Dietary total antioxidant capacity and the occurrence of metabolic syndrome and its components after a 3-year follow-up in adults: Tehran Lipid and Glucose Study

Association between the oxidative balance score with metabolic syndrome traits in US adults

OBJECTIVE

To explore the association between the Oxidative Balance Score (OBS), which represents the balance of multiple oxidative stress-related dietary and lifestyle exposures, and the risk of metabolic syndrome (MetS).

METHODS

A population-based cross-sectional study design was adopted and 16,850 participants in NHANES database were included in the statistics analysis stage. The OBS was constructed by combining information from 20 a priori selected pro- and antioxidant factors. Weighted logistic regression and restricted cubic splines (RCS) were used to estimate the association between OBS and MetS.

RESULTS

Participants in the highest OBS quartile, indicating low oxidative stress (OS) levels, exhibited a significantly lower risk of MetS (odds Ratio [OR] = 0.55, 95% confidence Interval [CI]: 0.47-0.64) compared to the lowest quartile. Specifically, higher OBS was inversely associated with abdominal obesity (OR = 0.61, 95% CI: 0.54-0.69), hypertension (OR = 0.69, 95% CI: 0.58-0.83), elevated triglycerides (OR = 0.68, 95% CI: 0.57-0.82), low high-density lipoprotein cholesterol (HDL-C) levels (OR = 0.60, 95% CI: 0.50-0.70) and fasting blood glucose (FBG) levels (OR = 0.74, 95% CI: 0.62-0.88). The observed inverse association between OBS and hypertension or FBG levels appeared to primarily influenced by BMI. The association between dietary OBS intervals and elevated FBG levels was not statistically significant in men, whereas the risk was lower by 25% in women.

CONCLUSIONS

A higher OBS, representing a balance of multiple oxidative stress-related dietary and lifestyle exposures, is associated with a lower risk of MetS. Therefore, adhering to an antioxidant diet and lifestyle may help prevent the occurrence of metabolic disorders.

Dietary total antioxidant capacity in relation to disease severity and risk of mortality in cirrhosis; results from a cohort study

Liver Cirrhosis, defined as the final stage of chronic liver disease, may become more prevalent in the lower level of body defense against oxidation and inflammation. Therefore, we assessed the association of dietary total antioxidant capacity (DTAC) with the severity and mortality of cirrhosis in a cohort study. 120 newly diagnosed cirrhosis patients from Tehran, Iran, participated in this study. The patients' habitual diet was assessed using a 168-item validated food frequency questionnaire. Both ferric-reducing antioxidant potential (FRAP) and oxygen radical scavenging capacity (ORAC) methods were computed to achieve DTAC scores. The association between DTAC with disease severity and mortality was estimated by multivariate linear regression and cox proportional hazards regression models. Dietary total antioxidant capacity-ORAC had a significant inverse association with disease severity in both crude and adjusted models (P for trend: <0.001 and 0.016 respectively). The risk of mortality in the first and second tertiles of ORAC was 5.56 (95 % CI: 2.25-13.75; P = 0.002) and 3.20 (95 % CI: 1.25-8.19; P = 0.015) higher than those in the third category, respectively. In conclusion, a higher antioxidant capacity of diet is associated with less disease severity and mortality risk in cirrhosis.

Association between dietary antioxidant indices and hypertension among Chinese adults

The effect of dietary antioxidants on blood pressure (BP) regulation and hypertension risk remains largely unknown. This study aimed to comprehensively assess the impacts of dietary antioxidants on systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and pulse pressure (PP), and hypertension risk among Chinese adults. The cross-sectional study assessed data from 12,046 Chinese adults, evaluating dietary antioxidant quality scores (DAQS) and total antioxidant capacity (DTAC) via a validated food frequency questionnaire. MAP was derived using the formula DBP + (0.412 ×PP), with PP calculated as SBP - DBP. The relationship between DAQS, DTAC, and hypertension prevalence was analyzed using multivariable logistic regression. Among participants not taking antihypertensive medications, those in the highest groups of DTAC and DAQS had significantly lower SBP, DBP, MAP, and PP compared to those in the lowest groups (all p-trends <0.001). Relative to the lowest quintile (Q1) of DTAC (adjusted odds ratios (OR) for hypertension decreased in Q2 (OR 0.90, 95%CI 0.79-1.03), Q3 (OR 0.65, 95% CI 0.56-0.76), Q4 (OR 0.51, 95% CI 0.43-0.60), and Q5 (OR 0.38, 95% CI 0.31-0.46) (p trend <0.001). For DQAS, hypertension OR of category 5 was 0.38 (95% CI 0.32-0.46) compared to that of category 1. Increased vitamin A, Zinc, and selenium intake correlated with reduced hypertension risk. A significant non-linear DTAC and linear DAQS relationships were observed and hypertension risk. Antioxidant-rich diets markedly lowered SBP, DBP, MAP, PP, and hypertension risk.

Association of dietary total antioxidant capacity with general and abdominal obesity in type 2 diabetes mellitus patients

BACKGROUND

The dual existence of Type 2 Diabetes Mellitus (T2DM) and obesity within a single individual may describe a combined adverse health effects, including impaired quality of life and increased risk for cardiovascular diseases (CVDs). Oxidative stress is a contributing factor to the pathogenesis of obesity. Meanwhile, dietary antioxidants may improve the antioxidant defense system and thereby decrease oxidative injury. Dietary total antioxidant capacity (TAC) is usually used to investigate the potential health effects of dietary antioxidant intake on several oxidative stress induced chronic diseases. This study aimed to examine the association of dietary TAC with obesity-related features in T2DM patients.

METHODS

The present study included 254 type 2 diabetes outpatients with a mean (SD) age of 54.52 (7.21) years and mean (SD) diabetes duration of 8.2 (6.4) years. Data on dietary intake was assessed using a validated food frequency questionnaire. Dietary TAC was estimated by ferric reducing antioxidant potential (FRAP) method. Anthropometric, clinical and lifestyle characteristics were all collected.

RESULTS

In linear regression analyses, dietary antioxidant capacity was inversely associated with body mass index (β = -0,231; 95% CI, -0,419 to -0,042), waist circumference (β = -0,427; 95% CI, -0,849 to -0,006) and fat mass percentage (β = -0,328; 95% CI, -0,545 to -0,112) independently of the assessed confounding variables. Interestingly, dietary TAC showed positive and significant associations with vitamin A, vitamin C, β-carotene, magnesium, folic acid and iron intakes, after adjusting for age and daily energy intake.

CONCLUSIONS

Higher intake of dietary TAC was in association with lower indices of general and central obesity in T2DM patients. Therefore, dietary recommendations for counteracting obesity in patients with T2DM should take into account a high dietary TAC.

Composite dietary antioxidant index is associated with reduced prevalence of metabolic syndrome but not mortality in metabolic syndrome: Results from NHANES 2001-2018

The relationship between the composite dietary antioxidant index (CDAI), a comprehensive measure of individual dietary antioxidants, and the prevalence and mortality of metabolic syndrome (MetS) remains unknown. We aimed to explore these relationships in the National Health and Nutrition Examination Survey (NHANES). We explored these relationships using two independent cohorts. First, we addressed CDAI and the prevalence of MetS in the general population; second, we explored the association between CDAI and mortality in patients with MetS by following NHANES 2001-2018 participants through December 31, 2019. In addition, restricted cubic spline (RCS), stratified analysis, and sensitivity analysis were used for further interpretation. We included 24,514 participants aged 20-85 years, in which the prevalence of MetS was 27.61 %. CDAI was negatively and dose-responsively associated with the prevalence of MetS, however it was not associated with mortality in patients with MetS. In addition, CDAI was associated with a reduced prevalence of certain components of MetS, including dyslipidemia and central obesity. RCS showed a linear correlation between CDAI and MetS and the above components. Stratified analyses indicated that alcohol consumption was a significant influence of CDAI-MetS and that socioeconomic status and lifestyle specificity existed. Sensitivity analysis confirmed the stability of the results. CDAI was protective against the development of MetS in the general population, but not against mortality in patients with MetS. Clinicians need to develop individualized prevention strategies to reduce the development of MetS by modifying CDAI.

The association between dietary anti-oxidant quality score and psychological disorders among Iranian adults: a population-based study

OBJECTIVE

Evidence linking relation between dietary antioxidant quality score (DAQS) and psychological disorders is limited. Therefore, this study aimed to assess relationship between DAQSs and psychological disorders including depression, anxiety and stress among Iranian adults.

METHODS

This cross-sectional study used data on 7165 participants of the recruitment phase of Yazd Health Study (YaHS) and Taghzieh Mardom-e-Yazd Study (TAMYZ). Dietary intakes and psychological problems were evaluated using a validated semi-quantitative food frequency questionnaire and the validated Iranian version of depression, anxiety and stress scale questionnaire. DAQS was calculated for each person by summing up the assigned scores to a ratio between daily consuming each of the nutrients including vitamin A, C, E, selenium, manganese, zinc and their daily recommended intake (Score of 0 for a ratio of <2/3 and 1 for a ratio of >2/3). Eventually, association between DAQS and psychological disorders was assessed via logistic regression analysis.

RESULTS

Although no significant relationship was observed between DAQS and psychological disorders in general population, a protective role was found for DAQS against anxiety only in women after adjusting history of chronic disease; age; marital status; education level; smoking status; total energy intake and physical activity level (second tertile versus first tertile: OR: 0.63, 95% CI: 0.40-0.99). However, this finding was nonsignificant after further adjustment for body mass index.

CONCLUSION

Average levels of DAQS might be related to psychological distress especially among women. However, more studies are recommended to valid the findings.

Association of dietary total antioxidant capacity, alternative healthy eating index, and dietary inflammatory index with semen quality in men seeking infertility treatment

Background

Since the association between dietary quality scores and semen quality remains unclear, we carried out a hospital-based cross-sectional study to investigate the association of Dietary Total Antioxidant Capacity (dTAC), Dietary Inflammatory Index (DII), and Alternative Healthy Eating Index (AHEI) scores with semen quality in men seeking infertility treatment.

