Association of rs2282679 polymorphism in vitamin D binding protein gene (GC) with the risk of vitamin D deficiency in an iranian population: season-specific vitamin D status.

BACKGROUND: Genome-wide association studies in Western countries indicate a considerable impact of variations in vitamin D binding protein (GC) genes on serum concentrations of 25-hydroxyvitamin D (25(OH)D). We aimed to investigate an association between rs2282679 polymorphism in GC and vitamin D deficiency. METHODS: A cross-sectional study conducted in the framework of the Tehran Cardio-Metabolic Genetic Study (TCGS) cohort. A total of 1568 participants aged > 18 years were randomly selected, and their 25(OH) D concentration was measured. Vitamin D deficiency was assessed concerning rs2282679 by descriptive and multivariate analysis, odds ratio (OR), and 95% confidence intervals (95%CI) calculated. Since the interaction term between rs2282679 and recruitment season was significant, we performed regression analysis separately for individuals whose blood was taken in high sunny and those whose blood was drawn in the low sunny season. RESULTS: The rs2282679 polymorphism was in Hardy-Weinberg equilibrium (P > 0.05) in the studied population. The serum concentration of 25(OH) D median was 15.0 ng/mL, and the prevalence of VDD was 27.8%. The presence of the G allele in rs2282679 increases the risk of VDD in additive (OR = 1.35, 95% CI: 1.06-1.73) and dominant (OR = 1.33, 95% CI: 1.06-1.68) genetic models. After separating participants based on the recruitment season, the unfavorable association was observed in the additive and dominant only in the low sunny season. CONCLUSION: The finding of the current study indicates that the GC rs2282679 SNP is associated with vitamin D deficiency. It seems that the impact of risk allele increased in the low sunny season when UV exposure has been declined.

High dietary and lifestyle inflammatory scores are associated with increased risk of chronic kidney disease in Iranian adults.

BACKGROUND: Systemic inflammation can be the initiator in developing chronic diseases that may be affected by the lifestyle and diet of individuals. In the current study, we aimed to assess the association of the inflammatory potential of diet and lifestyle, determined by the food-based index of dietary inflammatory potential (FBDI), dietary inflammation score (DIS), and lifestyle inflammation score (LIS), with risk of chronic kidney disease(CKD) in Iranian adults. METHODS: A total of 6044 CKD-free individuals aged ≥ 18 years, were recruited from among participants of the Tehran Lipid and Glucose Study(surveys 3 and 4) and followed a mean of 6.03 years(follow-up rate:94.95%). Data on dietary intakes were determined using a food frequency questionnaire. The inflammatory potential of diet and lifestyle were determined based on three indices, including FBDI, DIS, and LIS. Using the National Kidney Foundation guidelines, we defined CKD as eGFR < 60 mL/min/1.73 m2. RESULTS: Mean ± SD age of the study population(54.3% women) was 37.8 ± 12.8 years. We identified 1216(20.1%) new cases of CKD during the 6.03 years of follow-up (46,889.8 person-years). In the multivariable-adjusted model, the risk of CKD incident is increased across quartiles of FBDI (HR = 1.21;95%CI:1.03-1.42, Ptrend:0.014) and LIS (HR = 1.28;95%CI:1.07-1.55,Ptrend:0.006). However, no significant relationship was observed between the higher DIS score and CKD risk. CONCLUSION: Our findings showed that a higher inflammatory potential of diet and lifestyle, characterized by a higher score of FBDI and LIS, was related to increased incidence of CKD, while no significant relationship was reported between the DIS score and CKD incident.

High insulinemic potential of diet and lifestyle is associated with increased risk of chronic kidney disease incident in adults.

BACKGROUND: The role of higher insulinemic effects of dietary pattern and lifestyle factors on the risk of chronic kidney disease (CKD) is not well-studied. In the current study, we aimed to investigate the relationship between the insulinemic potential of diet and lifestyle with the risk of CKD in adults. METHODS: A total of 6044 individuals without CKD, aged>18 years, were recruited from among participants of the Tehran Lipid and Glucose Study (third and fourth surveys) and followed a mean of 6.03 years(follow-up rate:94.95%). The dietary intake data were collected using a food frequency questionnaire. The insulinemic potential of diet and lifestyle was determined based on four empirical indices, including the empirical dietary index for hyperinsulinemia (EDIH), the empirical dietary index for insulin resistance (EDIR), the empirical lifestyle index for hyperinsulinemia (ELIH), and the empirical lifestyle index for insulin resistance (ELIR). RESULTS: Mean ± SD age of all study participants (54.3% women) was 37.8 ± 12.8 years. During the 6.03 years of follow-up (46,889.8 person-years), 1216(20.1%) new cases of CKD were identified. According to the multivariable-adjusted model, the risk of CKD incident is increased across quintiles of EDIR (OR = 1.29;95% CI: 1.06-1.57), ELIH (OR = 1.35; 95%CI: 1.10-1.67), and ELIR (OR = 1.24; 95%CI:1.02-1.51). However, no significant relationship was found between the EDIH score and the risk of CKD. CONCLUSION: Results of the current study showed that dietary pattern with a high EDIR score and a lifestyle with higher ELIH and ELIR scores may be related to increasing the risk of CKD incident. However, no significant association was observed between EDIH score and CKD incident.

