The association between metabolic syndrome and insulin resistance with risk of cardiovascular events in different states of cardiovascular health status.

AIMS/INTRODUCTION: The aim was to examine the joint effect of metabolic syndrome (MetS) and insulin resistance (IR) with ideal cardiovascular health (iCVH) status on incident cardiovascular diseases (CVDs). MATERIALS AND METHODS: The study included 6,240 Iranian adults ≥30 years, free of prior cardiovascular disease. Ideal cardiovascular health was determined based on American Heart Association's Life Simple 7. Metabolic syndrome was defined according to the Joint Interim Statement Criteria, and insulin resistance was defined as HOMA-IR ≥1.85 in women and ≥2.17 in men. Multivariable Cox proportional hazard ratios (HRs) were applied to examine the impact of metabolic syndrome, and insulin resistance at various levels of iCVH status. RESULTS: During the median follow-up of 14.0 years, 909 cases of cardiovascular disease occurred. Metabolic syndrome and insulin resistance were significantly associated with incident cardiovascular disease events. In the poor and intermediate status, metabolic syndrome increased cardiovascular disease events with HRs of 1.83 and 1.57, respectively; the corresponding values for insulin resistance in the mentioned categories were 1.91 and 1.25, respectively (P values < 0.05). In the intermediate and poor iCVH status, hypertriglyceridemia was linked to a 40% and 35% higher risk of cardiovascular disease, the corresponding values for low HDL-C was 20% and 60%, respectively (P values < 0.05). Although adding metabolic syndrome, its dyslipidemia and insulin resistance to iCVH status in both poor and intermediate status significantly improve the prediction of cardiovascular disease using net reclassification improvement (P values < 0.05), the value of C-index did not change. CONCLUSIONS: Metabolic syndrome and the dyslipidemia component had a negligible but significant improvement in the prediction of cardiovascular disease among individuals with non-optimal iCVH status.

Association between dietary antioxidants intake and the risk of type 2 diabetes mellitus in a prospective cohort study: Tehran Lipid and Glucose Study.

The present prospective cohort study aimed to determine whether dietary antioxidants were associated with incident type 2 diabetes mellitus (T2DM). Another objective was to find out whether such associations could be modified by the BMI status. A total of 2188 Tehranian adults aged 21-84 years, free of T2DM with the validated FFQ, was entered in the study. Multivariable Cox proportional hazards models adjusting for confounders were used to assess the association between dietary antioxidants and incident T2DM in total population, as well as in subjects with various BMI statuses. During 8·9 (8·1-9·6) years of follow-up, dietary vitamin E significantly decreased the incident T2DM, after adjustment for confounders. However, other dietary antioxidants were not shown to be significantly associated with incident T2DM. The interaction between dietary vitamin E, Mg and BMI status was found to influence the risk of T2DM (Pfor interaction < 0·05). After stratification of subjects based on BMI status, it was found that vitamin E and Mg decreased the risk of T2DM only among normal-weight individual. Also, an inverse association was found among dietary vitamin C, dietary Zn and the risk of T2DM in individuals with normal weight but not in overweight and obese individuals; however, the interaction test tended to be significant for these dietary variables. Dietary antioxidants including vitamin E, vitamin C, Zn and Mg when accompanied by healthy weight, may bring benefits to the prevention of T2DM.

Effect of weight change on the association between overall and source of carbohydrate intake and risk of metabolic syndrome: Tehran lipid and glucose study.

BACKGROUND: In this prospective cohort study, we aimed to evaluate the association between dietary carbohydrates, whole grains, refined grains, and simple sugar with the risk of metabolic syndrome (MetS) and assess the effect of weight change on these associations. METHODS: This study was conducted within the framework of the Tehran Lipid and Glucose Study (TLGS). We included 1915 healthy participants with complete demographic, anthropometric and dietary measurements, among whom 591 developed MetS during 8.9 years of follow-up. Intake of dietary carbohydrates, whole grains, refined grains, and simple sugar was assessed with a validated semi-quantitative food frequency questionnaire. Multivariable adjusted Cox regression was used to estimate hazard ratios (HRs) for MetS events across tertiles of dietary variables. Using joint classification, the effect of weight change on the association between dietary variables and risk of MetS was assessed by Cox regression. RESULTS: Carbohydrate intake was not associated with the risk of MetS in multivariable-adjusted models. Whole grains intake was inversely associated with the risk of MetS (HR: 0.78, CI: 0.63-0.98), while this association disappeared after adjustment for weight change. The risk of MetS increased by 11% (1.11, 1.09-1.14) for each 3% energy increment from simple sugar, and by 5% (1.05, 1.03-1.08) for each 1 serving/day increment in refined grains. Consumption of refined grains increased the risk of MetS; an effect modification of this association was found by weight change. Among subjects with weight loss, intake of refined grains < median intake decreased the risk of MetS (0.59, 0.41-0.87). However, consumption of refined grains ≥ median intake increased the risk of MetS in individuals with weight gain (1.47, 1.08-2.01). Simple sugar was positively associated with an increased risk of MetS, after adjustment for weight change (3.00, 2.37-3.82). In joint classification, intake of simple sugar greater than median intake increased the risk of MetS, independent of weight change. CONCLUSION: Our findings suggest an effect modification by weight change on the association between carbohydrates, and refined grains intake and the risk of MetS. Weight loss along with lower consumption of carbohydrates, and refined grains reduced the risk of MetS. However, simple sugar intake, regardless of weight change, was associated with an increased risk of MetS.