Methods

This study enrolled 210 men with unexplained or idiopathic infertility. Semen samples were collected and analyzed according to the WHO 2010 criteria. Dietary data was collected using a 168-item semi-quantitative food frequency questionnaire (FFQ) developed for Tehran Lipid and Glucose Study. Multivariable logistic regression models were used to estimate the relationship between dTAC, AHEI, and DII scores with abnormal semen in crude and adjusted models.

Results

There were no significant differences across quartile categories of the dTAC, AHEI, and DII scores regarding semen parameters. There was a trend toward a significant direct association between DII and abnormal semen risk (p = 0.01). Infertile men in the highest quartile of DII had a 2.84 times higher risk of abnormal semen in the crude model (OR: 3.84; 95% CI: 1.64-8.95); such that remained after adjusting for several potential confounders. There was no significant association between dTAC or AHEI and the risk of abnormal semen in infertile men, either before or after adjusting for potential confounders. Total energy (p = 0.05), fat (p = 0.02), saturated fat (p = 0.02), mono-saturated fat (p = 0.009), Thiamine (Vitamin B1) (p = 0.02), Niacin (Vitamin B3) (p = 0.03), Calcium (p = 0.01), and Selenium (p = 0.01) were inversely associated with semen normality.

Discussion

The study suggests that certain dietary factors may affect semen quality, and the mechanisms underlying the observed associations are likely multifactorial, involving complex interactions between diet, oxidative stress, inflammation, and hormone levels. Further research is required to confirm the results, fully elucidate the mechanisms underlying the associations, and identify specific dietary interventions that may improve male fertility outcomes.

Associations of cumulative average dietary total antioxidant capacity and intake of antioxidants with metabolic syndrome risk in Korean adults aged 40 years and older: a prospective cohort study (KoGES_CAVAS)

OBJECTIVES

Limited and inconsistent prospective evidence exists regarding the relationship of dietary total antioxidant capacity (dTAC) and antioxidant intake with metabolic syndrome (MetS) risk. We evaluated the associations of the cumulative averages of dTAC and antioxidant intake (in 5 classes: retinol, vitamin C, vitamin E, carotenoids, and flavonoids, as well as 7 flavonoid subclasses) with the risk of MetS.

METHODS

This study included 11,379 participants without MetS, drawn from the Korean Genome and Epidemiology Study_CArdioVascular disease Association Study (KoGES_CAVAS). The cumulative average consumption was calculated using repeated food frequency questionnaires. Incidence rate ratios were estimated using a modified Poisson regression model with a robust error estimator.

RESULTS

The median follow-up period was 5.16 years, and 2,416 cases of MetS were recorded over 58,750 person-years. In men, significant inverse associations were observed in all 5 antioxidant classes, except for the highest quartile of dTAC. In women, dTAC and total flavonoids were not significantly associated with MetS; however, significant L-shaped associations were found for the remaining 4 antioxidant classes. Of the 7 flavonoid subclasses, only flavones in the highest quartile for men and flavan-3-ols in women lacked significant associations with MetS. The inverse associations were not sex-specific, but they were particularly pronounced among participants with a body mass index (BMI) of 23 kg/m2 or higher.

CONCLUSIONS

The findings suggest that most antioxidant classes and flavonoid subclasses, unlike dTAC, exhibit a clear beneficial association with MetS in an L-shaped pattern in both men and women, particularly those with a high BMI.

Effect of Dietary Berry Supplementation on Antioxidant Biomarkers in Adults with Cardiometabolic Risks: A Systematic Review of Clinical Trials

Cardiometabolic conditions are closely associated with inflammation and oxidative stress. Dietary berries may serve as a beneficial nutrition intervention to address the features of cardiometabolic dysfunction and associated oxidative stress. The high antioxidant status of dietary berries may increase antioxidant capacity and reduce biomarkers of oxidative stress. This systematic review was conducted to investigate these effects of dietary berries. The search was conducted using PubMed, Cochrane Library, Web of Science, and citation searching. Through this search we identified 6309 articles and 54 were included in the review. Each study's risk of bias was assessed using the 2019 Cochrane Methods' Risk of Bias 2 tool. Antioxidant and oxidative stress outcomes were evaluated, and the magnitude of effect was calculated using Cohen's d. A range of effectiveness was reported in the included studies and the quality of the studies differed between the parallel and crossover trials. Considering the inconsistency in reported effectiveness, future investigations are warranted to determine the acute and sustained reductions of oxidative stress biomarkers from dietary berry intake (PROSPERO registration# CRD42022374654).

Validation and Comparison of Two Dietary Indexes for Predicting Nonalcoholic Fatty Liver Disease in US Adults

BACKGROUND

Two indexes have been used to describe dietary inflammatory potential: the experiment-based dietary total antioxidant capacity (TAC) and the literature-derived dietary inflammatory index (DII). How robustly each index represents dietary inflammatory potential and the risk of nonalcoholic fatty liver disease (NAFLD) has not yet been established.

OBJECTIVES

We investigated the relation between dietary inflammatory potential and NAFLD, and compared the abilities of the TAC and DII scores to predict NAFLD in US adults.

METHODS

Cross-sectional data from 12,410 participants aged 20-80 y in the NHANES from 2011 to 2018 were identified. TAC and DII scores were calculated using 2 d of 24-h dietary recall data. We examined the association between dietary index and risk of NAFLD using linear and logistic regression models.

RESULTS

Higher energy-adjusted TAC (E-TAC) and inversely energy-adjusted DII (IE-DII) scores (both representing more anti-inflammatory diets) were associated with lower hepatic steatosis index (HSI) and US fatty liver index (USFLI) values after adjusting for potential covariates, and the association for each SD increase in the IE-DII was stronger than the E-TAC (β estimates for HSI: -0.39 compared with -0.25; P-difference = 0.036). In modeling the risk of NAFLD, we observed that participants with IE-DII scores in the highest quartile had the lowest ORs for NAFLD as assessed by either the HSI (OR: 0.77; 95% CI: 0.62, 0.96; P-trend = 0.023) or USFLI (OR: 0.48; 95% CI: 0.35, 0.68; P-trend <0.0001). TAC scores were also associated with NAFLD as assessed by the USFLI.

CONCLUSIONS

An anti-inflammatory diet is beneficial for reducing the risk of NAFLD in US adults. The DII is a stronger predictor of hepatic measures than the TAC, and we recommend that future hepatic health studies use the DII to estimate dietary inflammatory potential.

Evaluation of the predictive value of different dietary antioxidant capacity assessment methods on healthy and unhealthy phenotype in overweight and obese women

Purpose

Predictive value of different dietary antioxidant capacity assessment methods on healthy and unhealthy phenotypes in overweight and obese women is still unclear. This study aimed to evaluate the predictive value of different dietary antioxidant capacity assessment methods on healthy and unhealthy phenotypes in overweight and obese women.

Methods

A total of 290 overweight and obese women were included in this cross-sectional study. Food intake was assessed using a semi-quantitative food frequency questionnaire (FFQ). Dietary antioxidant capacity was calculated using valid databases of antioxidant value. The receiver operating characteristic (ROC) curve method was used to evaluate the predictive value of antioxidant capacity indices, including dietary antioxidant quality score (DAQS), ferric reducing ability of plasma (FRAP), total reactive antioxidant potential (TRAP), and trolox equivalent antioxidant capacity (TEAC).

Results

The results showed that the highest area under the ROC curve for predicting metabolically healthy obesity (MHO) belongs to the TRAP method (area under the curve (AUC) = 0.53). In addition, this method had the highest AUC for predicting inflammatory marker of C-reactive protein (hs-CRP) (AUC = 0.54) and the index of the homeostatic model assessment for insulin resistance (HOMA-IR) (AUC = 0.59). The highest AUC for triglyceride prediction was related to the DAQS method (AUC = 0.56). Moreover, a significant correlation of FRAP (r = -0.15, P = 0.02), TRAP (r = -0.19, P < 0.001), TEAC (r = -0.18, P< 0.001) with HOMA-IR was reached.

Conclusion

The findings of this study show that the best way to predict the status of MHO is TRAP method. This method is also the best predictor of hs-CRP and HOMA-IR. DAQS method is the best predictor for TG.

Dietary total antioxidant capacity is inversely associated with the odds of non-alcoholic fatty liver disease in people with type-2 diabetes

BACKGROUND

This study was conducted to evaluate possible associations between Dietary Total Antioxidant Capacity (DTAC) and odds of non-alcoholic fatty liver disease (NAFLD) in people with type-2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

We recruited two hundred people with T2DM, and evaluated their liver steatosis using Fibroscan. Dietary intakes of participants were assessed using a validated food frequency questionnaire. DTAC was computed via ferric reducing antioxidant power (FRAP).

RESULTS

In the crude model, no statistically significant association was found between DTAC and the odds of NAFLD in people with diabetes. However, after adjustment for potential confounders including age, gender, diabetes duration, smoking status, physical activity, BMI, waist circumference, and energy, the most reduced adjusted OR was indicated for the third tertile vs. the first one (OR: 0.28, 95% CI: 0.09-0.81, P = 0.02), meaning that diabetic patients in the third tertile of DTAC had 72% decreased risk of NAFLD in comparison to those in the first one. The relationship was remained significant after additional adjustment for HOMA-IR, HbA1c, serum Triglyceride (TG), and low-density lipoprotein-cholesterol (LDL) levels (OR: 0.29, 95% CI: 0.09-0.93, P = 0.03). Importantly, a dose-response pattern was demonstrated for DTAC and risk of NAFLD (P = 0.04).

CONCLUSION

Higher DTAC was related with a decreased risk of NAFLD in individuals with diabetes.