Adherence to diet with higher dietary diabetes risk reduction score is associated with reduced risk of type 2 diabetes incident in Iranian adults.

BACKGROUND: The Dietary diabetes risk reduction score (DDRRS) has recently been considered by researchers as a diet quality index to predict the risk of chronic diseases, such as type 2 diabetes (T2D). In this study, we aimed to assess the association of DDRRS with T2D risk in Iranian adults. METHODS: Subjects aged ≥ 40 years without T2D (n = 2081) were selected for the current study from participants of the Tehran Lipid and Glucose Study (2009-2011) and followed for a mean of 6.01 years. We used the food frequency questionnaire to determine the DDRRS that is characterized by eight components, including higher consumption of nuts, cereal fiber, coffee, and polyunsaturated to saturated fat ratio and lower consumption of red or processed meats, trans fats, sugar-sweetened beverages, and high glycemic index foods. The multivariable logistic regression analysis was used to determine the odds ratio (ORs) and 95% confidence interval (CI) of T2D across the DDRRS tertiles. RESULTS: The mean ± SD age of individuals was 50.4 ± 8.2 years at baseline. The Median (25-75 interquartile range) DDRRS of the study population was 24(22-27). During the study follow-up, 233(11.2%) new cases of T2D were ascertained. In the age and sex-adjusted model, the odds of T2D were decreased across tertiles of DDRRS (OR = 0.68; 95%CI: 0.48-0.97, P for trend = 0.037). Based on the multivariable-adjusted model, after controlling all potential confounders, the risk of T2D is reduced across tertiles of DDRRS (OR = 0.66; 95%CI: 0.44-0.98, P for trend = 0.047). Also, higher scores (lower consumption) of red and processed meat (OR = 0.59; 95%CI: 0.39-0.88, P = 0.012) and sugar-sweetened beverages (OR = 0.49; 95%CI: 0.32-0.76, P = 0.002) as DDRRS components were associated with decreased T2D incident. CONCLUSIONS: Our findings suggested that a diet with a higher score of DDRRS may be related to reducing the risk of T2D in Iranian adults.

The relation of omentin gene expression and glucose homeostasis of visceral and subcutaneous adipose tissues in non-diabetic adults.

BACKGROUND: Adipose tissue (AT) is a passive reservoir for energy storage and an active endocrine organ responsible for synthesizing bioactive molecules called adipokines. Omentin is known as an anti-inflammatory adipokine that can modulate insulin sensitivity. The present study aimed to investigate the relationship between omentin mRNA expression and glucose homeostasis of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) in non-diabetic adults. METHODS: VAT and SAT adipose tissues were collected from 137 adults aged ≥ 18 years hospitalized for abdominal surgery. Before surgery, preoperative blood samples were taken from the participants to measure fasting plasma glucose, insulin, and triglyceride. BMI, HOMA-IR, HOMA-B, and QUICKI were calculated. Insulin levels were measured with Mercodia kits using enzyme-linked immunosorbent assay (ELISA). In order to obtain omentin mRNA expression, real-time PCR was performed. RESULTS: Overall, 91 (66.4%) subjects were healthy [without insulin resistance (IR)], and 46 (33.6%) participants were with IR. In healthy and IR subjects, omentin gene expression was 1.04 and 2.32, respectively in VAT, and 3.06 and 1.30, respectively, in SAT (P > 0.05). After controlling for age and BMI, linear regression analysis indicated a significant positive association of SAT omentin expression with insulin concentration (ß = 0.048; 95% CI 0.009, 0.088, P = 0.017) and HOMA-IR (ß = 0.173; 95% CI 0.023, 0.323, P = 0.014). Moreover, a negative association of SAT omentin expression with HOMA-B (ß = - 0.001; 95% CI 0.002, - 0.001, P < 0.001) was observed. CONCLUSION: This study's finding confirms a direct association between IR with omentin mRNA levels in SAT. Besides, the indicator of insulin sensitivity had an inverse association with omentin gene expression in SAT. This aspect of research suggests that omentin secretion from SAT has a strong link with insulin regulation.

