial/Ethnic Differences in Bone Mineral Density for Osteoporosis

PURPOSE OF REVIEW

We primarily aim to review differences in bone mineral density (BMD) for osteoporosis among different racial/ethnic groups and to highlight the magnitude of racial/ethnic differences in obesity and diabetes. We also explore the factors contributing to the BMD differences among various subgroups. In addition, we investigate the existing disparities in research, educational initiatives, screening practices, and treatment options for osteoporosis and discuss these findings' clinical and public health implications.

RECENT FINDINGS

Racial/ethnic differences in BMD for osteoporosis exist in the USA and other countries. There are disparities regarding osteoporosis screening and treatment. Understanding the factors contributing to these differences can help develop targeted interventions and policies to reduce their impact. Clinicians should consider the racial/ethnic differences in BMD when making treatment decisions and providing preventive care. Future research could contribute to developing effective strategies for preventing osteoporosis among different racial/ethnic groups. This review offered a comprehensive examination of differences in BMD across various racial and ethnic groups, elucidating the influence of genetic, lifestyle, and cultural factors on these differences. This review also highlighted the disparities in osteoporosis screening, treatment options, research on medical effectiveness, and educational outreach tailored to each subgroup. Recognizing the importance of addressing these inequalities, we present this review to advocate for targeted interventions to reduce disparities in osteoporosis and improve bone health for all populations.

Trends of caffeine intake from food and beverage among Chinese adults: 2004-2018

Caffeine is a kind of psychostimulant that naturally exist in foods. The benefits and risks of caffeine depend on the dose. Moreover, the intake of caffeine from dietary sources in China has seldom been assessed. We calculated the dietary caffeine intake of Chinese adult consumers from 2004 to 2018 and analyzed its consumption trends by using data from the China Health and Nutrition Survey and the National Food and Beverage Consumption Survey. Caffeine contents in different dietary items were determined by HPLC. Monte Carlo simulations were applied to estimate caffeine intake. Mann-Kendall trend test and linear regression were used to analyze the trend of caffeine consumption. Among 79,173 individuals, 3972 (5%) of the adult Chinese population consumed caffeine between 2004 and 2018. The average caffeine intake was 123 mg/day for male consumers and 116 mg/day for female consumers. The median and P75 caffeine intake raised over the 14 years. Traditional tea leaves, coffee and sodas are the main sources of caffeine intake. Our findings indicate that most Chinese adults consumed caffeine within the safe level (400 mg/day), but the caffeine consumption has shown an increasing trend in recent 14 years.

Epigallocatechin gallate improves the quality of diabetic oocytes

BACKGROUND

Maternal diabetes compromises the quality and developmental potential of oocytes. Therefore, it is important to study how to ameliorate the adverse effects of diabetes on oocyte quality. Epigallocatechin gallate (EGCG) has a variety of physiological activities, including anti-inflammatory, antioxidant, and anti-diabetes. In the present study, we evaluated the effect of EGCG on the maturation of diabetic oocytes in vitro.

OBJECTIVE

Investigating the role of EGCG in restoring the adverse effects of diabetes on oocyte quality.

METHODS

Diabetes mouse model was established by a single injection of streptozotocin (STZ). Oocytes were collected and matured in vitro with/without EGCG in M16 medium.

RESULTS

Compared with control, diabetic oocytes have a higher frequency of spindle defects and chromosome misalignment, but EGCG effectively reduces the incidence of oocytes with abnormal spindle assembly and chromosome mismatches. Moreover, the abnormal mitochondrial membrane potential (MMP) of diabetic oocytes is significantly alleviated by EGCG, and the reduced expression of genes regulating mitochondrial fusion (Mfn1 and Mfn2) and fission (Drp1) in diabetic oocytes is significantly increased while EGCG is added. EGCG also decreases the higher level of reactive oxygen species (ROS) in diabetic oocytes that may be regulated by the increased expression of superoxide dismutase 1 (Sod1) and superoxide dismutase 2 (Sod2). EGCG can also reduce the DNA damage of diabetic oocytes.

CONCLUSIONS

Our results suggest that EGCG, at least partially, improve the quality of diabetic oocytes.

Frequency of osteoporosis in Chinese patients with rheumatoid arthritis: a meta-analysis

OBJECTIVE

To evaluate the current frequency of osteoporosis (OP) in Chinese patients with rheumatoid arthritis (RA) through meta-analysis.