Relation of dietary insulin index and dietary insulin load to metabolic syndrome depending on the lifestyle factors: Tehran lipid and glucose study.

AIM: The hypothesis of the effect of the insulinogenic effects of diet on the development of cardiovascular diseases has been proposed, but the findings of previous studies are very contradictory. We investigated the association between dietary insulin index (DII) and dietary insulin load (DIL), and metabolic syndrome (MetS) risk. Another objective was to examine the extent to which lifestyle (physical activity, smoking status, and weight change) and sex influence the relationship between DII, DIL, and MetS risk. MATERIALS AND METHODS: We followed 1915 participants in the Tehran Lipid and Glucose Study. DIL and DII were calculated based on a validated food frequency questionnaire. Weight change was measured, and participants were categorized into > 3% weight loss, weight stable (± 3%), and > 3% weight gain. By joint classification, the association between DII and DIL (< median and ≥ median) and risk of MetS was assessed according to weight change, sex, physical activity levels, and smoking status. Cox proportional hazards models were used to estimate the HRs (95% CI), adjusting for potential confounders. RESULTS: During 8.9 years of follow-up, among 1915 participants, we documented 591 new cases of MetS. DII and DIL were not associated with MetS risk in the crude and adjusted models. However, DIL and DII were associated with weight gain (≥ 3%). In the crude model, DIL and DII were associated with a higher risk of weight gain [HR: 1.74: 95% CI 1.50-2.03, and 1.70 (1.46-1.98), respectively]. These associations remained significant after further adjustment for confounders. The HRs were 1.61 (1.35-1.92) for DIL and 1.64 (1.39-1.93) for DII. Among men, women, participants with low physical activity levels, and smokers, the risk of MetS, independent of DIL and DII, only increased in a participant with weight gain. In women with weight stability, DIL and DII, higher than the median, were positively associated with MetS risk. CONCLUSION: Our findings suggest that the association between MetS risk and a hyperinsulinemic diet depended on weight change.

Effect of TCF7L2 on the relationship between lifestyle factors and glycemic parameters: a systematic review.

BACKGROUND: Among candidate genes related to type 2 diabetes (T2DM), one of the strongest genes is Transcription factor 7 like 2 (TCF7L2), regarding the Genome-Wide Association Studies. We aimed to conduct a systematic review of the literature on the modification effect of TCF7L2 on the relation between glycemic parameters and lifestyle factors. METHODS: A systematic literature search was done for relevant publications using electronic databases, including PubMed, EMBASE, Scopus, and Web of Science, from January 1, 2000, to November 2, 2021. RESULTS: Thirty-eight studies (16 observational studies, six meal test trials, and 16 randomized controlled trials (RCTs)) were included. Most observational studies had been conducted on participants with non-diabetes showing that TCF7L2 modified the association between diet (fatty acids and fiber) and insulin resistance. In addition, findings from meal test trials showed that, compared to non-risk-allele carriers, consumption of meals with different percentages of total dietary fat in healthy risk-allele carriers increased glucose concentrations and impaired insulin sensitivity. However, ten RCTs, with intervention periods of less than ten weeks and more than one year, showed that TCF7L2 did not modify glycemic parameters in response to a dietary intervention involving different macronutrients. However, two weight loss dietary RCTs with more than 1-year duration showed that serum glucose and insulin levels decreased and insulin resistance improved in non-risk allele subjects with overweight/obesity. Regarding artichoke extract supplementation (ALE), two RCTs observed that ALE supplementation significantly decreased insulin concentration and improved insulin resistance in the TT genotype of the rs7903146 variant of TCF7L2. In addition, four studies suggested that physical activity levels and smoking status modified the association between TCF7L2 and glycemic parameters. However, three studies observed no effect of TCF7L2 on glycemic parameters in participants with different levels of physical activity and smoking status. CONCLUSION: The modification effects of TCF7L2 on the relation between the lifestyle factors (diet, physical activity, and smoking status) and glycemic parameters were contradictory. PROSPERO REGISTRATION NUMBER: CRD42020196327.