The higher adherence to a healthy lifestyle score is associated with a decreased risk of type 2 diabetes in Iranian adults.

BACKGROUND: The combined roles of lifestyle factors in the risk of type 2 diabetes (T2D) are not fully investigated. In the present study, we aimed to assess the relationship between a healthy lifestyle score (HLS) and the risk of T2D in Tehranian adults. METHODS: A total of 3859 individuals without T2D were recruited from participants of the Tehran Lipid and Glucose Study (2009-2011) who were followed up for a mean period of 6 years. A food frequency questionnaire was used to collect individuals' dietary intakes at baseline. HLS scores was calculated based on three pre-defined methods with focusing on 4 lifestyle factors including, no current smoking, no obesity, high physical activity, and greater adherence to the healthy diet[determined using the alternate healthy eating index-2010(AHEI-2010), modified French Programme National Nutrition Santé-Guideline Score(mPNNS-GS), and healthy diet pattern score(HDP)]. RESULTS: Mean ± SD age of participants(44.4% men) was 41.1 ± 12.3 years. After 6-year follow-up of study, 295(7.6%) new cases of T2D were reported. Based on the age and sex-adjusted model, an inverse association was observed between the higher score of HLS-AHEI-2010 (OR = 0.24;95%CI:0.10-0.60), HLS-mPNNS-GS (OR = 0.28;95%CI:0.15-0.50), and HLS-HDP (OR = 0.39;95%CI:0.24-0.64) and the risk of T2D (P for trend < 0.05). Also, the fully-adjusted model showed that after controlling the effects of various confounders, this invers association between the higher score of HLS-AHEI-2010 (OR = 0.25;95%CI:0.10-0.61, P for trend:0.001), HLS-mPNNS-GS (OR = 0.29;95%CI:0.15-0.55,P for trend:0.001), and HLS-HDP (OR = 0.36;95%CI:0.22-0.61,P for trend < 0.001) and risk of T2D was remained significant. CONCLUSION: The results of this study suggested that higher score of HLS, characterized by no smoking, normal body weight, vigorous physical activity, and healthy diet, is related to decreased risk of T2D incidence.

High Dietary Diabetes Risk Reduction Score Is Associated with Decreased Risk of Chronic Kidney Disease in Tehranian Adults.

Aim: In the current study, we examined the association of dietary diabetes risk reduction score (DDRRS) with chronic kidney disease (CKD) among an Iranian adult population. Methods: We followed up 2076 ≥20-year-old participants of the Tehran Lipid and Glucose Study (2006-2008), who were initially free of CKD for 5.98 years. The dietary diabetes risk reduction score was calculated based on scoring eight components, including cereal fiber, nuts, coffee, polyunsaturated fatty acids-to-saturated fatty acids ratio, glycemic index, sugar-sweetened beverages, trans fatty acids, and red and processed meat using a valid and reliable 168-item food frequency questionnaire. CKD was defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2. A Cox proportional hazard regression model was used to assess the association between the quartiles of DDRRS and CKD incidence. Results: Mean ± SD age of the study population (53% women) was 37.6 ± 12.61 years. During 5.98 years of follow-up, 357 incident cases of CKD were reported. The median (25-75 interquartile range) of DDRRS was 20 (18-22). After adjustment for age, sex, smoking status, total energy intake, body mass index, hypertension, diabetes, eGFR, and physical activity, individuals in the highest versus lowest quartile of DDRRS were 33% less likely to have CKD (HR: 0.67; 95% CI: 0.48-0.96, P for trend: 0.043). Conclusion: The present study's findings suggest that greater adherence to a dietary pattern with a higher score of DDRRS may be associated with a lower risk of CKD incident.

Changes in ideal cardiovascular health among Iranian adolescents: 2007-2008 to 2015-2017.