METHODS

The databases of PubMed, Web of Science, Cochrane Library, CNKI, Wan Fang, CBM, and VIP were searched for relevant literature regarding the occurrence of OP in Chinese patients with RA from January 1, 2000, to September 15, 2022. The literature was screened using inclusion and exclusion criteria, and qualifying articles were subjected to data extraction, quality evaluation, and meta-analysis using Stata 17.0 software.

RESULTS

Altogether, 44 publications were included in this study, with a total sample size of 12,264 RA cases and 4532 patients with OP. Meta-analysis revealed that the frequency of OP in patients with RA was 37.67% [95% CI: 34.38%, 40.97%], while subgroup analysis showed that the frequency in South China was 49.43% [95% CI: 40.53%, 58.32%]. Also, the frequency in men was 29.29% [95% CI: 22.42%, 36.16%], which was significantly lower than in women (41.89% [95% CI: 36.87%, 46.90%]). The incidence rate in pre-menopausal women was only 15.19% [95% CI: 8.79%, 21.59%], much lower than the figure of 54.29% [95% CI: 45.28%, 63.30%] for post-menopausal women. Additionally, the frequency rates in the low, intermediate, and high disease activity groups were 24.52% [95% CI: 11.52%, 37.52%)], 27.67% [95% CI: 13.50%, 41.85%], and 57.96% [95% CI: 37.35%, 78.56%], respectively.

CONCLUSION

The frequency of OP in the Chinese RA population is higher than the world average, and patients with RA should receive standardized anti-RA therapy at an early stage, with emphasis on bone health in postmenopausal women, patients with high disease activity or longer disease duration.

Tea consumption and the risks of osteoporosis and hip fracture: a population-based longitudinal follow-up study

This population-based longitudinal follow-up study showed a protective effect of tea consumption against osteoporosis, particularly among women and middle-aged people. High tea consumption was also associated with a reduced risk of hip fracture.

INTRODUCTION

To investigate the association of tea consumption with the risks of osteoporosis and hip fracture.

METHODS

This study used the Keelung Community-based Integrated Screening database and Taiwan's National Health Insurance Research Database. A total of 42,742 subjects aged 45 to 74 years were enrolled. Each was classified as no tea consumption, low tea consumption, and high tea consumption, according to the results of an eating habits questionnaire. The diagnosis of osteoporosis and hip fracture was based on BMD measured by dual-energy X-ray absorptiometry and the X-ray findings. The median follow-up time was 8.5 years.

RESULTS

As compared with the no tea consumption group, the osteoporosis HRs for the low tea consumption and high tea consumption groups were 0.88 (95% confidence interval (CI) 0.80-0.96) and 0.87 (95% CI 0.80-0.94), respectively. Among those participants aged 59 or below, the osteoporosis HRs for low tea consumption and high tea consumption (vs. no tea consumption) were 0.85 (95% CI 0.74-0.96) and 0.79 (95% CI 0.69-0.90). The HRs of hip fracture for the low tea consumption and high tea consumption groups (vs. no tea consumption) were 0.85 (95% CI 0.67-1.08) and 0.69 (95% CI 0.55-0.86), respectively.

CONCLUSION

Tea consumption was linked to a lower risk of osteoporosis, particularly among women and middle-aged people. High tea consumption was also associated with a reduced risk of hip fracture.

Non-fermented tea consumption protects against osteoporosis among Chinese male elders using the Taiwan biobank database

Few studies compared the effects of non-fermented and fermented tea among the general population. We aimed to compare the risk of incident osteoporosis (OP) between non-fermented tea and fermented tea drinkers by this retrospective nationwide population-based analysis from the Taiwan Biobank. Participants ≥ 40 years who drink fermented tea (n = 2205) were compared with those who drink non-fermented tea (n = 1034) from 2008 to 2015 with a mean follow-up period of 3.64 years. OP was defined by T-score ≤ − 2.5. Multivariate Cox proportional hazards regression models were performed to estimate the risk of developing OP between the two groups. Separate models were used to determine the relationship between tea consumption and OP stratified by sex and age. There was a significant interaction between sex, age, and type of tea consumed. In men aged ≥ 60 years, the risk of developing OP decreased by 79% for those who drank non-fermented tea (hazard ratio, 0.21; 95% confidence level, 0.05–0.94) than those who drank fermented tea. Additionally, those with a family history of OP had a higher risk of developing osteoporosis. This study suggests that male elderly who consume non-fermented tea have a lower risk of OP. Drinking non-fermented tea, such as green tea, could be suggested, especially for those with a family history of osteoporosis.