Effect of dietary approaches to stop hypertension (DASH) diet, high in animal or plant protein on cardiometabolic risk factors in obese metabolic syndrome patients: A randomized clinical trial.

AIMS: This study aimed to investigate the effect of replacing plant proteins with animal proteins in the dietary approaches to stop hypertension (DASH) diet on cardiometabolic risk factors in obese metabolic syndrome participants. METHODS: In this double-blind randomized controlled clinical trial, 90 obese patients with metabolic syndrome, aged 30-70 years were randomly allocated into the DASH diet based on plant or animal proteins for 8 weeks. Fasting blood samples were collected to assess the biochemical markers. Also, blood pressure, weight, and waist circumference (WC) were measured at the beginning and end of the trial. RESULTS: The participants in both groups experienced significant reductions in the fasting plasma glucose (FPG), systolic blood pressure (SBP) and diastolic blood pressure (DBP), triglyceride (TG) concentrations, weight and WC. However the reduction in FPG and SBP was higher in the plant-based DASH group, compared to the animal-based DASH group, after adjustment for weight change. No significant changes were found within or between groups with regard to total cholesterol, LDL-C, HDL-C. CONCLUSIONS: Substituting plant proteins with animal proteins in the DASH diet improves FPG and SBP in obese individuals with metabolic syndrome, independent of weight change. IRCT registration number: IRCT20090203001640N16.

Ideal cardiovascular health status and risk of cardiovascular disease and all-cause mortality: over a decade of follow-up in the Tehran lipid and glucose study.

Objective: To quantify the association between ideal cardiovascular health (CVH) metrics and incident cardiovascular disease (CVD) including different subtypes [coronary heart disease (CHD), stroke, and sudden death], and all-cause mortality in an Iranian population. Methods: The study population included 6,388 participants (2,726 men) aged 48.0 ± 12.4 years free of CVD at baseline. We utilized the American Heart Association's 2020 impact target criteria of ideal, intermediate, and poor CVH. The multivariate Cox proportional Hazard model, adjusted for age, sex, educational level, marital status, and family history of CVD, was applied to estimate the hazard ratio (HR) of outcomes per one additional metric of ideal CVH metrics. Furthermore, the risk was also calculated for ideal and intermediate categories considering poor category as a reference. Results: During the median follow-up of 11.26 years, 692 CVD, 589 CHD, 130 stroke, 111 sudden death, and 519 all-cause mortality events were reported. All of the individual ideal CVH metrics were independent predictors except intermediate physical activity level for CVD, BMI < 25 kg/m2, and intermediate physical activity for all-cause mortality. Each additional metrics of ideal CVH decreased the risk by 31 (0.69, 0.65-0.73) for CVD, 32 (0.68, 0.64-0.73) for CHD, 31 (0.69, 0.60-0.80) for stroke, 25 (0.75, 0.64-0.88) for sudden death, and 13% (0.87, 0.81-0.93) for all-cause mortality events. Moreover, intermediate and ideal categories of CVH metrics were associated with lower risk for different CVD outcomes, i.e., 44 (0.56, 0.48-0.65) and 76% (0.24, 0.17-0.35) for CVD; 43 (0.57, 0.47-0.67) and 75% (0.25, 0.16-0.37) for CHD, 58 (0.42, 0.29-0.61) and 86% (0.14, 0.04-0.44) for stroke; 56 (0.44, 0.29-0.66) and 55% (0.45, 0.21-0.99) for sudden death; and 25 (0.75, 0.62-0.90) and 46% (0.54, 0.37-0.80) for all-cause mortality events, respectively. We also assessed the impact of changes in ideal CVH status from phase III to phase IV (2008-2011) on CVD events among 5,666 participants. Accordingly, compared to those remaining in the poor category, all of the changes in ideal CVH categories showed a lower risk for CVD events. Conclusion: Among the Iranian population, meeting higher ideal CVH metrics is associated with a lower risk of different CVD events and mortality outcomes.

A plant-based dietary score and attention deficit/hyperactivity disorder in Iranian children: A case-control study.