BACKGROUND: Assessment of both behavior and factors of health as ideal cardiovascular health (iCVH) in adolescence could contribute to cardiovascular disease prevention in adulthood. AIMS: To explore the changes in the prevalence of iCVH and its components during a decade among Tehranian adolescents. METHODS: The 12-19 years old adolescents were selected from the Tehran Lipid and Glucose Study(TLGS). The iCVH score was calculated in the study period 1 (2007-2008; n = 267) and 2 (2015-2017; n = 336). To calculate iCVH, body mass index(BMI), systolic and diastolic blood pressure (BP), total cholesterol, fasting plasma glucose (FPG), physical activity, smoking status, and dietary intakes were measured by standard protocols. The changes in iCVH components between the two study periods were reported by prevalence (95% confidence interval). A logistic regression model was conducted to test the effects of study periods, sex, and age groups on the iCVH(≥ 6 scores). RESULTS: Overall, there was a reduction in the prevalence of ideal FPG (97.4 vs. 91.1%) and ideal BP(91.8 vs. 82.7%). Girls had a decrease in the prevalence of ideal BP(91.2 vs. 79.4%) as well as an increase in non-smoking status(77.6 vs. 89.7%). However, the prevalence of ideal FPG (96.5 vs. 88.5%) and ideal BP(92.2 vs 85.0%) decreased in boys. Study period 2, compared to period 1 was associated with lower odds of having iCVH. Furthermore, boys were 1.57 folds more likely to have ideal CVH factors than girls. CONCLUSION: There was a decrease in the prevalence of ideal CVD metrics, including FPG and BP, after one decade. Generally, adolescent boys had higher odds of having ideal CVH compared to girls.

Dietary Amino Acid Patterns Are Associated With Incidence of Chronic Kidney Disease.

OBJECTIVES: No findings are available regarding the association of the dietary amino acid (AA) intakes with the risk of chronic kidney disease (CKD) in adults. We aimed to assess the association between dietary AA patterns and incidence of CKD in adults. DESIGN AND METHODS: This study was conducted within the framework of Tehran Lipid and Glucose Study on 4,233 adults, who were free of CKD at baseline (2009-2011) and were followed for 3.1 years (2011-2014). The principal component analysis was used based on 8 AA groups to characterize major AA patterns. Multivariable logistic regression models were used to estimate the risk of CKD across quartiles of dietary AA pattern scores. RESULTS: Three major AA patterns were extracted: (1) higher loads of branched-chain, alcoholic, and aromatic AAs; (2) higher loads of acidic AAs, proline, and lower load of alkaline AAs and small AAs; and (3) higher loads of sulfuric AAs and small AAs. The mean ± standard deviation age of participants (45.9% male) was 39.4 ± 11.7 at baseline and the incidence of CKD was 12.1% (513 cases) after 3.1 years of follow-up. The highest score of first dietary AA pattern tended to be associated with an increased risk of CKD (odds ratio = 1.43, 95% confidence interval1.06-1.93); however, the second pattern was related to a decreased risk of CKD (odds ratio = 0.71, 95% confidence interval: 0.52-0.97) in the multivariable model. CONCLUSION: These novel findings suggest that the dietary AA patterns may modify risk of CKD.

Association of Dietary Diabetes Risk Reduction Score With Risk of Cardiovascular Diseases in the Iranian Population: Tehran Lipid and Glucose Study.

BACKGROUND: There are no data available regarding the association of dietary diabetes risk reduction score (DDRRS) and risk of cardiovascular disease (CVD) worldwide. We aimed to investigate the association of the DDRRS with the risk of CVD outcomes in a prospective population-based study. METHOD: Individuals without CVD (n=2,195) were recruited from participants of the Tehran Lipid and Glucose Study (2006-2008) and followed for a mean of 6.7 years. The DDRRS was determined on the basis of eight components using a validated 168-item food frequency questionnaire. Cox proportional hazard regression models, adjusted for potential confounders, were used to estimate the hazard ratios and 95% confidence interval (CI) of CVD across quartiles of DDRRS. RESULTS: The mean ± standard deviation age of participants (44.8% male) was 38.8±13.0 years at baseline. Median DDRRS for all patients was 23 (intequartile range 20-26). During follow-up, 77 (3.5%) new cases of CVD were identified. After adjustment for confounding variables, including age, sex, body mass index, physical activity, smoking, energy intake, diabetes, and hypertension, no association was found between DDRRS and risk of CVD (odds ratio, 0.70; 95% CI, 0.36-1.37 [p-value for trend=0.351]). CONCLUSIONS: The findings of this study showed that higher DDRRS is not associated with risk of CVD events.

Does trans fatty acid affect low birth weight? A randomised controlled trial.