Evaluation of The Antioxidant Capacity of Food Products: Methods, Applications and Limitations

Assays of total antioxidant capacity (TAC) are popular in the analysis of food products. This review presents the most popular assays of TAC and their limitations, databases of TAC of food products, their application in clinical studies, and the effect of processing on the TAC of food. The importance of sample preparation for TAC assays and striking effects of digestion in the gastrointestinal tract on the TAC of food are discussed. Critical opinions on the validity of food TAC assays are considered. It is concluded that TAC methods can be useful as screening assays for food quality control and as low-cost, high-throughput tools used to discover potential antioxidant sources and follow changes in the content of antioxidants during food processing. However, effects revealed by TAC assays should be followed and explained using more specific methods.

Dietary total anti-oxidant capacity is inversely related to the prevalence of depression in adolescent girls

Background

Oxidative stress is considered to be a contributory factor for depression, and is affected by the dietary intake of pro-and anti-oxidants. Dietary total antioxidant capacity (DTAC) is an index which is applied to estimate the cumulative power of antioxidants in the whole diet. The aim of this study was to determine the relationship between DTAC and prevalence of depression in adolescent girls.

Methods

A total of 741 Iranian adolescent girls aged 12–18 years were recruited into this cross-sectional study. Dietary intake and depression severity score were assessed using a food frequency questionnaire and Beck's depression inventory, respectively. To estimate the DTAC, the oxygen radical absorbance capacity method was used for selected foods. To explore the associations between DTAC and depression, logistic regression was applied using crude and adjusted models.

Results

Individuals in the greatest adherence to high DTAC had more intakes of whole grains, legumes, fruits, dried fruits, low fat dairy products, cruciferous vegetables, fiber, magnesium, vitamin C, folate, potassium, zinc, β-carotene, lutein, thiamin, riboflavin, niacin and vitamin B-6 and lower consumption of refined grains. Subjects in the highest quartile of DTAC had a 39% lower odds of depression compared to those in the first quartile (OR = 0.61; 95% CI: 0.38–0.97, P for trend = 0.012); these associations remained significant after adjustments in first, second and third (OR = 0.5; 95% CI: 0.28–0.92, P for trend < 0.001) adjusted models.

Conclusions

An inverse association was observed between the DTAC and the prevalence of depression in our population sample of adolescent girls. Further research needs to be conducted in different areas, including longitudinal studies with larger sample sizes.

Interaction between Apo A-II -265T > C polymorphism and dietary total antioxidant capacity on some oxidative stress and inflammatory markers in patients with type 2 diabetes mellitus

This work aims to examine the interaction between apo A2 (Apo A-II) -265T > C SNP and dietary total antioxidant capacity (DTAC) on inflammation and oxidative stress in patients with type 2 diabetes mellitus. The present cross-sectional study included 180 patients (35-65 years) with identified Apo A-II genotype. Dietary intakes were assessed by a FFQ. DTAC was computed using the international databases. IL-18 (IL18), high-sensitivity C-reactive protein (hs-CRP), pentraxin (PTX3), serum total antioxidant capacity (TAC), superoxide dismutase (SOD) activity and 8-isoprostaneF2α (PGF2α) markers were obtained according to standard protocols. General linear model was used to evaluate the interaction. The interaction of gene and DTAC (P_FRAP = 0·039 and P_ORAC = 0·042) on PGF2α level was significant after adjusting for confounders. A significant interaction was observed on IL18 level (P_ORAC = 0·018 and P_FRAP = 0·048) and SOD (P_TEAC = 0·037) in obese patients. Among patients whose DTAC was higher than the median intake, the levels of hs-CRP and PGF2α were significantly higher only in individuals with CC genotype. Serum TAC (P_FRAP = 0·030, P_ORAC = 0·049) and SOD were significantly lower in the CC genotype. There was a favourable relationship between the high-DTAC and SOD (obese: P_TEAC = 0·034, non-obese: P_FRAP = 0·001, P_TRAP < 0·0001, P_TEAC = 0·003 and P_ORAC = 0·001) and PGF2α (non-obese: P_ORAC = 0·024) in T-allele carriers. The rs5082 SNP interacts with DTAC to influence several cardiometabolic risk factors. Also, we found dietary recommendations for antioxidant-rich foods intake might be useful in the prevention of diabetes complications in the T carrier more effectively than the CC genotype. Future large studies are required to confirm these results.

Interplay between fatty acid desaturase2 (FADS2) rs174583 genetic variant and dietary antioxidant capacity: cardio-metabolic risk factors in obese individuals

OBJECTIVE

Polymorphisms of the fatty acid desaturase (FADS) gene cluster have been associated with obesity and its-related consequences. This cross-sectional study aimed to investigate whether the adherence to dietary non-enzymatic antioxidant capacity (NEAC), reflecting the antioxidant potential of the whole diet, modifies the association of FADS2 rs174583 polymorphism with cardio-metabolic risk factors in obese adults.

METHODS

The present study included 347 healthy obese adults (aged 20-50 years). Dietary NEAC was assessed by a validated food frequency questionnaire with 147 items and estimated through total radical-trapping antioxidant parameters (TRAP), oxygen radical absorbance capacity (ORAC), and ferric reducing ability of plasma (FRAP) with the use of published databases. FADS2 rs174583 polymorphism was characterized using PCR-RFLP. ANCOVA multivariate interaction model was used to analyze gene-diet interactions.

RESULTS

after adjustment for the confounding variables (age, physical activity, SES and WC), this study showed significant interactions between rs174583 polymorphism and adherence to dietary ORAC on the serum cholesterol (P _Interaction = 0.029), LDL-C (P _Interaction = 0.025) and HDL-C levels (P _Interaction = 0.049) among the male group; minor allele carriers who had the highest adherence to the NEAC (ORAC) showed a better metabolic profile (lower TG and LDL-C and higher HDL-C) (P < 0.05). Among women, the dietary ORAC-rs174583 interactions were statistically significant for the serum insulin concentration (P _Interaction = 0.020), QUICKI (P _Interaction = 0.023) and HOMA-IR (P _Interaction = 0.017); the highest QUICKI and the lowest HOMA-IR and serum insulin levels were observed in the CC homozygote carriers with the moderate compliance with the dietary ORAC (P < 0.05). In addition, the dietary TRAP modified the association between FADS2 variant and change in LDL-C levels (P _Interaction = 0.037); the homozygous wild-type (CC) women who placed in the top tertile of TRAP had significantly the lowest LDL-C levels than those in the second tertile (P < 0.05).

CONCLUSION

These data indicate that the FADS2 rs174583 polymorphism interacts with the dietary NEAC to influence cardio-metabolic risk factors in obese subjects. Replication in prospective cohort studies among other populations is required to confirm the results of our study.

The Interaction Between Dietary Total Antioxidant Capacity and MC4R Gene and HOMA-IR in Metabolically Healthy and Unhealthy Overweight and Obese Women

Introduction

The current prevalence of the metabolically healthy obesity is about 3%. Genetic and nutrition are influencers of such phenotypes. The main goal of this study was to assess the interaction between Dietary Total Antioxidant Capacity (DTAC) and the genotypes of MC4R and Insulin resistance in metabolically healthy/unhealthy overweight and obese women in Iran.

Material And Methods

This cross-sectional study was conducted on 237 overweight-obese women with a mean age of 36. The value of Dietary total antioxidant capacity (DTAC) was calculated using the following indices: Total reactive antioxidant potential (TRAP), Trolox equivalent antioxidant capacity (TEAC), and ferric reducing ability of plasma (FRAP). The Metabolic health status was evaluated using the Karelis criteria. Melanocortin 4 receptor single nucleotide polymorphisms were determined by the restriction fragment length polymorphism (PCR-RFLP) method. Also, insulin resistance was evaluated through homeostasis model assessment (HOMA).

Result

Our data noted that 72.96% of participants presented Unhealthy Metabolically and 26.94% Healthy Metabolically including 33.5% of the total had T/T genotype, 23.8% had the C/T genotype, and 42.5% had the C/C genotype (P = .05). A linear regression model test showed that the probability of metabolically healthy obesity was significantly higher in patients with the T/C genotype. The test value was statistically significant (95% CI: 0.000-0.001; P = .056, β = 0). No statistically significant relation was observed between study parameters and DTAC values. HOMA-Index was higher in all unhealthy subjects significantly.

Conclusions

The findings indicated that there are significant associations between genotypes of rs1333048 SNP and DTAC. The C/C genotype subjects with higher DTAC had a better lipid profile and were metabolically healthier.

Higher dietary total antioxidant capacity is inversely associated with Helicobacter pylori infection among adults: A case-control study

INTRODUCTION

Antioxidants appear to hinder the actions of Helicobacter pylori (H. pylori). The aim of this research was to evaluate the association between dietary total antioxidant capacity (DTAC) and H. pylori infection.

METHODS

A case-control study was carried out among 200 patients with  H. pylori infection and 402 healthy subjects (18-55 years). Dietary data were collected using a validated 168-item quantitative food frequency questionnaire. DTAC was calculated based on the oxygen radical absorbance capacity of each food (except for coffee) reported by the US Department of Agriculture.

RESULTS

Compared with participants in the lowest tertile of DTAC, those in the highest tertile had a significantly lower odds ratio (OR) in the crude model (OR, 0.29; 95% CI, 0.14-0.61; p for trend = 0.001), model 1 (adjustment for age and sex) (OR, 0.37; 95% CI, 0.24-0.58; p for trend < 0.001), and model 2 (adjustment for model 1 plus body mass index, waist circumference, physical activity, smoking, dietary intake of energy and fat) (OR, 0.20; 95% CI, 0.10-0.40; p for trend ≤ 0.001).

CONCLUSIONS

A high DTAC is associated with a reduced risk of H. pylori infection in adults. Further studies are mandatory to elucidate the mechanisms and a dose-effect relationship.