OBJECTIVE: Attention-deficit hyperactivity disorder (ADHD) is the most prevalent neurodevelopmental disorder with a prevalence of 5 % among children and adolescents worldwide. Plant foods have a protective effect against inflammation and oxidative stress which both are involved in psychiatric disorders pathophysiology including ADHD. Accordingly, we investigated the association between plant-based diet (PDI) and ADHD. METHODS: This case-control study was conducted on 345children and adolescents 7-13 years old in Yazd, Iran. Subjects were categorized into the case (n = 113) and control groups (n = 232) based on matching age and sex. To diagnose ADHD, the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSMIV-TR) was used. Food frequency questionnaire was used to measure food intake. The association of PDI with ADHD was examined by logistic regression. RESULTS: Children in the highest quartile of PDI compared to the lowest quartile had a higher energy and macronutrient intake, calcium, zinc, iron, vitamin B12, B6, and folic acid. After adjusting for potential confounders, a significant decreasing trend in the odds of ADHD across increasing quartiles of the PDI (P-trend = 0.001) was observed. In addition, children in the fourth quartile of PDI had 68 % lower odds of ADHD than the first quartile. This association remained significant after further adjustment for BMI (OR: 0.32;95 % CI: 0.13-0.79; P for trend: 0.001). CONCLUSION: We found that PDI is associated with lower risk of ADHD in children. Cohort and clinical studies are necessary to approve our results.

Effect of legumes in energy reduced dietary approaches to stop hypertension (DASH) diet on blood pressure among overweight and obese type 2 diabetic patients: a randomized controlled trial.

BACKGROUND: This study aimed to investigate the effects of legumes in dietary approaches to stop hypertension (DASH) on blood pressure and urinary sodium and potassium in participants with type 2 diabetes. We further investigated whether changes in individual dietary food groups in the DASH diet contribute to blood pressure. METHODS: Participants were randomized to the traditional DASH diet (n = 150) or the legume-based DASH diet (n = 150). Blood pressure and urinary sodium and potassium were measured at baseline and after 16-week interventions. An intention-to-treat approach with multiple imputations of missing data was applied. The restricted cubic spline (RCS) was applied to assess the linearity and explore the shape of the relationship between the changes in food groups and systolic blood pressure (SBP) in the two intervention groups. RESULTS: A reduction in SBP and urinary sodium was observed at week 16 in both dietary interventions, and this reduction was more significant in the legume-based DASH diet, than in the DASH diet. In the legume-based DASH diet, SBP decreased with the legume intake of more than 95.8 g/day (P nonlinear < 0.001). The multivariable RCS analysis showed a U-shaped relationship of refined grains, an L-shaped relationship of fruits, and a linear relationship of sweet, energy, sodium and vegetables intake with SBP. CONCLUSIONS: The DASH diet, enriched in legumes, could improve SBP in participants with type 2 diabetes. In DASH diet, the balance of consumption of refined grains and fruits along with higher vegetable consumption and lower sweet, sodium and energy intake reduced the SBP. TRIAL REGISTRATION: IRCT20090203001640N17.

The effect of TCF7L2 polymorphisms on inflammatory markers after 16 weeks of legume-based dietary approach to stop hypertension (DASH) diet versus a standard DASH diet: a randomised controlled trial.

BACKGROUNDS: This randomized controlled trial aimed to investigate the effects of replacing red meat with legumes in the dietary approach to stop hypertension (DASH) diet on inflammatory markers over 16 weeks in overweight and obese individuals with type 2 diabetes. Also, the modulatory effects of TCF7L2 rs7903146 variant on this effect were assessed. METHODS: In this trial, 300 participants with type 2 diabetes, aged 30-65 years with an identified TCF7L2 rs7903146 genotype, were studied. The participants were randomly assigned to the DASH diet or the legume-based DASH diet over 16 weeks. In the DASH diet group, the participants were instructed to follow the standard DASH diet. The legume-based DASH diet was similar to the standard DASH diet, with the exception that one serving of red meat was replaced with one serving of legumes at least five days a week. At the beginning of the study and 16-week follow-up, venous blood samples were collected from all participants who fasted for 12-14 h overnight. The serum concentration of High-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) was measured using an enzyme-linked immunosorbent assay (ELISA) kit. Also, the serum malondialdehyde (MDA) concentration was assessed based on a colorimetric method using a commercial kit. The primary outcome was the difference in hs-CRP changes between the diets. A secondary outcomes was the difference in IL-6, TNF-α, and MDA between the groups among total population and based on TCF7L2 rs7903146 risk allele (CT + TT) and non-risk allele (CC) separately. RESULTS: The hs-CRP level reduced in the legume-based DASH diet group as compared to the DASH diet group in the 16-week follow-up group. The levels of TNF-α, IL-6, and MDA reduced after the legume-based DASH diet relative to the DASH diet. Reduction of inflammatory markers was observed in both carriers of rs7903146 risk allele and non-risk allele. CONCLUSIONS: Substituting one serving of red meat with one serving of legumes in DASH diet, at least five days a week, could improve the hs-CRP, TNF-α, IL-6, and MDA in participants with type 2 diabetes regardless of having rs7903146 risk or non-risk allele. Trial registration IRCT, IRCT20090203001640N17.