Innovative Application of Chicken Eggshell Calcium to Improve the Functional Value of Gingerbread

Food waste, such as eggshell, can be an environmental problem if it is not properly managed. One of the ways to solve this is by using the eggshell as the cheap calcium source in food products. Polish gingerbread fortified with chicken eggshell powder (ESP) calcium was developed to solve the eggshell waste problem and to reduce the risk of osteoporosis. This study focused on the effect of ESP addition on basic composition, sensory evaluation, and antioxidative activity of gingerbread. Two samples of gingerbread without and with 3% (w/w of wheat flour) ESP, with controlled green tea powder (4% w/w of white chocolate) were analyzed. Results of the research showed that the addition of 3% ESP significantly increased the ash and calcium content (p < 0.05) without changing the appearance, aroma, texture, taste profiles, and the hedonic score of gingerbread. The gingerbread samples were then stored for 2 months and were analyzed every month. The hedonic evaluation of the aroma of both gingerbread samples decreased significantly (p < 0.05) during storage. During 2 months of storage, the antioxidative activity of gingerbread fortified with 3% ESP was not significantly different compared to the control (p > 0.05), particularly in ABTS and ORACFL assay. The ABTS, DPPH, and ORACFL assays showed decreasing antioxidative activity during storage, which was also in accordance with decreasing total phenolic content of both gingerbread samples. In PCL assay, the lipid-soluble antioxidant activity in gingerbread with 3% ESP was significantly higher during 2 months of storage, compared to the control (p < 0.05). The developed product might be a potential alternative to improve the calcium (26% daily value (DV) recommendation per 100 g) and antioxidant intake in order to prevent calcium deficiency. Gingerbread enriched with an organic source of calcium may become an innovative product to reduce the risk of developing osteoporosis in the elderly population, having potential health and economic significance, given the incidence of osteoporosis and the costs of treating this disease.

Increased dosage and treatment time of Epigallocatechin-3-gallate (EGCG) negatively affects skeletal parameters in normal mice and Down syndrome mouse models

Bone abnormalities affect all individuals with Down syndrome (DS) and are linked to abnormal expression of DYRK1A, a gene found in three copies in people with DS and Ts65Dn DS model mice. Previous work in Ts65Dn male mice demonstrated that both genetic normalization of Dyrk1a and treatment with ~9 mg/kg/day Epigallocatechin-3-gallate (EGCG), the main polyphenol found in green tea and putative DYRK1A inhibitor, improved some skeletal deficits. Because EGCG treatment improved mostly trabecular skeletal deficits, we hypothesized that increasing EGCG treatment dosage and length of administration would positively affect both trabecular and cortical bone in Ts65Dn mice. Treatment of individuals with DS with green tea extract (GTE) containing EGCG also showed some weight loss in individuals with DS, and we hypothesized that weights would be affected in Ts65Dn mice after EGCG treatment. Treatment with ~20 mg/kg/day EGCG for seven weeks showed no improvements in male Ts65Dn trabecular bone and only limited improvements in cortical measures. Comparing skeletal analyses after ~20mg/kg/day EGCG treatment with previously published treatments with ~9, 50, and 200 mg/kg/day EGCG showed that increased dosage and treatment time increased cortical structural deficits leading to weaker appendicular bones in male mice. Weight was not affected by treatment in mice, except for those given a high dose of EGCG by oral gavage. These data indicate that high doses of EGCG, similar to those reported in some treatment studies of DS and other disorders, may impair long bone structure and strength. Skeletal phenotypes should be monitored when high doses of EGCG are administered therapeutically.

Relationship between Regular Green Tea Intake and Osteoporosis in Korean Postmenopausal Women: A Nationwide Study

Mixed results have been reported regarding whether habitual tea intake affects bone health. This study investigated the relationship between green tea intake and bone mineral density (BMD) in postmenopausal Korean women. We used data from the Korean National Health and Nutrition Examination Surveys from 2008 to 2011 and divided the participants into three groups according to their frequency of green tea intake over the past 12 months. BMD of the lumbar spine, total femur, and femur neck was measured using dual-energy X-ray absorptiometry. The odds ratios (ORs) and 95% confidence intervals (CIs) of osteoporosis and osteopenia according to green tea consumption were analyzed. Participants who did not consume green tea or consumed less than one cup per day were more likely to have osteopenia of the lumbar spine or femur than those who consumed it once to three times a day (OR 1.81 and 1.85, 95% CI, 1.20–2.71; and 1.23–2.77). Moreover, ORs for osteoporosis were 1.91 (95% CI 1.13–3.23) and 1.82 (95% CI 1.09–3.05) in non-consumers and consumers who drank less than one cup per day, respectively, compared with the reference group. These results support that green tea consumption may have benefits on bone health.