Dietary total antioxidant capacity and its association with renal function and kidney stones: Results of a RaNCD cohort study

There is evidence to support the hypothesis that dietary antioxidants have shown protective effects against chronic kidney disease (CKD). The purpose of this study was to determine the association between the dietary total antioxidant capacity (DTAC), renal function, and development of CKD and kidney stones in Ravansar Non‐Communicable Diseases (RaNCD) cohort study, Kermanshah, Iran. This cross‐sectional study was conducted using the recruitment baseline data of the RaNCD cohort study on 9,777 individuals aged 35–65 years. Food frequency questionnaire (FFQ) was performed to assess diet. DTAC scores were calculated using the ferric reducing antioxidant power (FRAP) of selected foods. Renal function was assessed by the estimated glomerular filtration rate (eGFR), blood urea nitrogen, and serum creatinine concentration. Prevalent CKD was based on an eGFR less than <60 ml/min per 1.73 m². Incidence of kidney stones was also assessed by self‐reporting. Out of 9,777 participants, 1,747 subjects (eGFR: 18.50 ml/min per 1.73 m²; 95% confidence interval (CI): 17.72–19.30) had CKD. The mean DTAC score in this study was 0.24 ± 0.16 µmol TE/100 g (micromole of Trolox Equivalents). We showed a significant trend for eGFR across quartiles of DTAC, i.e., participants in the fourth quartile had a higher glomerular filtration rate (GFR) than those in the first one (DTAC _{Q4 vs Q1} = 82.20 versus 72.20 ml/min per 1.73 m², p < .001). Another finding is that high DTAC scores were not associated with having kidney stones after adjusting for confounders. We revealed that higher DTAC scores have positive effects on the renal function. Interestingly, our findings showed that a high DTAC score had nonsignificant correlation with odds of kidney stones.

Association Between Dietary Total Antioxidant Capacity and Diet Quality in Adults

Background

Diet quality is a major contributor to human health. In addition, antioxidants have a great contribution to several chronic conditions. The purpose of this study was to evaluate if dietary total antioxidant capacity (TAC) can be considered as a measure of diet quality in a Middle Eastern country.

Methods

In this cross-sectional study on 6,724 Iranian adults, we used a validated food frequency questionnaire (FFQ) to assess dietary intakes. Data derived from the FFQ was used to calculate dietary TAC and well-known diet quality scores including alternate healthy eating index (AHEI) and dietary diversity score (DDS). Dietary TAC was calculated based on the ferric reducing-antioxidant power (FRAP) values reported in earlier publications. AHEI and DDS have also been constructed based on previous publications. Cross-classification was used to examine the agreement between these measures.

Results

Mean age and BMI of study participants were 36.89 ± 8.08 y and 24.97 ± 3.87 kg/m², respectively. We found that individuals in the highest tertile of dietary TAC had higher scores of AHEI (57.53 ± 0.20 vs. 52.03 ± 0.20, P < 0.001) and DDS (5.56 ± 0.03 vs. 4.15 ± 0.03, P < 0.001) compared with those in the lowest tertile. Participants' distribution on the basis of the cross-classification analysis indicated that the classifications were in exact agreement for 42.6%, within an adjacent tertile for 33.05%, and in gross misclassification for 20% of individuals. When this was examined between dietary TAC and DDS, we found that exact agreement in the classifications was for 59.2% of participants. Notably, a very low proportion of gross misclassification was seen in this regard such that only 6% of participants were classified in the opposing tertiles, indicating additional support for a good agreement.

Conclusion

We found that dietary TAC might be considered as a proper measure for the assessment of diet quality because it was well correlated with well-known measures of diet quality including DDS and AHEI scores.

Relationship between Habitual Intake of Vitamins and New-Onset Prediabetes/Diabetes after Acute Pancreatitis

Vitamins have many established roles in human health. However, the role of habitual dietary intake of vitamins in glucose homeostasis in individuals after acute pancreatitis (AP) is yet to be elucidated. The aim was to investigate the associations between habitual intake of fat- and water-soluble vitamins/vitamers and markers of glucose metabolism (fasting plasma glucose (FPG), homeostasis model assessment insulin resistance (HOMA-IR) index, and homeostasis model assessment β-cell function (HOMA-β)) in individuals after AP. A total of 106 participants after AP were included in this cross-sectional study and were grouped based on glycaemic status: new-onset prediabetes/diabetes after AP (NODAP), pre-existing prediabetes/type 2 diabetes (T2DM), and normoglycaemia after AP (NAP). Habitual intake of seven fat-soluble vitamins/vitamers and seven water-soluble vitamins were determined by the EPIC-Norfolk food frequency questionnaire. Multiple linear regression analyses were conducted using five statistical models built to adjust for covariates (age, sex, daily energy intake, visceral/subcutaneous fat volume ratio, smoking status, daily alcohol intake, aetiology of AP, number of AP episodes, cholecystectomy, and use of antidiabetic medications). In the NODAP group, three fat-soluble vitamins/vitamers (α-carotene, β-carotene, and total carotene) were significantly associated with HOMA-β. One water-soluble vitamin (vitamin B3) was also significantly associated with HOMA-β in the NODAP group. None of the studied vitamins were significantly associated with FPG or HOMA-IR in the NODAP group. Prospective longitudinal studies and randomised controlled trials are now warranted to investigate if the observed associations between vitamin/vitamer intake and NODAP are causal and to unveil the specific mechanisms underlying their involvement with NODAP.

Cryoconcentration by Centrifugation–Filtration: A Simultaneous, Efficient and Innovative Method to Increase Thermosensitive Bioactive Compounds of Aqueous Maqui (Aristotelia chilensis (Mol.) Stuntz) Extract

Maqui (Aristotelia chilensis (Mol.) Stuntz) is a Chilean berry rich in antioxidants, which are mostly found in the pulp and skin of the fruit. The objective was to evaluate the cryoconcentration process by centrifugation–filtration as a simultaneous, efficient, and innovative method to increase the content of thermosensitive bioactive compounds of aqueous maqui extract. Cryoconcentration separated the concentrated solute from the aqueous maqui extract with an efficiency of more than 95%; it increased the content of total polyphenols and total anthocyanins and antioxidant capacity by 280%, 573%, and 226%, respectively. Although the concentrates obtained by evaporation at 50, 70, and 80 °C increased the content of bioactive compounds, they did so in a lower percentage than the cryoconcentrate. Furthermore, cyanidin 3,5-diglucoside was degraded at 70 and 80 °C. In conclusion, cryoconcentration by centrifugation–filtration as a simultaneous process efficiently separates the solutes from the frozen matrix of aqueous maqui extract, and it maintains and increases the contents of polyphenols and anthocyanins and antioxidant capacity. This method is recommended for concentrating natural berry extracts with thermosensitive compounds.

The Association of Dietary Total Antioxidant Capacity with Inflammatory Biomarkers and Anthropometric Indices in Patients Who Candidate for Coronary Artery Bypass Graft Surgery: a Cross-sectional Study

Antioxidant compounds can attenuate inflammation and delay degenerative processes especially in the cardiovascular system. This study aimed to determine the relationship between dietary total antioxidant capacity (DTAC) and serum biomarkers in patients undergoing coronary artery bypass graft surgery. In this cross-sectional study, 146 patients who had referred to Imam Ali Hospital in Kermanshah were recruited and demographic, anthropometric, physical activity and dietary data were collected. Fasting blood glucose (FBG), serum levels of lipid profile, inflammatory markers (interleukin [IL]-17, intercellular and vascular cell adhesion molecules [ICAM, VCAM]), and total antioxidant capacity (TAC) were also measured. A regression model adjusted for confounding variables presented that the coefficients of ICAM and VCAM (ng/dL) in the third tertile of DTAC were lower than those in the first tertile (β = -417.2, 95% confidence interval [CI] = -509.9 to -324.5, p < 0.001; β = -293.2, 95% CI = -334.3, -252.1, p < 0.001, respectively). The β of serum TAC (ng/dL) in the third tertile was 0.86 (95% CI = 0.77, 0.95, p < 0.001) higher than that in the first tertile. DTAC had no statistically significant relationship with lipid profile, FBG, and IL-17 levels, and anthropometric indices. In this study DTAC was associated with increased serum TAC and decreased cell adhesion molecules. Therefore, diet antioxidants may be beneficial in attenuating of inflammation in coronary artery diseases.

Interaction between dietary total antioxidant capacity and BDNF Val66Met polymorphism on lipid profiles and atherogenic indices among diabetic patients

Brain-derived neurotrophic factor (BDNF) belongs to the "neurotrophin" family of growth factors, and it has recently been associated to cardiovascular disease (CVD). We anticipated that BDNF Val66Met polymorphisms may alter CVD risk markers such as serum lipid profile differences, and interaction with total antioxidant capacity of diet (DTAC) could alter these clinical parameters. This cross-sectional study consisted of 667 diabetic patients (39.7% male and 60.3% female). DTAC was calculated by international databases. Biochemical markers including total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglyceride (TG), superoxide dismutase (SOD), C-reactive protein (CRP), total antioxidant capacity (TAC), pentraxin-3 (PTX3), isoprostaneF2α (PGF2α). interleukin 18 (IL18), leptin and ghrelin were measured by standard protocol. Atherogenic indices (AIP, AC, CR-I, CR-II) were calculated. Genotyping of the BDNF Val66Met polymorphisms was conducted by the real-time PCR-RFLP method. The gene-diet interactions were evaluated using a generalized linear mode (GLMs). Carriers of the Val/Met genotype who were in the higher median intake of FRAP had lower HDL (P:0.04) and higher TG (P:0.005), AIP (P:0.02) and AC (P:0.02) index compared to Val/Val genotypes with lower median intake. Moreover, diabetic patients with Val/Met genotype who consumed higher ORAC intake had increased odds for anthropometric indices (BMI (P:0.01) and WC (P:0.03)), lipid profiles (TG) (P:0.01), and atherogenic index (AIP) (P:0.02), also decreased odds for HDL (P:0.03) concentration compared to reference group whit lower ORAC intake. Individuals with Val/Met genotype who consumed higher TRAP intake had increased odds for WC (P:0.04), TC (P:0.001), TG (P < 0.001), AIP (P < 0.001) and AC (P < 0.001). Finally, Val/Met patients with a higher median intake of TEAC had higher TG (P:0.02), AIP (P:0.009) and AC (P:0.03) compared to the reference group whit lower TEAC intake. Our study showed that Val/Met genotype had also the highest lipid profile and atherogenic indices even in the highest adherence to DTAC. While it seems that the presence of the Val/Val wild-type and BDNF Met/Met homozygotes in diabetic patients with a high DTAC is a protective factor.