Improvement of glycemic indices by a hypocaloric legume-based DASH diet in adults with type 2 diabetes: a randomized controlled trial.

PURPOSE: The current study aimed to investigate the effects of legumes inclusion in the hypocaloric dietary approaches to stop hypertension (DASH) diet on fasting plasma glucose (FPG) and cardiometabolic risk factors in overweight and obese patients with type 2 diabetes over 16 weeks. Also, the modulatory effects of rs7903146 variant in the transcription factor 7 like 2 (TCF7L2) gene that is associated with the risk of diabetes, were assessed on these cardiometabolic risk factors. METHODS: This study was a randomized controlled trial. Three-hundred participants, aged 30-65 years, whose TCF7L2 rs7903146 genotype was determined, were studied. The participants were randomly assigned to receive either the hypocaloric DASH diet or a hypocaloric legume-based DASH diet. The primary outcome was the difference in FPG change from baseline until the 16-week follow-up between the two dietary interventions. The secondary outcomes were differences in insulin resistance and lipid profile changes between the dietary intervention diets. RESULTS: A reduction in FPG, insulin, homeostatic model assessment for insulin resistance (HOMA-IR), triglyceride, total cholesterol, and low-density lipoprotein cholesterol (LDL-C) was observed at week 16 in both hypocaloric dietary interventions. Compared to the DASH diet, the legume-based DASH diet decreased the FPG and HOMA-IR. There is no interaction between rs7903146 and intervention diets on glycemic parameters. CONCLUSION: The DASH diet, enrich in legumes, could improve the glycemic parameters in participants with type 2 diabetes, regardless of having rs7903146 risk or non-risk allele. REGISTRATION NUMBER OF CLINICAL TRIAL: Iranian Registry of Clinical Trials (IRCT) (code: IRCT20090203001640N17).

Associations between dietary antioxidant intakes and cardiovascular disease.

Cardiovascular disease (CVD), as the leading cause of death worldwide, is the collective term named for disorders afflicting the blood vessels and heart. Inflammation and enhanced oxidative stress have been shown as fundamental risk factors in the onset and progression of CVD. Chronic inflammatory conditions attenuate blood levels of antioxidants because of the continuous generation of elevated levels of reactive oxygen species (ROS). A sufficient intake of antioxidants is also suggested to beneficially interfere with CVD by quenching ROS. Antioxidant vitamins and minerals, such as vitamins A, E, and C, and zinc may slow the development and progression of CVD. This study aimed at investigating the association between daily consumption of dietary vitamins A, E, and C, and zinc and the incidence of CVD. Eligible adults (n = 5102) aged ≥ 30 years, were selected from the participants of the Tehran lipid and glucose study with an average follow-up of 5.3 years. Dietary intake was assessed using a valid and reliable semi-quantitative food frequency questionnaire. Anthropometrics and biochemical variables were evaluated at baseline and follow-up examinations. Multivariable Cox proportional hazard regression models were used to estimate the development of CVD associated with total intakes of vitamins A, E, and C, and zinc. This study was conducted on 2253 men and 2849 women aged 47.0 ± 11.6 and 45.6 ± 10.5 years, respectively. The main sources of dietary vitamins A, E, and C and zinc were fruits, vegetables, and legumes. Risk of CVD decreased from quartile 1 to quartile 4 for vitamin E intake (HR 1.00, 0.91, 0.77, and 0.57; Ptrend = 0.03). The association between the risk of CVD and quartiles of vitamins A, and C and zinc intake was not statistically significant. Our study suggests an inverse association between vitamin E intake and the risk of CVD, emphasizing the potential protective role of fruit and vegetable in the prevention of CVD.

The protective effects of dietary intake of flavonoids and its subclasses on metabolic syndrome incidence.