The relationship between healthy lifestyles and bone health: A narrative review

BACKGROUND

Bone health, especially osteoporosis among ageing populations, has become an important topic for both clinical and basic researchers. The relationship between bone health and healthy lifestyles has been frequently discussed. The present study focuses on the relationship between bone health and healthy lifestyles among older adults, based on a global comparison.

METHODS

This narrative review was performed by collecting clinical trials, basic research and reviews on lifestyle and bone health in PubMed database.

RESULTS

Positive effects of physical activity and negative effects of malnutrition, alcohol abuse, and cigarette smoking on bone health were revealed. The relationship between bone health and drinking coffee and tea is still inconclusive. Moreover, the diversity of each region should be aware when considering healthy lifestyles to improve bone health.

CONCLUSION

Healthy lifestyles are highly related to bone health, and different lifestyles may have different influences on regions with a high risk of bone diseases. It is practical to acknowledge the diversity of economic, religious, environmental and geological conditions in each region when providing suitable and effective recommendations for healthy lifestyles that can improve overall bone health.

Does Drinking Coffee and Tea Affect Bone Metabolism in Patients with Inflammatory Bowel Diseases?

Patients suffering from Crohn’s disease and ulcerative colitis are at higher risk of osteoporosis due to lower bone mineral density. Risk factors of osteoporosis are divided into unmodifiable, namely, age, gender, genetic factors, as well as modifiable, including diet, level of physical activity, and the use of stimulants. Coffee and tea contain numerous compounds affecting bone metabolism. Certain substances such as antioxidants may protect bones; other substances may increase bone resorption. Nevertheless, the influence of coffee and tea on the development and course of inflammatory bowel diseases is contradictory.

Multi-mycotoxin contamination of green tea infusion and dietary exposure assessment in Moroccan population

Green tea infusion is one of the most widely drunk beverages worldwide due to its health benefits associated with microelements, essential oils, and polyphenols, etc. Several studies have reported that green tea is subjected to contamination by various toxigenic fungi. Thus, this work aims to investigate the co-occurrence of 15 mycotoxins [four aflatoxins (AFB1, AFB2, AFG1, AFG2), ochratoxin A (OTA), beauvericin (BEA), four enniatins (ENA, ENA1, ENB, ENB1), zearalenone (ZEN), alternariol (AOH), tentoxin (TENT), T-2 and HT-2 toxins] in green tea samples available in Morocco by liquid chromatography tandem mass spectrometry method. Analytical and consumption data were then used to assess the dietary exposure for the population. Out of 111 total green tea samples, 62 (56%) were contaminated by at least one mycotoxin. The most found mycotoxins in samples were AOH (40%), ZEN (35%), AFG1 (2%), AFB2 (2%), ENB (2%) and TENT (1%). The highest level was found for ZEN with 45.8 ng/g. There is no sample that exceeded the recommended levels set by European Pharmacopoeia for certain mycotoxins in plant material. Although multi-mycotoxin co-occurred in samples (33%), the probable estimated daily intake values show that the intake of mycotoxins through the consumption of green tea does not represent a risk for the population.