Healthy Eating Index-2015 and Dietary Total Antioxidant Capacity as Predictors of Prediabetes: A Case-Control Study

BACKGROUND

The overall dietary quality, as well as the dietary total antioxidant capacity (DTAC), deserves central attention in the management of borderline high glucose levels since nonpharmacological strategies are imperative in this regard. Thus, we aimed to investigate the association between prediabetes with dietary quality and DTAC.

METHODS

A case-control study was conducted on 49 patients with prediabetes and 98 controls. Demographics, anthropometric measures, and fasting blood glucose levels of all participants were obtained. Participants completed a validated 80-item food frequency questionnaire (FFQ). DTAC scores were generated using FFQ data, and Healthy Eating Index-2015 (HEI-2015) was used as a diet quality index. The lowest tertile of HEI-2015 and DTAC was considered as the reference category, and logistic regression was used to estimate the relationship between prediabetes with HEI-215 and DTAC.

RESULTS

Mean age and body mass index of participants were 47.42 ± 15.98 years and 27.90 ± 4.96 kg/m2. Patients with prediabetes had lower DTAC scores when compared to controls (11.86 ± 5.77 and 17.81 ± 12.08, P = 0.01). There was a significant inverse association between the highest tertile of the DTAC score when compared with the lowest tertile in crude (OR = 0.11; 95% CI: 0.03-0.43), age-adjusted (OR = 0.13; 95% CI: 0.03-0.48), and fully adjusted (OR = 0.09; 95% CI: 0.02-0.53) models. In contrast, there was no difference between HEI-2015 in patients with prediabetes when compared to controls (74.41 ± 8.91 and 74.41 ± 9.35, respectively; P = 0.85). Correspondingly, no difference was observed between the highest tertile of the HEI-2015 score when compared with the lowest tertile in crude (OR = 1.23; 95% CI: 0.53-2.86), age-adjusted (OR = 1.17; 95% CI: 0.48-2.82), and fully adjusted (OR = 1.53; 95% CI: 0.56-4.16) models.

CONCLUSION

This study demonstrates a clear association between prediabetes with less DTAC, but not with HEI-2015.

The effect of dietary total antioxidant capacity (DTAC) and Caveolin-1 gene variant interaction on cardiovascular risk factors among overweight and obese women: A cross-sectional investigation

BACKGROUND

Previous studies have shown that the Caveolin-1 (CAV-1) gene variant may be associated with Cardiovascular disease (CVD) risk. Moreover, dietary total antioxidant capacity (DTAC) has been shown to potentially elicit favorable effects on CVD risk. Therefore, this study sought to investigate the effect of DTAC and CAV-1 interaction on CVD risk factors.

METHODS

This cross-sectional study consisted of 352 women, with overweight and/or obesity, aged 18-48years from Iran. A food frequency questionnaire (FFQ), with 147 items, was used to assess dietary intake. The CAV-1 rs 3807992 and anthropometric data were measured by the PCR-RFLP method and bioelectrical impedance analysis (BIA), respectively. Serum profiles were measured by standard protocols. Participants were also divided into two groups based on DTAC score and rs3807992 genotype.

RESULTS

The mean age of the participants was 37.34 ± 9.11 and 36.01 ± 9.12 years for homozygous (GG) and minor allele carriers (AG + AA) respectively.The mean ± SD of insulin, total cholesterol (TC),high-density lipoprotein (HDL), low-density lipoprotein (LDL) and TG of participants were 1.21 ± 0.23, 185.3 ± 35.77, 46.58 ± 10.86, 95.3 ± 24.12 and 118.1 ± 58.88, respectively. There was a significant difference between genotypes for physical activity (P = 0.05), HDL (P < 0.001), insulin (P = 0.04), CRI-I (TC/HDL-C) (P = 0.01), and CRI-II (LDL-C/HDL-C) (P = 0.04). Our findings also showed, after controlling for confounding factors, significant interactions between DTAC score and the A allele carrier group on TC (Pinteraction = 0.001), LDL (Pinteraction = 0.001), insulin (Pinteraction = 0.08), HOMA-IR (Pinteraction = 0.03), AC ((TC - HDL - C)/HDL - C) (Pinteraction = 0.001), and CHOLINDEX (LDL-C-HDL-C) (Pinteraction = 0.02).

CONCLUSION

The results of the present study indicate that high DTAC intake may modify the odds of risk factors for CVD in AA and AG genotypes of rs 3807992. These results highlight that diet, gene variants, and their interaction, should be considered in CVD risk assessment.

Association of dietary total antioxidant capacity with anthropometric indicators, C-reactive protein, and clinical outcomes in hospitalized oncologic patients

OBJECTIVE

Many studies have shown an inverse association between higher dietary total antioxidant capacity (DTAC) and chronic non-communicable diseases, including cancer. The aim of this study was to evaluate the association of the DTAC with anthropometric and biochemical indicators and clinical outcomes in hospitalized patients with cancer.

METHODS

A cross-sectional study was carried out with 196 hospitalized patients diagnosed with cancer. The DTAC, determined by the ferric-reducing antioxidant power method, was calculated using a validated standard spreadsheet. Multivariate linear regression was used to assess the association, identifying anthropometric indicators that were associated with DTAC and the variables of interest. P < 0.05 was statistically significant.

RESULTS

The individuals included in the last tertile of DTAC presented lower occurrences of death (P = 0.032), constipation (P = 0.010), dysphagia (P = 0.010), painful swallowing and chewing (P = 0.019), and dehydration (P = 0.032) than individuals in the first tertile. The C-reactive protein values were significantly lower (P = 0.010) and handgrip strength values were higher (P = 0.037) in individuals in the third tertile than in the other participants.

CONCLUSIONS

DTAC was associated with a better prognosis of hospitalized cancer patients, considering signs and symptoms of nutritional impact, as well as the inflammatory state of the patients. These factors may influence the length of hospital stay and mortality. The findings of this research provide important information for a preventive and nutritional management perspective in this population.

Association of Oxidative Balance Score with the Metabolic Syndrome in a Sample of Iranian Adults

Objective

We aimed to assess the association of the oxidative balance score (OBS) with metabolic syndrome (MetS) in adults.

Design

A population-based cross-sectional study Setting. Health centers from five districts in Tehran, Iran.

Methods

We recruited 847 participants with an age range of 18-65 years. Dietary intake was assessed by a semiquantitative food frequency questionnaire with 168 items. The OBS was calculated by using the following 13 dietary and nondietary anti- and prooxidant components: dietary antioxidants (selenium, fiber, β-carotene, vitamin D, vitamin C, vitamin E, and folate), dietary prooxidants (iron and saturated and polyunsaturated fatty acids), and nondietary anti- (physical activity) and prooxidants (smoking and obesity). The odds ratio (OR) and 95% confidence interval (CI) of the MetS and its components across tertiles of the OBS were calculated by logistic regression analysis, controlling for age, sex, energy intake, occupation, and educational level.

Results

The range of OBS was between 16 and 39. Being in the top versus the bottom tertile of the OBS was not associated with the MetS (OR = 0.71, 95% CI 0.48-1.03; P = 0.07), after controlling for potential confounders. Higher OBS score was associated with a lower likelihood of abdominal obesity (OR: 0.55, 95% CI: 0.38-0.81; P = 0.003) and increased diastolic blood pressure (OR: 0.64, 95% CI: 0.41-0.99; P = 0.04). Higher OBS was not associated with other components of the MetS.

Conclusion

Overall, the present study showed that there was no significant relationship between OBS and MetS in Tehranian adults.

Prevalence of Metabolic Syndrome in Children and Adolescents with Type 1 Diabetes Mellitus and Possibilities of Prevention and Treatment: A Systematic Review

Overweight and obesity are an increasingly common problem, not only among the healthy population, but also in adolescents with type 1 diabetes (T1DM). Excess body weight is related to many cardiometabolic complications as well as a high risk of metabolic syndrome (MetS). The purpose of this systematic review is to provide a concise and critical overview of the prevalence of MetS in children and adolescents with T1DM and, ultimately, to discuss prevention and treatment options. The study was conducted in accordance with PRISMA guidelines. This review shows that, apart from the growing percentage of overweight and obese children and adolescents with T1DM (on average 20.1% and 9.5%, respectively), the problem of the increasing incidence of MetS (range from 3.2 to 29.9%, depending on the criteria used) is one of the most important phenomena of our time. One of the methods of prevention and treatment is a combined approach: changing eating habits and lifestyle, but there are also reports about the beneficial effects of the gut microflora.

Higher dietary total antioxidant capacity (TAC) reduces the risk of cardio-metabolic risk factors among adults: An updated systematic review and meta-analysis

Background: Numerous studies have revealed the protective role of dietary antioxidants against hypertension and diabetes. In the current systematic review and meta-analysis, we evaluated the possible role of dietary total antioxidant capacity (TAC) against metabolic parameters in the adult population. Methods: A literature search of authentic electronic resources including PubMed, Scopus, Web of Sciences, and Cochrane had been performed to retrieve the qualified observational studies that reported the mean plus/minus the SD for the parameter in subjects of the highest versus lowest dietary TAC categories up to July 2020. Results: Totally, the number of included studies was 13 for fasting blood sugar (FBS), 12 for systolic blood pressure (SBP), and 12 for diastolic blood pressure (DBP), with the participants' number of 26349. The results of the current study showed that being at highest category of TAC significantly reduces serum FBS (WMD: -2.381; CI: -3.445, -1.316; P<0.001), SBP (WMD: -1.080; CI: -1.458, -0.701; P<0.001) and DBP (WMD: -0.854; CI: -1.655, -0.052; P<0.001), while no significant difference in the serum insulin, HOMA-IR values, prevalence of type 2 diabetes (T₂DM) (P=0.37) and hypertension (HTN) (P=0.09) was observed. Subgroup analysis revealed the geographical location, dietary assessment tool, sample size, and gender as possible sources of heterogeneity. Conclusion: Higher intake of dietary TAC was associated with reduced SBP, DBP, and FBS in the current observational studies of this meta-analysis. These findings further confirm the clinical importance of dietary antioxidants in the prevention of different metabolic disorders.