This study aimed to evaluate the association between the intake of total flavonoids and flavonoid subclasses and metabolic syndrome (MetS) risk and to assess the modulating effects of lifestyle factors on these associations. A total of 1915 participants from the Tehran Lipid and Glucose Study were followed-up during 2006-2008 and 2016-2018. Their dietary intake was assessed by a food frequency questionnaire at baseline and within three-year intervals afterward. Moreover, the modifying effect of weight gain on the association between total flavonoids and MetS was assessed by Cox regression analysis. Participants in the highest tertile of flavonoid, flavonol, and flavone had a significantly lower MetS risk as compared to those in the lowest tertile. Also, in participants with weight gain <7%, all flavonoid subclasses had a more pronounced risk-reducing effect. Overall, the total flavonoid, flavonol, and flavone reduced the risk of MetS; this association could be modified by weight gain.

The role of different lipid measures for incident hypertension during more than 12-year follow-up: Tehran Lipid and Glucose Study.

The associations of different lipid measures and related indices with incident hypertension during a median follow-up of 12·89 years were examined. Fasting levels of total cholesterol (TC), TAG, HDL-cholesterol and LDL-cholesterol, and related indices (TC/HDL-cholesterol and TAG/HDL-cholesterol) were determined in 7335 Iranian adults (men = 3270) free of hypertension, aged 39·0 (sd 13·2) years. Multivariate Cox proportional hazard regression was applied and lipid parameters were considered either as categorical or continuous variables. During follow-up, 2413 (men = 1126) participants experienced hypertension. Using the first quartile as reference, significant trends were found between quartiles of TAG, HDL-cholesterol, TC/HDL-cholesterol and TAG/HDL-cholesterol in multivariate models; moreover considering these measures as continuous variables, a 1 sd increase in each of these parameters was significantly associated with the risk of incident hypertension; the corresponding hazard ratios and CI were 1·06 (95 % CI 1·02, 1·10), 0·94 (95 % CI 0·89, 0·98), 1·04 (95 % CI 1·01, 1·09) and 1·04 (95 % CI 1·01, 1·07), respectively. The associations between lipid measures and incident hypertension did not change after excluding lipid lowering drug users and those with type 2 diabetes mellitus and these associations were independent of the categories of baseline blood pressure (P for interaction > 0·08). These findings indicate that TAG, TAG/HDL-cholesterol and TC/HDL-cholesterol were independently associated with higher risk, while HDL-cholesterol was associated with lower risk of incident hypertension.

Does weight change modify the association between the consumption of sugar-sweetened beverages and 100% fruit juice and the risk of metabolic syndrome?

BACKGROUND & AIMS: This study aimed to determine the prospective relationship between the consumption of sugar-sweetened beverages (SSBs) and 100% fruit juice and metabolic syndrome (MetS) and to investigate whether weight change can modify this association in a representative sample of the population of Tehran, Iran. METHODS: In this 8.9-year follow-up study, the consumption of SSBs and 100% fruit juice by 1915 individuals, who participated in Tehran Lipid and Glucose Study (TLGS), was examined using a validated food frequency questionnaire. The MetS was defined according to the Joint Interim Statement. Participants were categorized as those who lost weight (≥-2%), those with weight stability (-1.9%-1.9%), and those who gained weight (≥2%). The Cox regression model was used to determine the relationship between the consumption of SSBs and 100% fruit juice and the risk of MetS and weight gain ≥2%. Also, the modifying effect of weight change including weight loss, weight stability and weight gain on the relationship between SSBs and 100% fruit juice consumption and the incidence of MetS was assessed. RESULTS: There was no significant association between the consumption of SSBs and the risk of MetS in the crude model; however, after adjustments for confounders, a significant positive association was found between the consumption of SSBs and the risk of MetS (HR: 1.33; 95% CI: 1.07-1.66). Also, no significant association was observed between the consumption of 100% fruit juice and the risk of MetS in the crude model. However, after adjustments for the potential confounders, 100% fruit juice was inversely associated with the MetS risk (HR: 0.78; 95% CI: 0.63-0.95). The consumption of SSBs and 100% fruit juice was positively associated with weight gain (≥2% during the follow-up). Nevertheless, after adjustments for lifestyle and dietary factors, there was no significant association between the consumption of SSBs and weight gain. On the other hand, the consumption of 100% fruit juice was positively associated with the increased risk of weight gain (HR: 1.41; 95% CI: 1.20-1.65). Among participants with weight loss, the first, second and third tertiles of 100% fruit juice reduced the risk of MetS by 29% (HR: 0.71; 95% CI: 0.51-0.99), 47% (HR: 0.53; 95% CI: 0.37-0.75) and 35% (HR: 0.65; 95% CI: 0.46-0.92), respectively. CONCLUSION: Although 100% fruit juice reduced the risk of MetS, its consumption must be limited due to its positive effect on weight gain. On the other hand, the consumption of 100% fruit juice reduced the risk of MetS, depending on the individual's weight change. Also, high consumption of SSBs was associated with the incidence of MetS.