Osteoprotective Roles of Green Tea Catechins

Osteoporosis is the second most common disease only secondary to cardiovascular disease, with the risk of fracture increasing with age. Osteoporosis is caused by an imbalance between osteoblastogenesis and osteoclastogenesis processes. Osteoclastogenesis may be enhanced, osteoblastogenesis may be reduced, or both may be evident. Inflammation and high reactive oxygen enhance osteoclastogenesis while reducing osteoblastogenesis by inducing osteoblast apoptosis and suppressing osteoblastic proliferation and differentiation. Catechins, the main polyphenols found in green tea with potent anti-oxidant and anti-inflammatory properties, can counteract the deleterious effects of the imbalance of osteoblastogenesis and osteoclastogenesis caused by osteoporosis. Green tea catechins can attenuate osteoclastogenesis by enhancing apoptosis of osteoclasts, hampering osteoclastogenesis, and prohibiting bone resorption in vitro. Catechin effects can be directly exerted on pre-osteoclasts/osteoclasts or indirectly exerted via the modulation of mesenchymal stem cells (MSCs)/stromal cell regulation of pre-osteoclasts through activation of the nuclear factor kB (RANK)/RANK ligand (RANKL)/osteoprotegerin (OPG) system. Catechins also can enhance osteoblastogenesis by enhancing osteogenic differentiation of MSCs and increasing osteoblastic survival, proliferation, differentiation, and mineralization. The in vitro effects of catechins on osteogenesis have been confirmed in several animal models, as well as in epidemiological observational studies on human subjects. Even though randomized control trials have not shown that catechins provide anti-fracture efficacy, safety data in the trials are promising. A large-scale, placebo-controlled, long-term randomized trial with a tea regimen intervention of optimal duration is required to determine anti-fracture efficacy.

Differences in fracture prevalence and in bone mineral density between Chinese and White Canadians: the Canadian Multicentre Osteoporosis Study (CaMos)

Fracture determinants differ between Canadians of Chinese and White descent, the former constituting the second largest visible minority group in Canada. The results of this study support the importance of characterizing bone health predictors in Canadians of different ethnicity to improve population-specific fracture prevention and treatment strategies.

PURPOSE

We aimed to compare clinical risk factors, bone mineral density, prevalence of osteoporosis, and fractures between Chinese and White Canadians to identify ethnicity-specific risks.

METHODS

We studied 236 Chinese and 8945 White Canadians aged 25+ years from the Canadian Multicentre Osteoporosis Study (CaMos). The prevalence of osteoporosis using ethnicity-specific peak bone mass (PBM), and of prior and incident low trauma fractures were assessed and compared between groups. Linear regressions, adjusting for age and anthropometric measures, were used to examine the association between baseline and 5-year changes in BMD and ethnicity.

RESULTS

Chinese participants had shorter stature, lower BMI, and lower rate of falls than White participants. Adjusted models showed no significant differences in baseline BMD between ethnic groups except in younger men where total hip BMD was 0.059 g/cm² (0.009; 0.108) lower in Chinese. Adjusted 5-year BMD change at lumbar spine was higher in older Chinese women and men compared with Whites. When using Chinese-specific PBM, the prevalence of osteoporosis in Chinese women was 2-fold lower than when using that of White women The prevalence of fractures was higher in White women compared with Chinese with differences up to 14.5% (95% CI 9.2; 19.7) and 10.5% (95% CI 4.5-16.4) in older White men. Incident fractures were rare in young Chinese compared with White participants and not different in the older groups.

CONCLUSION

Our results support the importance of characterizing bone strength predictors in Chinese Canadians and the development of ethnicity-specific fracture prediction and prevention strategies.

Long-term exposure to air pollution might increase prevalence of osteoporosis in Chinese rural population

OBJECTIVES

The associations of long-term exposure to air pollution with osteoporosis are rarely reported, especially in rural China. This study aimed to explore the association among rural Chinese population.

METHODS

A total of 8033 participants (18-79 years) derived from the Henan Rural Cohort Study (n = 39,259) were included in this cross-sectional study. Exposure to air pollutants was estimated using machine learning algorithms with satellite remote sensing, land use information, and meteorological data [including particulate matter with aerodynamic diameters ≤1.0 μm (PM₁), ≤2.5 μm (PM_2.5), and ≤10 μm (PM₁₀), and nitrogen dioxide (NO₂)]. The bone mineral density of each individual was measured by using ultrasonic bone density apparatus and osteoporosis was defined based on the T-score ≤ -2.5. Multiple logistic regression models were used to examine the association of air pollution and osteoporosis prevalence.

RESULTS

We observed that per 1 μg/m³ increase in PM₁, PM_2.5, PM₁₀ and NO₂ were associated with a 14.9%, 14.6%, 7.3%, and 16.5% elevated risk of osteoporosis. Compared with individuals in the first quartile, individuals in the fourth quartile had higher odds ratio (OR) of osteoporosis (P-trend < 0.001), the ORs (95% confidence interval) were 2.08 (1.72, 2.50) for PM₁, 2.28 (1.90, 2.74) for PM_2.5, 1.93 (1.60, 2.32) for PM₁₀, and 2.02 (1.68, 2.41) for NO₂. It was estimated that 20.29%-24.36% of osteoporosis cases could be attributable to air pollution in the rural population from China.