Anthropometric and Biochemical Measures in Bariatric Surgery Candidates: What Is the Role of Inflammatory Potential of Diet?

BACKGROUND

The present study aimed to assess dietary total antioxidant capacity (TAC), dietary phytochemical intake (PI), and dietary inflammatory index (DII) in patients with morbid obesity who are candidates of bariatric surgery and their association with anthropometric and biochemical parameters.

METHODS AND MATERIALS

One hundred seventy patients with morbid obesity who were referred to surgery clinic of Firoozgar Hospital were enrolled in the study. Ideal body weight and adjusted ideal body weight were calculated. The dietary data were collected using a food frequency questionnaire. Anthropometrics and biochemical parameters were assessed. A p-value of <0.05 was considered significant.

RESULTS

The strongest correlations of DII with dietary intakes and anthropometric and biochemical biomarkers were found for iron (p<0.0001). Significant association was also observed for ferritin (p=0.02) and transferrin (p=0.02). In terms of PI, The strongest associations were also found for iron (p<0.0001). Additionally, the value of body mass index (BMI) showed significant correlation with PI (p=0.04). The correlations of dietary total antioxidant indices with dietary intakes and anthropometric and biochemical biomarkers were assessed. Non-significant correlation was found between fasting blood sugar (FBS), hemoglobin A1C (HbA1C), vitamin B12, and vitamin D3 with ORAC index. Significant strong correlation showed for the value of iron in both ferric reducing ability of plasma (FRAP) and Oxygen Radical Absorbance Capacity (ORAC) indices (p<0.0001).

CONCLUSION

We find statistical significance correlation for dietary PI and BMI. The inflammatory and antioxidant properties of diet were not related to biochemical markers associated with obesity. Graphical abstract.

Diet Quality Indices and Their Correlation with Glycemic Status and Lipid Profile in Patients with Type 2 Diabetes

BACKGROUND

The study aimed to determine the correlation between different diet quality indices and glycemic status and lipid profile in patients with diabetes.

METHODS

This study was carried out on 235 patients with type 2 diabetes referred to Martyr Motahari Diabetes Clinic of Shiraz city so as to investigate the relationship between glycemic status and lipid profile and the diet quality using Healthy Eating Index (HEI-2010), phytochemical index (PI), and Diet Quality Index-International (DQI_I).

RESULTS

A positive correlation was indicated between the serum levels of LDL-C and HEI-2010 scores (p=0.026). Furthermore, there was a positive correlation between the patients' age and scores of PI (p=0.006) and between PI and DQI_I (p < 0.001). There was no significant relationship between the scores for all three indicators and biochemical parameters.

CONCLUSION

The results of this study indicated that there was a significant correlation between the serum LDL-C levels and the HEI-2010 scores. Moreover, the age of the patients had a direct correlation with the PI scores.

Interaction between Apo A-II -265T>C polymorphism and dietary total antioxidant capacity on some anthropometric indices and serum lipid profile in patients with type 2 diabetes mellitus

The present study aimed to investigate the interaction of Apo A-II polymorphism and dietary total antioxidant capacity (DTAC) with lipid profile and anthropometric markers in patients with type 2 diabetes (T2DM) that are at risk for atherosclerosis. This cross-sectional study was conducted on 778 patients with T2DM (35–65 years). Dietary intakes were assessed by a 147-item food frequency questionnaire. DTAC was computed using international databases. Participants were categorised into two groups based on rs5082 genotypes. The gene–diet interaction was analysed by an ANCOVA multivariate interaction model. Total cholesterol, TC; triacylglycerol, TG; high- and low-density lipoprotein, HDL and LDL; TC–HDL ratio; waist circumference, WC and body mass index, BMI were obtained according to standard protocols. Overall, the frequency of CC homozygous was 12⋅1 % among study participants. We found that a significant interaction between rs5082 variants and DTAC on mean WC (P_TEAC = 0⋅044), TC concentration (P_FRAP = 0⋅049 and P_TEAC = 0⋅031) and TC/HDL (P_FRAP = 0⋅031 and P_TRAP = 0⋅040). Among patients whose DTAC was higher than the median intake, the mean of weight, WC and TC/HDL were significantly higher only in individuals with CC genotype. Also, the high DTAC was associated with a lower TC concentration only in T-allele carriers (P_FRAP = 0⋅042). We found that adherence to a diet with high total antioxidant capacity can improve the complications of diabetes and atherosclerosis in the T carrier genotype more effectively than the CC genotype. These results could indicate the anti-atherogenic properties of Apo A-II. However, further studies are needed to shed light on this issue.

Dietary Total Antioxidant Capacity and Its Association with Renal Function and Progression of Chronic Kidney Disease in Older Adults: a Report from a Developing Country

While evidence exists for an association between the dietary total antioxidant capacity (DTAC), mortality, metabolic syndrome, and cardiovascular diseases, data about DTAC and renal function, and progression of chronic kidney disease (CKD) are scarce. This study aimed to determine the associations between DTAC, renal function, and progression of CKD in older adults. The present cross-sectional study consisted of 226 older adults aged ≥ 60 years old from five districts of Tehran, Iran. DTAC was estimated using the oxygen radical absorbance capacity (ORAC) method. Dietary intake, socio-demographic data, medical history, and anthropometric measurements were collected using a validated questionnaire. The estimated glomerular filtration rate (eGFR) was assessed from serum creatinine. Albumin to creatinine ratio (ACR) was calculated by dividing albumin concentration by creatinine concentration and reported as mg/g. The DTAC ranged from 112.8 to 2,553.9. Analyses indicated that DTAC was not associated with eGFR (p = 0.35) and ACR (p = 0.91) even after controlling for confounding variables. Additionally, in logistic regression, no association between eGFR < 60 mL/min/1.73 m² (p = 0.32) and ACR ≥ 30 mg/g (p = 0.32) with DTAC was observed, which was independent of confounding variables. We observed that more compliance with DTAC is not associated with renal function and CKD progression. Further studies are needed to confirm the findings of the present study in larger samples on different populations.

Twenty-five years of total antioxidant capacity measurement of foods and biological fluids: merits and limitations

This review summarises 25 years of investigations on antioxidants research in foods and biological fluids and critically analyses the merits and limitations of using the total antioxidant capacity (TAC) measurement in the metabolomic era. An enormous bulk of knowledge was produced regarding the antioxidant capacity of foods and large TAC databases were developed. A direct link between a food TAC value and any health benefit is erroneous and has led to several cases of consumer deception. However, the striking epidemiological evidence associating a high dietary TAC with some disease prevention and the availability of well-constructed TAC databases deserve attention and must be taken into account to establish the usefulness of measuring TAC in both foods and biological samples. The in vivo TAC measurement, usually performed in plasma, is influenced by many external factors, such as dietary habits, as well as environmental and behavioural factors, which are integrated towards homeostatic control by fine physiological mechanisms with high inter-individual variability. Therefore, plasma TAC cannot be considered as a unique biomarker of individual antioxidant status. However, the combined evaluation of plasma TAC with known markers of disease, individual metabolism, inflammation and genetics, as well as with markers of gut microbiota composition and activity, may lead to the identification of populations that are more responsive to food/diet TAC. In this framework, the appropriate use of TAC measurement both in food and in vivo can still provide support for the interpretation of complex phenomena and be a tool for sample screening when making a quick decision toward in-depth research investigations. © 2018 Society of Chemical Industry.

Dietary Total Antioxidant Capacity and Gestational Diabetes Mellitus: A Case-Control Study

Background

Elevated oxidative stress status has been reported among pregnant women with gestational diabetes mellitus (GDM). In diabetic condition, glucose and lipid peroxidation, and alteration in antioxidant defense lead to increased free radicals. The objective of this study was to investigate the association between dietary total antioxidant capacity (DTAC) and GDM.

Methods

This hospital-based case-control study was conducted in 463 pregnant women (healthy, n = 263; GDM, n = 200). Anthropometric indices, blood pressure, and biochemical analyses were measured. Dietary intake was assessed by the average of three 24-hour dietary intake records. DTAC was calculated by three indices: ferric reducing ability of plasma (FRAP), total radical-trapping antioxidant parameter (TRAP), and Trolox equivalent antioxidant capacity (TEAC). Multivariable logistic regression was performed to examine the relationship between DTAC and GDM risk in crude and adjusted models.

Results

The mean age and BMI were 28.33 ± 6.23 years and 29.67 ± 4.73 kg/m², respectively. Total energy, protein, and selenium intakes were significantly higher in cases than controls (P < 0.05). Moreover, intakes of carbohydrate, vitamins C, B6, and A, manganese, fruits, fruit juices, vegetables, legumes, and FRAP were significantly lower in cases than controls (P < 0.05). The risk of gestational diabetes mellitus was 85% lower among those in the highest tertile of FRAP (OR: 0.15; 95% CI: 0.08-0.29). There was no significant association between the risk of GDM and TRAP (OR: 1.62; 95% CI: 0.94-2.79) as well as TEAC (OR: 1.56; 95% CI: 0.89-2.72).

Conclusion

Pregnant women who were in the highest tertile of FRAP were at lower risk of GDM. However, larger prospective studies are needed to confirm our findings.