Socioeconomic status and lifestyle factors modifies the association between snack foods intake and incidence of metabolic syndrome.

BACKGROUND: Intake of snack foods has been previously associated with an elevated risk of chronic disease; however, studies on snack foods and metabolic syndrome (MetS) while considering the modifying effect of socioeconomic status (SES) and lifestyle factors on this association are lacking. We aimed to investigate the association between snack foods intake and the MetS risk, and the mediatory effects of SES and lifestyle factors on the forenamed association among adults who participated in the Tehran Lipid and Glucose Study (2006-2018). METHODS: This is a prospective study of 1915 participants (male, 40.5%), aged 19-74 year who were free of MetS at baseline. Dietary intakes were gathered using a validated, semi-quantitative food frequency questionnaire at baseline (2006-2008), and with 3-year intervals afterwards. Alternative approach was used for snack foods from all available questionnaires during follow-up. Snack foods were divided into 4 categories, including total snacks, biscuits and cakes, candies and chocolate, and salty snacks. Total snack foods intake and its subgroup (serving/week) were modeled as tertiles. MetS was diagnosed according to the Joint Interim Statement criteria. Physical activity level (PAL) categorized as low/medium and high levels. Information regarding smoking (Smoker/Non-smoker), education (higher/lower education), and occupation (employed/non-employed) was gathered using questionnaire. The Cox regression was used, regarding interaction between snack foods, SES, and PAL on the MetS risk. RESULTS: A total of 591 incident MetS cases were diagnosed during 8.9 years of follow-up. The median total snack foods intake was 5.2 serving/week (IQR: 3.0-9.1). Total snack foods intake was positively associated with the MetS risk after adjusting for potential confounders (adjusted for age and gender, energy intake, total fiber intake, smoking status, PAL, education levels, family history of diabetes, family history of CVD events, and BMI). After adjustment for confounders, among snacks' subgroups, candies and chocolate intake was positively associated with MetS risk. Moreover, among lower-educated and non-employed participants, candies and chocolate intake was positively associated with the MetS risk, by 38 and 43% respectively. Stratification based on PAL resulted a positive association between intake of total snack foods and candies and chocolates and risk of MetS among participants with low PAL. CONCLUSION: Snack foods, especially candies and chocolate, increased the risk of MetS, among individuals with a low PAL.

Trends in dietary food groups and Dietary Approach to Stop Hypertension (DASH) score among adults: A longitudinal study from the Tehran Lipid and Glucose Study, 2006-2017.

OBJECTIVES: This study aimed to examine the secular trends of dietary food groups and diet quality among adults, overall and by sex, education, and employment status. METHODS: This study was conducted within the framework of the Tehran Lipid and Glucose Study. Demographic and anthropometric measurements were gathered using standard questionnaires. In terms of socioeconomic information, participants were divided into two groups according to their educational level and employment status. The regular dietary intakes of participants were gathered with a validated and reliable food frequency questionnaire over the previous year, and Dietary Approaches to Stop Hypertension scores were computed to evaluate diet quality. Generalized estimating equations were used to assess secular trends in food groups within the four phases. RESULTS: From 2006 to 2017, intake of whole grains, legumes, and nuts and seeds increased, and intake of refined grains, dairy products, and solid fats decreased significantly (P for trend < 0.001). Dietary fruit, vegetable, meat, and soft drink intake did not change significantly. According to socioeconomic groups, meat intake decreased significantly among men, uneducated, and unemployed participants, and fruit intake increased in both women and educated participants. Based on a 40-point scale, the Dietary Approaches to Stop Hypertension score increased from 18.1 ± 0.0 in phase1 to 22.7 ± 0.1 in phase 4 of the Tehran Lipid and Glucose Study (P for trend < 0.001). CONCLUSIONS: Over a decade, in addition to improvements in intake of a number of dietary food groups, the estimated overall diet quality of the study population showed a modest improvement. These findings may determine areas for more attention to improve the overall dietary intake of the population.