CONCLUSIONS

Long-term exposure to air pollutants were positively associated with high-risk of osteoporosis, indicated that improving air quality may be beneficial to improve rural residents health.

Black Tea Exhibits a Dose-Dependent Response in Saos-2 Cell Mineralization

Higher bone mineral density (BMD) is often associated with greater consumption of black tea (BT). However, the dose–response of BT on mineralization in an osteoblast cell model has not yet been studied. The study objective was to determine the dose-dependent response of BT in Saos-2 cells and investigate changes to several proteins involved in the mineralization process. Mineralization was induced in the presence of BT at concentrations that represent levels likely achieved through daily consumption (0.1, 0.5, 0.75, 1 μg gallic acid equivalents [GAE]/mL) or through supplementation (2, 5, or 10 μg GAE/mL). BT exerted a positive dose–response on bone mineralization, peaking at 1 μg GAE/mL of BT (P < .05). Cellular activity was significantly greater than control with exposure to 2–10 μg GAE/mL of BT (at 24 h) (P < .05) and 1–10 μg GAE/mL (at 48 h) (P < .05), with a peak at 5 μg GAE/mL at 24 and 48 h (P < .05). Protein expression of alkaline phosphatase and ectonucleotide pyrophosphatase/phosphodiesterase-1 were unchanged, whereas a moderate dose of BT (0.75 μg GAE/mL) resulted in greater expression of osteopontin compared with the highest dose (10 μg GAE/mL) (P < .05). Doses of BT from 0.5 to 10 μg GAE/mL resulted in higher antioxidant capacity compared with control (P < .05). In summary, the higher antioxidant capacity, enhanced cell viability, and upregulated mineralization suggest that consumption of BT may have a positive effect on BMD at levels obtained through consumption of tea.

Oolong tea drinking boosts calcaneus bone mineral density in postmenopausal women: a population-based study in southern China

INTRODUCTION

Observational studies have shown that tea consumption has a potentially beneficial effect on bone health. However, few studies have assessed the effects of types of tea consumed on bone health. We aimed to investigate whether drinking oolong tea is associated with increased calcaneus bone mineral density (BMD) in postmenopausal women.

METHODS

From an epidemiological survey in Shantou, 476 postmenopausal women aged 40 to 88 years were enrolled in the study. All women were questioned about their demographic features, lifestyle, health status, types of tea consumed, habit of tea consumption, and habitual dietary intake by use of a structured questionnaire. Estimated areal BMD was measured by calcaneal quantitative ultrasound (QUS).

RESULTS

As compared with non-tea drinkers, oolong tea drinkers had higher calcaneus BMD (β 34.70 [95% CI 10.38, 59.03]). In addition, calcaneus BMD was significantly increased for those drinking 1-5 cups/day (β 27.43 [95% CI 3.70, 51.16]) but not > 5 cups/day. We observed no linear increase in calcaneus BMD with increasing years of tea consumption and local polynomial regression fitting showed a parabola-shaped association between years of tea consumption and calcaneus BMD. However, symptoms of osteoporosis did not differ by types of tea consumed.

CONCLUSION

Long-term moderate oolong tea consumption may have beneficial effects on bone health in postmenopausal women in Shantou of southern China.

Components identification and nutritional value exploration of tea (Camellia sinensis L.) flower extract: Evidence for functional food

Camellia sinensis L., its fresh leaves and buds are used to make tea, is an important industrial crop with a long history. However, less attention has been paid to tea flowers. Indeed, tea flower extract (TFE) is a rich source of functional molecules, but its nutritional value remains unclear. This study, from the perspective of "whole food", aimed to investigate the composition of TFE and further explore its possible health-promoting effects on cyclophosphamide-induced mice. It was found that TFE was mainly composed of carbohydrates (34.02 ± 1.42%), phenolic compounds (11.57 ± 0.14%), crude proteins (27.72 ± 3.07%) and saponins (2.81 ± 0.00%). Supplementation of TFE at 200 mg/kg·BW/d regulated intestinal homeostasis by improving the intestinal barrier, alleviating dysbacteriosis (reverse 44 of 68 disordered genera), stimulated immunoreactions with significant enhancement of serum TNF-α, IFN-γ, IL-1β, IL-2 and IL-6. Furthermore, TFE could improve the liver function through decreasing the hepatic malondialdehyde and aminotransferase levels and increasing the levels of catalase, myeloperoxidase, superoxide dismutase and reduced glutathione. Notably, the ameliorating effects of TFE on cyclophosphamide-induced immunosuppression and the hepatic injury were associated with its modulation of gut microbiota. The results provide the evidence for the application of tea flower as potential functional food.