Dietary total antioxidant capacity (TAC), general and central obesity indices and serum lipids among adults: An updated systematic review and meta-analysis

Background: In the present meta-analysis, we aimed to summarize the relationship between dietary total antioxidant capacity (TAC), general and central obesity indices and lipid profile in adult population. Methods: The electronic databases of Web of Sciences, PubMed, Scopus and Cochrane library were searched for relevant studies from inception to October 2019. The effect size was indicated as weighted mean difference (WMD) and 95% confidence intervals (CI) by using random effects model. The I² index and Cochran's Q-test were used for evaluating heterogeneity. Results: From 2,469 studies identified, thirty-four studies (nineteen cross-sectional studies, thirteen cohort studies, two case-control studies) were included in the meta-analysis. According to our results, higher categories of TAC were associated with significantly lower serum triglyceride concentartions (TG; WMD: -7.58; CI: -11.42, -3.75; P < 0.001) and waist circumference (WC; WMD: -1.17; 95% CI: -1.47, -0.87; P < 0.001); while no significant change in body mass index (BMI; WMD: -0.17; 95% CI: -0.35, 0.01; P = 0.12), high density lipoprotein cholesterol (HDL-C; WMD: 0.61; 95% CI: -0.16, 1.40; P = 0.12), low density lipoprotein cholesterol (LDL-C; WMD: 1.34; 95% CI: -0.61, 3.30; P = 0.17) and total cholesterol (TC; WMD: 1.19; 95% CI: -1.46, 3.855; P = 0.37) was reported. Conclusion: Higher dietary TAC was related to reduced prevalence of central obesity, reduced WC and TG concentrations in the current meta-analysis. Moreover, subgroup analysis showed that TAC measurement index, geographical area, dietary assessment tool, health status and gender were potential sources of heterogeneity.

Total Dietary Antioxidant Capacity and Longitudinal Trajectories of Body Composition

Although there is some evidence that total dietary antioxidant capacity (TDAC) is inversely associated with the presence of obesity, no longitudinal studies have been performed investigating the effect of TDAC on comprehensive measures of body composition over time. In this study, we included 4595 middle-aged and elderly participants from the Rotterdam Study, a population-based cohort. We estimated TDAC among these individuals by calculating a ferric reducing ability of plasma (FRAP) score based on data from food-frequency questionnaires. Body composition was assessed by means of dual X-ray absorptiometry at baseline and every subsequent 3–5 years. From these data, we calculated fat mass index (FMI), fat-free mass index (FFMI), android-to-gynoid fat ratio (AGR), body fat percentage (BF%) and body mass index (BMI). We also assessed hand grip strength at two time points and prevalence of sarcopenia at one time point in a subset of participants. Data were analyzed using linear mixed models or multinomial logistic regression models with multivariable adjustment. We found that higher FRAP score was associated with higher FFMI (0.091 kg/m² per standard deviation (SD) higher FRAP score, 95% CI 0.031; 0.150), lower AGR (−0.028, 95% CI −0.053; −0.003), higher BMI (0.115, 95% CI 0.020; 0.209) and lower BF% (−0.223, 95% CI −0.383; −0.064) across follow-up after multivariable adjustment. FRAP score was not associated with hand grip strength or sarcopenia. Additional adjustment for adherence to dietary guidelines and exclusion of individuals with comorbid disease at baseline did not change our results. In conclusion, dietary intake of antioxidants may positively affect the amount of lean mass and overall body composition among the middle-aged and elderly.

Dietary Total Antioxidant Capacity and Risk of Non-Alcoholic Fatty Liver Disease: A Case-Control Study

BACKGROUND

Dietary total antioxidant capacity (DTAC) has been proposed as a tool for assessing the intake of antioxidants. This study aimed to assess whether a relationship exists between dietary total antioxidant capacity (TAC) and the odds of NAFLD.

STUDY DESIGN

A case-control study.

METHODS

In this age-and sex-matched case-control study in 2019, patients with NAFLD and healthy controls were recruited from a hospital clinic. All participants completed a validated 168-item food frequency questionnaire, the results of which were subsequently used to generate dietary TAC. Oxygen radical absorbance capacity values were used to calculate dietary TAC.

RESULTS

Altogether, 225 patients with NAFLD and 450 healthy controls were enrolled. Participants with NAFLD had a higher mean weight, BMI, energy (P<0.050), and lower physical activity and DTAC scores (P<0.050) than the control group. In an adjusted model, participants who were in the highest quartile of dietary TAC had a lower risk of NAFLD (odds ratio 0.78, 95% CI: 0.67, 0.91).

CONCLUSION

A high DTAC was related to a decreased risk of NAFLD. Suggest the intake of a diet with high antioxidant capacity is significant at preventing NAFLD. Increasingly itemized investigations in design of randomized control trials require to reveal more insight into these results.

The interaction between dietary Non-Enzymatic Antioxidant Capacity (NEAC) with variants of Melanocortin-4 receptor (MC4R) 18q21.23-rs17782313 locus on hypothalamic hormones and cardio-metabolic risk factors in obese individuals from Iran

Background: In the current study, we aimed to evaluate the interaction between dietary Non-Enzymatic Antioxidant Capacity (NEAC) and rs17782313 polymorphism on hypothalamic hormones and cardio-metabolic risk factors. Methods: A total of 287 subjects (aged 20-50 years, 147 males and 140 females) enrolled in the cross-sectional study. Dietary NEAC was assessed using databases of NEAC measurements compiled from outcomes for three different analyses: oxygen radical absorbance capacity (ORAC), ferric reducing-antioxidant power (FRAP), and total radical-trapping antioxidant parameter (TRAP) and genotyping for the near MC4R rs17782313 was carried out by Polymerase chain reaction-restriction fragments length polymorphism (PCR-RFLP) method. Results: The significant interactions were found between adherence to the dietary NEAC and MC4R rs17782313 in relation to high-density lipoprotein-cholesterol (HDL-C), glucose, α-melanocyte stimulating hormone (α-MSH), insulin and quantitative insulin sensitivity check index (QUICKI) (P _Interaction = 0.03, 0.01, 0.04, 0.04 and 0.04, respectively). In homozygous subjects for the minor allele, the serum insulin level and QUICKI in participants with the highest adherence to TRAP were significantly higher than those with the lowest adherence (p < 0.001). There was a significant inverse association between high ORAC score and risk of metabolic syndrome even after adjusting for potential confounders (OR: 0.33; 95%CI:0.13-0.81) and also a significant inverse association between high NEAC (ORAC, FRAP and TRAP assays) score and high triglyceride (TG) level was found in obese adults. Conclusion: In conclusion, our study found for the first time that the NEAC significantly interacts with the rs17782313 genotypes to influence several metabolic risk factors in obesity.

Energy-dense nutrient-poor snacks and risk of non-alcoholic fattyliver disease: a case-control study in Iran

OBJECTIVE

The purpose of the present study was to determine the association between energy-dense nutrient-poor snacks intake and the risk of non-alcoholic fatty liver disease (NAFLD) in Iranian adults. For this purpose, a total of 143 cases with a newly confirmed diagnosis of NAFLD and 471 controls free of the disease were studied. Dietary intake was assessed using a food frequency questionnaire.

RESULTS

The percentage of calories from total energy-dense nutrient-poor snacks was 6.08% and 5.04%, in patients and controls, respectively (P = 0.036). Compared with subjects in the lowest quartile of total energy-dense nutrient-poor snacks intake, the risk of NAFLD for those in the top quartile of consumption increased by about two times, in both crude (OR: 1.94; 95% CIs 1.16-3.26; P for trend = 0.015) and adjusted (OR: 2.27; 95%CIs 1.19-4.31; P for trend = 0.001) models. The relative odds of NAFLD increased significantly in the fourth quartile of dietary cake and biscuit (OR: 1.21, P for trend = 0.037) and soft drinks (OR: 1.64, P for trend = 0.005) intake compared with the lowest corresponding quartiles, after adjustment for age, sex, body mass index, physical activity, alcohol, energy intake. Our results indicate that there might be a moderate positive association between energy-dense nutrient-poor snacks intake and risk of NAFLD.

Dietary total antioxidant capacity significantly interacts with 6-P21 rs2010963 gene polymorphisms in terms of cardio-metabolic risk factors in patients with metabolic syndrome

OBJECTIVE

Gene- nutrient interaction might possibly be involved in the pathogenesis of metabolic syndrome and its components. In the current report, the association between antioxidant potential of the diet with 6P21 rs2010963 gene polymorphism in patients with metabolic syndrome has been evaluated. Two hundred fifty-four patients with metabolic syndrome were enrolled. Total dietary antioxidant capacity (TAC) has been estimated and anthropometric assessments were assessed. Biochemical assays including serum glucose, matrix metalloproteinase-3, liver enzymes and lipid profiles were also assessed. Polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) method was used for determination of 6P21 rs2010963 polymorphism.

RESULTS

Dietary vitamin E score was significantly higher in GC genotype compared with other genotypes (P = 0.035). Patients in CC genotype of 6P21 rs2010963 had significantly higher body mass index (BMI), fasting blood sugar and liver enzymes (P < 0.05). Being in the higher dietary TAC scores was also associated with lower liver enzymes. The interaction between 6P21 rs2010963 and dietary TAC significantly affected BMI, FBS and diastolic blood pressure (P < 0.05). According to our findings the CC genotype of 6P21 rs2010963 could be considered as the possible risk factor for obesity and metabolic disorders among patients with metabolic syndrome.

An evaluation of randomized controlled trials on nutraceuticals containing traditional Chinese medicines for diabetes management: a systematic review

BACKGROUND

Nutraceuticals containing traditional Chinese medicine (TCM) are promoted for use in the management of diabetes. The evidence to support such use is largely unknown. This study aimed to summarise and evaluate the literature reporting the results of randomized controlled trials (RCTs) investigating the effects of nutraceuticals in people living with diabetes.

METHODS

Literature from four electronic databases (PubMed, Scopus, CINAHL and Web of Science) was searched following PRISMA guidelines to yield RCT publications on nutraceutical for diabetes management published since 2009. The quality of reporting was assessed using the CONSORT 2010 checklist statement. Risk-of-bias for each study was assessed using the Cochrane risk of bias tool.