To evaluate the effect of low trans fatty acids (TFAs) dietary patterns during pregnancy on the risk of low birth weight (LBW). All pregnant women who received prenatal care with gestational age <8 weeks in this study took place in Tehran from December 2014 to August 2016. Women in the intervention group received dietary patterns with TFAs content of < 1%; those in the control group had dietary intake without any change in TFAs content. Dietary intakes were assessed by 3 non-consecutive 24-hour recalls in three trimesters. Hazard ratio (HR) was calculated using Cox proportional-hazards models. Incidence and HR (95% CI) for LBW based on multivariable adjusted models were calculated. Of the 800 women (n = 407 in control and n = 393 in intervention groups), 108 (13.5%) women were diagnosed with LBW. The incidence of LBW in the intervention group was 12% and in the control group was 19%. After multivariable adjustment for confounders, the HR for incident LBW in the intervention group was 0.65 (0.44-0.96). Kaplan-Meier plot showed a significant difference between the two groups in the incidence of LBW. Intake of low TFAs dietary patterns during pregnancy reduced the risk of LBW. IMPACT STATEMENTWhat is already known on this subject? Maternal nutrition affects foetal development, and one important dietary determinant of foetal growth may be trans fatty acids (TFAs). It is generally advised to avoid high-fat dairy products that are the main sources of TFAs during pregnancy; however, there is limited data on the effects of a diet of LBW.What do the results of this study add? Intake of low TFAs dietary patterns during pregnancy reduced the risk of LBW. In this study, the risk of LBW in the intervention group decreased by about 50%.What are the implications of these findings for clinical practice and/or further research? The results of this study could give physicians and other health care providers the hint that Management of maternal nutrition with focussed on TFAs content should be included in routine prenatal care, to facilitate interventions and guidance regarding maternal nutrition.

Elevated miR-143 and miR-34a gene expression in human visceral adipose tissue are associated with insulin resistance in non-diabetic adults: a cross-sectional study.

OBJECTIVE: We aimed to evaluate the association of miR-143 and miR-34a expression in human visceral (VAT) and subcutaneous (SAT) adipose tissues with insulin resistance (IR). METHODS: VAT and SAT were obtained from 176 participants without diabetes. miR-143 and miR-34a expressions in VAT and SAT were measured using qRT-PCR. Fasting serum insulin and glucose concentration, homeostatic model assessment of IR index (HOMA-IR) and ß-cell function (HOMA-B), and quantitative insulin-sensitivity check index (QUICKI) were calculated. RESULTS: After adjustment for age, sex and body mass index (BMI), VAT miR-143 expression was positively associated with fasting plasma glucose (FPG), insulin, and HOMA-IR, and negatively associated with HOMA-B and QUICKI. miR-34a expression in VAT was directly associated with FPG, insulin, and HOMA-IR and negatively associated with QUICKI. In SAT, miR-34a expression was positively associated with insulin and negatively associated with QUICKI. The interaction terms of HOMA-IR and BMI categories were significant for both miR gene expressions in VAT. After stratifying participants based on BMI, the association of miR-143 and miR-34a expressions in VAT with IR indices remained significant only in obese patients. CONCLUSION: miR-143 and miR-34a expressions in VAT were independent predictors of IR in people without diabetes, and that this association was conditional on the degree of obesity. LEVEL OF EVIDENCE: Level of evidence III, cross-sectional analytic study.

Daily vitamin D3 in overweight and obese children and adolescents: a randomized controlled trial.

PURPOSE: To assess the efficacy of different doses of vitamin D3 on serum 25-hydroxyvitamin D (25(OH)D), intact parathyroid hormone(iPTH), calcium, phosphorus, and alkaline phosphatase concentrations in overweight and obese school-children. METHODS: A total of 378 children and adolescents, 6-13 years of age, with age- and sex-specific body mass index(BMI) Z-score ≥ 1(according to the World Health Organization criteria) were allocated to receive 600, 1000, and 2000 IU vitamin D3/days. 25(OH)D, iPTH, calcium, phosphorus, and alkaline phosphatase concentrations were measured at baseline, 6, and 12 months. In this intention-to-treat analysis, we fitted a linear mixed effect model involving a random effect of participants within treatment groups and fixed effects of dose, time, and their interactions. RESULTS: Mean(SD) of age and BMI Z-score were 9.3 (1.7) years and 2.55 (0.73), respectively. The median (IQR) for 25(OH)D was 11.5 (8.9), 11.7 (10.5), 12.2 (10.2) ng/mL (28.75, 29.25, and 30.50 nmol/L) at baseline and 23.1 (8.0), 25.6 (8.3), 28.6 (10.4) ng/mL (57.75, 64.00, and 71.50 nmol/L) at the end of 12 months in 600, 1000, and 2000 IU, respectively (p values for dose, time, and the interaction being < 0.0001, < 0.0001,and 0.082, respectively). Prevalence of vitamin D deficiency (< 20 ng/mL) was 80.2, 77.5, and 75.5% in 600, 1000, and 2000 IU groups at baseline, respectively, which decreased to 34, 18.4, and 7.5%, respectively, at 12 months. Patterns of iPTH, calcium, phosphorus, and alkaline phosphatase response over time did not differ significantly among groups (p values = 0.452, 0.670, 0.377, 0.895, respectively). CONCLUSIONS: Increases in 25(OH)D concentration were found with supplementation of 1000 and 2000 IU, compared with 600 IU/days, whereas there was no evidence of iPTH suppression or change in serum calcium, phosphorus, and alkaline phosphatase among children with excess weight.