Socioeconomic and lifestyle factors modifies the association between nut consumption and metabolic syndrome incidence.

BACKGROUND & AIMS: The aim of this study was to evaluate the association of nut consumption and its various types with metabolic syndrome (MetS) risk and to investigate whether lifestyle factors (physical activity and smoking status) and socioeconomic status (education and occupation) modulate the association of nut consumption and the risk of MetS. METHODS: We prospectively studied 1915 participants of the Tehran Lipid and Glucose study, among whom 591 were diagnosed with MetS during 8.9 years of follow-up. Nut consumption and its various types were assessed using a validated semi-quantitative food frequency questionnaire. Multivariable adjusted Cox regression was used to estimate Hazard Ratios (HRs) for MetS events across tertiles of nut consumption and its various types. Regarding interaction between nut consumption and physical activity levels, education levels, and smoking status on the risk of MetS, using joint classification, the effect modification of lifestyle factors and socioeconomic status on the association between nut consumption (

TCF7L2 polymorphisms, nut consumption, and the risk of metabolic syndrome: a prospective population based study.

BACKGROUND: The aim of this study was to investigate whether two variants of the TCF7L2 (rs7903146 and rs12255372) modify the association between nut consumption and the risk of metabolic syndrome (MetS). Additionally, the modifying effect of weight change during follow-up on these associations was investigated. MATERIAL AND METHODS: We prospectively studied 1423 participants of the Tehran Lipid and Glucose study aged 19-74 years who were followed-up for dietary assessment using a validated, semi-quantitative food frequency questionnaire. Multivariable-adjusted Cox regression was used to estimate hazard ratios (HRs) for MetS events. Genotyping was performed by Human Omni Express-24-v1-0 chip. RESULTS: Over a median 8.9 years of follow-up, 415 new cases of MetS were documented. The median nut consumption was 20.0 g/week (Interquartile Range (IQR): 8.6-38.9 g/week). Regarding the rs7903146 genotype, in carriers of T allele (CT + TT), highest tertile of nut consumption was associated with a reduced risk of MetS after adjusting for confounders (HR: 0.67 (0.50-0.91)). Regarding the rs12255372 genotype, highest versus lowest tertile of nut consumption in participants with T allele (GT + TT) resulted in 34% reduction of MetS risk after adjustment for confounders (HR: 0.66 (0.49-0.69)). After stratification by weigh change (< 7% or ≥ 7% weight gain), in individuals with ≥ 7% weight gain, highest tertile of nut consumption was associated with reduced risk of MetS among the risk allele of rs7903146. In the risk allele of rs12255372, among individuals with < 7% weight gain, third tertile of nuts intake reduced the risk of MetS, after adjustment for confounders. CONCLUSION: Higher consumption of nuts may reduces the risk of MetS in T-risk allele of the TCF7L2 rs7903146 and rs12255372 variants and weight change may modify this association.

Does the association between patterns of fruit and vegetables and metabolic syndrome incidence vary according to lifestyle factors and socioeconomic status?

BACKGROUND AND AIMS: The aim of this study is to investigate the association between the identified patterns of fruits and vegetables and metabolic syndrome (MetS) incidence, and to investigate whether lifestyle factors and socioeconomic status modify the effect of the patterns on MetS risk. METHODS AND RESULTS: We prospectively studied 1915 participants of the Tehran Lipid and Glucose Study, who were aged 19-74 years and followed up for dietary assessment using a validated, semi-quantitative food frequency questionnaire. After adjustment for confounding factors, total vegetable intake was inversely related to the risk of MetS. Total fruit and total fruit and vegetable were not associated with MetS risk. We identified four major patterns of fruits and vegetables by factor analysis: "fresh fruit pattern", "vegetable pattern", "dried fruit and cruciferous vegetable pattern", and "potatoes and fruit juice pattern". "Vegetable pattern" was negatively associated with MetS risk, and "potatoes and fruit juice pattern" increased the risk of MetS. Among participants with weight gain <7% during follow-up, all four identified patterns reduced MetS risk. When stratified by smoking, "vegetable pattern" and "dried Fruit and cruciferous vegetable pattern" lowered MetS risk among non-smokers. Stratification based on education resulted in MetS risk reduction across tertiles of "fresh fruit pattern" and "vegetable pattern". First and second tertiles of "dried fruit and cruciferous vegetable pattern" lowered MetS risk among educated participants, compared to the reference. CONCLUSIONS: The reduction in MetS risk caused by fruits and vegetables intake depends on the modifying effect of lifestyle and socioeconomic factors.