Gender-specific prevalence and influencing factors of osteopenia and osteoporosis in Chinese rural population: the Henan Rural Cohort Study

OBJECTIVE

The aims of this study were to describe distributions of the prevalence of osteopenia and osteoporosis and identify the potential risk factors by gender in a Chinese rural population.

DESIGN

A cross-sectional survey.

SETTING AND PARTICIPANTS

A total of 8475 participants (18-79 years) were obtained from the Henan Rural Cohort Study. Bone mineral density (BMD) of the calcaneus for each individual was measured by ultrasonic bone density apparatus. Logistic regression models were used to evaluate associations of potential risk factors with prevalence of osteopenia and osteoporosis. Furthermore, a meta-analysis of prevalence of osteoporosis which included eight studies was conducted to confirm this study results.

RESULTS

The mean of BMD were 0.42 and 0.32 g/cm² for men with osteopenia and osteoporosis (p<0.001), as well as 0.40 and 0.30 g/cm² (p<0.001) for women with osteopenia and osteoporosis, respectively. The overall age-standardised prevalence of osteopenia and osteoporosis were 42.09% and 11.76% in all participants. The age-standardised prevalence of osteopenia in men (45.98%) was significantly higher than that in women (39.73%), whereas the age-standardised prevalence of osteoporosis in men (7.82%) was lower than that in women (14.38%). Meta-analysis results displayed pooled prevalence of osteoporosis of 18.0% (10.1%-25.8%) in total sample, 7.7% (5.7%-9.7%) in men and 22.4% (17.1%-27.6%) in women. Multivariable logistic regression models showed that ageing, women, low education level or income, drinking or underweight was related to increased risk for osteopenia or osteoporosis.

CONCLUSIONS

About one-sixth of the participants suffered osteoporosis in rural China, and the prevalence in women was higher than men. Although the results were lower than that of meta-analysis, osteoporosis still accounts for huge burden of disease in rural population due to limited medical service and lack of health risk awareness rather than urban area.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry (ChiCTR-OOC-15006699; Pre-results).

Lipid profiles as potential mediators linking body mass index to osteoporosis among Chinese adults: the Henan Rural Cohort Study

This study is to examine the relationship between body mass index (BMI) and osteoporosis in rural areas of China, and then explore whether this association was mediated by lipid profiles. Results showed that with the increasing of BMI, the risk of osteoporosis was reduced, and lipid profiles mediate this association.

INTRODUCTION

To examine the relationship between BMI and osteoporosis, and explore whether this association was mediated by lipid profiles.

METHODS

A total of 8272 participants (18-79 years) were enrolled from the Henan Rural Cohort Study. The bone mineral density of the calcaneus was measured using an ultrasonic bone density apparatus. Logistic regression and restricted cubic splines were used to evaluate the odds ratio (OR) and 95% confidence intervals (95% CI). Mediation analysis using bootstrap was performed to examine the contribution of lipid profiles to BMI-related osteoporosis.

RESULTS

The crude and age-standardized prevalence of osteoporosis were 15.93% and 11.77%, respectively. The mean BMIs were 24.12 kg/m² for participants with osteoporosis and 25.06 kg/m² for non-osteoporosis participants (P < 0.001). After adjusting for potential confounders, subjects with obesity had a lower OR of osteoporosis (0.493 [95% CI: 0.405-0.600], P_trend < 0.001) compared with normal-weight individuals. Mediation analysis showed that lipid profile partly mediated the relationship between BMI and osteoporosis with indirect effect OR (95% CI) of 0.985 (0.978-0.992), and the proportion explained of BMI was 15.48% for lipid profile.

CONCLUSION

With the increasing of BMI, the risk of osteoporosis was reduced in the Chinese adult population, and lipid profiles may be a potential mediator linking reduced risk of osteoporosis. Elucidating the underlying mechanisms will facilitate developing feasible preventive and therapeutic measures for osteoporosis. Chinese clinical trial register: ChiCTR-OOC-15006699.