The association of dietary and plasma fatty acid composition with FTO gene expression in human visceral and subcutaneous adipose tissues.

PURPOSE: The human obesity susceptibility gene, FTO, associates with body mass and obesity in humans through regulation of energy expenditure and intake. We aimed to determine how fatty acids in plasma and in diet associate with FTO gene expression in subcutaneous and visceral adipose tissues. METHODS: In this study, 97 participants aged ≥ 18 years were selected from patients admitted to the hospital for abdominal surgeries. Habitual dietary intake of participants was collected using a valid and reliable food frequency questionnaire (FFQ), from which the intake of fatty acids was quantified. Plasma fatty acids were assessed by gas-liquid chromatography. The mRNA expression of the FTO gene in visceral and subcutaneous adipose tissues obtained by biopsy was measured by Real-Time Quantitative Reverse Transcription PCR. Standardized ß-coefficients were calculated by multivariable linear regression. RESULTS: After adjusting for age, homeostasis model insulin resistance index (HOMA-IR), and body mass index, total fatty acid intake was significantly associated with FTO gene expression in visceral (STZß = 0.208, P = 0.037) and subcutaneous (STZß = 0.236, P = 0.020) adipose tissues. Dietary intake of monounsaturated fatty acid (MUFA) and polyunsaturated fatty acids (PUFA) had positive significant associations with the expression of FTO in visceral (STZß = 0.227, P = 0.023; STZß = 0.346, P < 0.001, respectively) and subcutaneous (STZß = 0.227, P = 0.026; STZß = 0.274, P = 0.006, respectively) adipose tissues. There were no associations between plasma fatty acids and FTO mRNA expression in either subcutaneous or visceral adipose tissues. CONCLUSION: The weak association of dietary total fatty acids, MUFA, and PUFA with FTO gene expression in both adipose tissues may highlight the importance of dietary fatty acids composition along with total fat intake in relation to FTO gene expression.

The association of dietary diabetes risk reduction score and its components with risk of metabolic syndrome incident in Tehranian adults.

BACKGROUND: Evidence of possible beneficial effects of dietary diabetes risk reduction score (DDRRS) on reducing the risk of various chronic diseases such as metabolic syndrome (MetS) are limited. This is a prospective, population-based cohort study, which aimed to investigate the relationship of the DDRRS and its components with MetS incident in Iranian adults. METHODS: Individuals without MetS (n=3561) were recruited from participants of the Tehran Lipid and Glucose Study (2009-2011) and followed for a mean of 6.01 years. A validated food frequency questionnaire was used to determine the DDRRS using based on eight components, including higher intakes of cereal fiber, nuts, coffee, and polyunsaturated: saturated fat ratio and lower intakes of red or processed meats, sugar-sweetened beverages, trans fatty acids, and low glycemic index. We used the multivariable logistic regression analysis to determine the odds ratio (ORs) and 95 % confidence interval (CI) of MetS across the tertiles of DDRRS. RESULTS: The mean (SD) age of individuals was 38.1(12.6) years at baseline. Median (25-75 interquartile range) DDRRS for all participants was 20(18-22). During the study follow-up, 682(19.1 %) new cases of MetS were reported. Based on the age and sex-adjusted model, participants in highest tertile of DDRRS had lower risk of MetS in compared with the lowest one (OR=0.64;95 %CI:0.52-0.79, P for trend=0.001). In the multivariable adjusted model, after adjustment for all possible confounding variables, the risk of MetS is decreased across tertiles of DDRRS (OR=0.60;95 %CI:0.48-0.75, P for trend=0.001). Also, higher scores of some DDRRS components including red and processed meat, sugar sweetened beverages, and coffee were related to decreased incidence of MetS. CONCLUSIONS: The results of this study revealed that greater adherence to DDRRS can be associated with decreased risk of MetS in Iranian adult.

Association of plasma fatty acids pattern with omentin gene expression in human adipose tissues: A cross-sectional study.