RESULTS

Out of 1978 records identified in the initial search, 24 randomized, double/triple-blinded, controlled trials that investigated the effect of nutraceuticals covering 17 different TCM herbs for diabetes management were selected. Participants included people who were diabetic (n = 16), pre-diabetic (n = 3) or predisposed to diabetes (n = 5). Sample sizes ranged between 23 and 117 for 2 arms, or 99-165 for 3 arms. Comparisons were made against placebo (n = 22), conventional medicine (n = 1), or regular diet (n = 1) for a duration between 4 and 24 weeks. All but one study tested the effect on fasting blood glucose levels (n = 23) or glycated haemoglobin levels (n = 18), and/or postprandial 2-h blood glucose levels (n = 4) as the primary outcomes. Nineteen studies reported some statistically significant reductions in the respective measures while 5 studies showed no effect on primary or secondary outcomes. None of the included studies met all the criteria for the CONSORT guidelines. Incomplete reporting about randomization and blinding, and a lack of ancillary analyses to explore other influential factors and potential harms associated with the use were repeatedly noted. Based on the Cochrane risk-of-bias tool, 19 studies were deemed to have a high risk of bias mainly attributed to sponsor bias.

CONCLUSIONS

There is some evidence to suggest positive clinical outcomes in response to the administration of a range of nutraceuticals containing TCM in the management of diabetes. However, these results must be interpreted with caution due to the overall low quality of the trials.

Association of dietary total antioxidant capacity to anthropometry in healthy women: A cross-sectional study

OBJECTIVES

Reactive oxygen species level is a fundamental component in the pathogenesis of obesity that might be reduced by dietary antioxidants. Measurement of dietary total antioxidant capacity (DTAC) is regarded as a new holistic dietary index. Given the limited research on DTAC, the aim of this study was to examine the association of DTAC with obesity-related features in women.

METHODS

The present cross-sectional study included 627 female participants. Data on dietary intake were assessed using a validated food frequency questionnaire. DTAC was estimated through total reactive antioxidant potential (TRAP), Trolox equivalent antioxidant capacity (TEAC), and ferric reducing ability of plasma (FRAP). Anthropometric parameters (body mass index and waist circumference), were investigated using standard methods.

RESULTS

After adjustment for possible covariates, both TRAP and TEAC were significantly positively associated with obesity (TRAP: OR, 1.65; 95% confidence interval [CI], 1.04-2.63; P_trend, 0.03; TEAC: OR, 1.63; 95% CI, 1.01-2.63; P_trend, 0.04). However, there was no association between FRAP and obesity (OR_, 1.11; 95% CI, 0.64-1.93; P_trend, 0.68). Moreover, no relationship was found between different DTAC indices and waist circumference (TRAP: OR, 1.13; 95% CI, 0.70-1.80; P_trend, 0.60; TEAC: OR, 1.04; 95% CI, 0.64-1.69; P_trend, 0.87; FRAP: OR, 0.86; 95% CI, 0.49-1.51; P_trend, 0.62).

CONCLUSION

Women with higher DTAC scores had higher risk for obesity. No association was found between DTAC and waist circumference.

The importance of antioxidants and place in today's scientific and technological studies

Antioxidants have become scientifically interesting compounds due to their many benefits such as anti-aging and anti-inflammatory. Today, it is still used in many areas. In food technology, antioxidants are added to many foodstuffs in order to enrich the foods and eliminate the problems. Therefore, studies to determine the antioxidant activities of natural foods and their components are also continuing rapidly. Antioxidants have also been replaced in the encapsulation studies used for the preservation and stabilization of food components. Of course, preservation of foods is as important as their production. The latest packaging techniques for food preservation are edible films and coatings. The protective function of edible films and coatings can be improved by the addition of antioxidants. Unlike these, studies on plants and animals have been investigated in vivo in terms of how the antioxidant activity changes as a result of metabolic activities. The role of antioxidant enzymes in these studies is quite large. Many results have been found for the elimination of diseases by either in vivo or in vitro studies regarding antioxidants. Thus, the importance of antioxidants increased with the use in pharmacology, cosmetics and medicine. In this study, we tried to bring a current perspective to antioxidants played an active role in many fields by combining the technological applications and scientific studies of antioxidants. In order to further customize the issue, we have done this especially for the food and health field and we have tried to emphasize the importance of antioxidants in this way.

High dietary total antioxidant capacity is associated with a reduced risk of hypertension in French women

Background

Although there is evidence for a reduced risk of hypertension associated with fruit and vegetable consumption, the relationship between the total antioxidant capacity of the diet (TAC) and the risk of hypertension has not been previously examined. We aimed to evaluate that association in the large E3N French prospective cohort of women.

Methods

Dietary TAC was estimated using total radical-trapping ability parameter (TRAP) assay food values; self-reported incident hypertension cases were validated. Cox regression models were adjusted for conventional risk factors, body mass index, physical activity, energy, sodium, magnesium, omega-3 fatty acids, and alcohol.

Results

After an average 12.7 years of follow up, there were 9350 incident cases of hypertension among 40,576 women. Dietary TAC was inversely associated with the risk of hypertension with a 15% lower risk of hypertension in those in the fifth vs. first quintile (HR_Q5 0.85 [CI 95% 0.74; 0.95] p-trend 0.03) An inverse dose-effect relationship was observed for dietary TAC excluding coffee (HR_Q5 0.85 [CI 95% 0.74; 0.95], p-trend 0.0008), while for dietary TAC from coffee, only the highest quintile was inversely associated with risk (HR_Q5 0.86 [0.75, 0.97], p-trend 0.20). In a fully partitioned model with major dietary TAC contributors, TAC from fruit/vegetables, wine, and miscellaneous sources was inversely associated with risk, while associations with TAC from coffee, tea, and chocolate were not statistically significant.

Conclusions

In a large prospective cohort, the risk of incident hypertension in women was inversely associated with the antioxidant capacity of the diet, suggesting that promoting a diet naturally rich in antioxidants might help prevent the development of hypertension.

Electronic supplementary material

The online version of this article (10.1186/s12937-019-0456-0) contains supplementary material, which is available to authorized users.

Dietary and Biochemical Characteristics Associated with Normal-Weight Obesity

Background: Inflammation and oxidative stress have been reported to be higher in subjects with normal weight obesity (NWO) syndrome [normal body mass index (BMI) (<25 kg/m²) but excessive body fat (for women ≥ 30% and for men ≥ 20%) according to World Health Organization (WHO) definitions]; however, it is unclear whether this is due to inadequate dietary antioxidant intake or the pathophysiology of NWO. The aim of present study was to assess the association between dietary factors and body antioxidant status with NWO syndrome in male university students. Methods: This study was a case-control study carried out on ninety age-matched male university students [30 normal weights (NW), 30 NWO and 30 overweight-obese (OB)]. A validated food frequency questionnaire (98 items) and 3-day 24-h recalls were used for dietary assessment. Total antioxidant capacity (TAC) of diet and serum and high-sensitive C-reactive protein (hs-CRP) concentrations were also measured. Results: Dietary intake of fruits (frequency factor (FF) = 2.3 vs 2.9, p < 0.05), legumes (FF = 0.7 vs 1.3, p < 0.01), nuts and seeds (FF = 0.4 vs 0.8, p < 0.05), beta-cryptoxanthin (p < 0.05), lycopene (p < 0.05) and serum TAC levels (p < 0.01) were significantly lower in NWO compared to the NW group. No significant differences in these parameters were observed between NWO and OB group. A significant negative correlation was observed between serum TAC levels and BMI (r = -0.57, p < 0.001) and body fat percent (r = -0.52, p < 0.001). Conclusions: This study shows that NWO male subjects consume lower amounts of dietary antioxidants and share the same low body antioxidant status as obese individuals, although they appear lean.

Dietary Total Antioxidant Capacity and the Risk of Chronic Kidney Disease in Patients With Type 2 Diabetes: A Nested Case-Control Study in the Tehran Lipid Glucose Study

OBJECTIVE

Dietary total antioxidant capacity (DTAC) has been hypothesized as being involved in health promotion and disease prevention. However, data about the association of the DTAC (as estimated by ferric reducing antioxidant power) with diabetes chronic complications are scarce. Therefore, the aim of this study was to determine the associations between the DTAC and chronic kidney disease (CKD) risk in subjects with type 2 diabetic.

METHODS

The present case-control study consisted of 210 (102 cases and 108 controls) patients with type 2 diabetic who were participants of the phase 5 Tehran Lipid and Glucose Study and were classified based on their CKD status. DTAC was estimated based on the ferric reducing antioxidant power of selected foods. Dietary intake, sociodemographic data, medical history, and anthropometric measurements were collected from participants using a validated questionnaire.

RESULTS

The mean DTAC value, as well as total calorie intake, did not show significant differences between cases and controls.

CONCLUSION

No significant association was found between DTAC and CKD in patients with type 2 diabetic. Further studies are needed to confirm the effects of DTAC on the risk of CKD.

Dietary and Lifestyle Risk Factors and Metabolic Syndrome: Literature Review

Metabolic syndrome (MetS) is considered a threat to public health due to its rapid growing prevalence worldwide. MetS can result from interrelated metabolic abnormalities including insulin resistance (IR), hypertension, dyslipidemia, and abdominal adiposity. Although the pathogenesis of this syndrome is not distinctly understood, it is strongly influenced by multiple genetic variations that interact with many environmental factors such as positive family history of MetS, adherence to unhealthy dietary patterns, low physical activity and smoking and that explain the variations in the prevalence of the MetS within and across populations. All of these factors were found to be associated with IR, obesity, and triglycerides elevation which therefore increase the risk of the MetS Several studies highlighted the effective preventive approach includes lifestyle changes, primarily losing weight, adopting healthy diet, and practicing exercise. All of the mentioned factors can reduce the risk of MetS.