BACKGROUND AND AIMS: Omentin, as an adipokine, has been reported to improve insulin resistance and inflammation may be related to fatty acids (FAs). Plasma FAs can be used as biomarkers of dietary FAs and endogenous FA exposure. We aimed to evaluate the association between plasma FAs pattern and omentin gene expression in adipose tissue (AT). METHODS AND RESULTS: Visceral and subcutaneous AT and fasting blood were gathered from 97 adults aged >18 years. Participants were already admitted to hospitals for elective abdominal surgery. Dietary intakes were assessed using a food frequency questionnaire. The relative omentin gene expression in visceral and subcutaneous AT was measured by Real-Time PCR and plasma FAs was determined by gas chromatography. The principal component analysis was performed to derive the FAs pattern from plasma individual FAs. Three patterns were derived from plasma FAs, 1) high de-novo lipogenesis (DNL), 2) high trans saturated fatty acids (SFA), and docosahexaenoic acid (trans-SFA/DHA), and 3) high long-chain SFA (LC-SFA). After adjustment for age, sex, and insulin concentration, only the LC-SFA pattern was associated with omentin gene expression in visceral AT (ß = 2.25, P = 0.03). Other patterns were not associated with omentin gene expression in visceral and subcutaneous AT. CONCLUSION: A pattern characterized by high levels of myristic acid (14:0), heptadecanoic acid (17:0), pentadecanoic acid (15:0), and Cis_heptadecanoic acid (17:1), which named LC-SFA was related to omentin gene expression in visceral AT.

Changes in dairy product consumption and subsequent type 2 diabetes among individuals with prediabetes: Tehran Lipid and Glucose Study.

BACKGROUND: People with prediabetes can postpone or even reverse progression to type 2 diabetes (T2D) by making dietary changes. This study aimed to examine the association of changes in consumption of total and specific types of dairy products with the subsequent risk of incident T2D among individuals with prediabetes. METHOD: This cohort study included 639 individuals (50% female, mean age 47.3 years) of the Tehran Lipid and Glucose Study (TLGS) who had prediabetes at baseline. We assessed 3-year changes in the consumption of dairy products using a food frequency questionnaire. Using multivariable logistic regression, odds ratios (OR) and 95% confidence intervals (CI) were calculated for the association of changes in intake of total and subtypes of dairy products during a 3-year interval with the risk of incident T2D in the subsequent 3 years. RESULTS: After almost 9 years of follow-up, the incidence of T2D was 25.2%. Compared with individuals whose intake remained relatively stable over 3 years, those who decreased consumption of total dairy (> 0.5 servings/day) had a higher T2D risk (OR = 1.56; 95% CI: 1.02 to 2.41). Increasing low-fat dairy consumption by 0.50 serving/d was associated with a lower risk of T2D (OR = 0.56; 95% CI: 0.35 to 0.90) compared with stable consumption. Those who increased consumption of low-fat milk (OR = 0.59; 95% CI: 0.37 to 0.92) and low-fat yogurt (OR = 0.55; 95% CI: 0.33 to 0.93) had a lower risk of T2D than those who were relatively stable in their consumption. Replacing low-fat milk and yogurt with regular cheese was associated with 66 and 47% higher risk of T2D, respectively. CONCLUSION: In individuals with prediabetes, increasing consumption of low-fat dairy, low-fat milk, and low-fat yogurt had reduced risk of subsequent T2D. These data suggest a role of low-fat dairy products in the prevention of T2D among prediabetes patients.

Dietary intakes of total polyphenol and its subclasses in association with the incidence of chronic kidney diseases: a prospective population-based cohort study.

BACKGROUND: As chronic kidney disease (CKD) is amongst the current global health challenges, this study is aiming to evaluate the long-term intake of total polyphenol and its subclasses in association with CKD incidence. METHODS: For the purpose of this study, a sample of 3021 Iranian adults (47 % men, aged 20-79 years) with no CKD diagnosis at baseline, were selected from the Tehran Lipid and Glucose Study population. The total intake of polyphenol and its major subclasses were assessed by a validated food frequency questionnaire and categorized as flavonoids, phenolic acids, stilbenes, and lignans. Although the morphological abnormalities of the kidneys or 3-month persistent urinalysis can distinctively define CKD, the glomerular filtration rate (eGFR) reduction is accepted as a more precise index of renal function. Therefore, eGFR < 60 mL/min/1.73m2 was the exclusive index of CKD diagnosis in the current study. The eGFR was calculated by the Modification of Diet in Renal Disease Study equation. Cox-regression analysis was used to assess the hazard ratio and 95 % confidence intervals of CKD in quartiles of the total polyphenols. RESULTS: In this study, 355 CKD cases over 11,058.464 person-years was reported. The median (IQR) age of participants was 36 years (27-46) at baseline. Moderate intake of lignans (≤ 6.8 mg) was negatively associated with the incidence of CKD in the adjusted model. No significant associations were detected between higher amounts of lignin and total polyphenols (HR: 0.97, 95 % CI 0.67-1.40) and CKD incidence. CONCLUSIONS: Based on the current findings, moderate intake of lignin possess CKD-protective properties by approximately 32 %. No independent associations were observed between higher amounts of lignins and CKD incidence.

Longitudinal association of dietary sources of animal and plant protein throughout childhood with menarche.

BACKGROUND: Inconsistent findings have been reported for associations between protein intake and age at menarche. We aimed to investigate the association between intake of protein and protein-containing food groups during childhood with menarche among Iranian girls. METHODS: Girls aged 6-18 years who did not experience menarche in the third or fourth examination cycles of the Tehran Lipid and Glucose Study were selected and were followed to the fifth examination cycle. Daily intakes of protein from different animal/plant sources and ten protein-containing food groups were assessed using a food frequency questionnaire at baseline (the third or fourth examination cycles). Occurrence of menarche and its onset age were asked during each examination cycle. Cox proportional hazards regression was used to estimating hazard ratios (HRs) and 95% confidence interval (95%CI) for the occurrence of menarche per one standard deviation (SD) of dietary intakes. Logistic regression was also used to estimate the odds of reaching menarche ≤12 years. RESULTS: During the study, 147(61%) of girls reached menarche, the median age at menarche was 12 years. The adjusted HRs (95% CI) for the occurrence of menarche per one-SD of dietary intakes were 0.68 (0.48, 0.98; p = 0.040) for plant protein and 1.36 (1.01, 1.84; p = 0.042) for animal protein after adjusting for baseline age, BMI Z-score, energy intake, and mother's early menarche and education. Substituting 10-g animal protein with plant protein was associated with a 16% (95%CI: 5-25%; p = 0.006) lower risk of menarche. Dietary intakes of poultry (adjusted HR: 1.35; 95% CIs: 1.00-1.82; p = 0.049) and low-fat dairy (adjusted HR: 1.20; 95%CIs: 0.99-1.46; p = 0.064) were marginally associated with the increased risk of menarche. However, the odds of early menarche was significant only for plant protein (adjusted odds ratio = 0.39; 95% CI: 0.16-0.96; p = 0.040). CONCLUSIONS: Our findings indicate that the risk of menarche increases by higher intakes of animal protein and decreases by plant protein. Intakes of poultry and low-fat dairy associate with a higher risk of menarche. The odds of menarche occurrence ≤12 years reduces by higher intakes of plant protein.

Low-carbohydrate diet and cardiovascular diseases in Iranian population: Tehran Lipid and Glucose Study.

BACKGROUND AND AIMS: Studies indicated that the risk of cardiovascular disease (CVD) in association to greater adherence to low-carbohydrate diet (LCD) differs in various populations. In this study, we aimed to assess the association of LCD score with the risk of CVD events in a prospective population-based study. METHODS AND RESULTS: CVD-free participants (n = 2188) were recruited from the Tehran Lipid and Glucose Study (2006-2008) and followed for a mean of 6.7 years. Using a valid and reliable 168 item semi-quantitative food frequency questionnaire, the LCD score was determined based on the percentage of energy as carbohydrate, protein, and fat, which ranged from 0 to 12. Cox proportional hazard regression models, adjusted for potential confounders, were used to estimate the hazard ratios (HRs) and 95% confidence interval (CI) of CVD across tertiles of LCD score in women and men. Mean ± SD age of participants (44.8% male) was 38.8 ± 13.0 years, and median (25-75, interquartile range) of the LCD score was 6 (4-8) at baseline. During follow-up, 77 (3.5%) new cases of CVD were identified. After adjustment for sex, age, body mass index, physical activity, smoking, energy intake, diabetes, and hypertension, there was no association between the LCD score and risk of CVD outcomes in all participants (HR = 0.93; 95% CI: 0.86-1.02) and women (HR = 1.13; 95% CI: 0.94-1.36); however, the LCD score was associated with an 11% reduced incidence of CVD events in men (HR = 0.89; 95% CI: 0.80-0.98), (P for trend: 0.028). CONCLUSION: Findings showed that higher adherence to LCD may be associated with a lower risk of CVD outcomes in men but not in women.