The association of insulinemic potential of diet and lifestyle with the risk of insulin-related disorders: a prospective cohort study among participants of Tehran Lipid and Glucose Study

Background: We aim to assess the association of empirical dietary (EDIH) and lifestyle (ELIH) index for hyperinsulinemia with the risk of insulin resistance, hyperinsulinemia, insulin sensitivity, and β-cell dysfunction in Iranian adults. Methods: In this prospective study, a total of 1244 men and women aged � 20 years were selected among participants of the Tehran lipid and glucose study and followed for 3.2 years. Dietary intakes were assessed using a valid semi-quantitative food frequency questionnaire. Dietary and lifestyle insulinemic potential indices were calculated using dietary intake, body mass index, and physical activity information. Multivariable logistic regression was used to estimate the associated risk of a 3-year incidence of insulin-related disorders. Results: The mean ± SD age and BMI of all eligible participants (42.7 males) were 43.0 ± 13.0 and 27.4 ± 4.9 in the study's baseline. After adjusting for all potential confounders, participants in the highest tertile of ELIH score had a greater risk of developing hyperinsulinemia (OR:2.42, 95CI:1.52�3.86, P for trend = < 0.001), insulin resistance (OR:2.71, 95CI:1.75�4.18, P for trend = < 0.001) and insulin insensitivity (OR:2.65, 95CI: 1.72�4.10, P for trend = < 0.001) compared with those in the lowest tertile. However, the risk of incident β-cell dysfunction was lower in individuals with a higher score of ELIH in comparison to those with the lowest score (OR:0.30, 95CI:0.19�0.45, P for trend = < 0.001). Conclusions: Empirical lifestyle index for hyperinsulinemia was directly associated with insulin resistance, insulin insensitivity, and hyperinsulinemia and was inversely associated with β-cells dysfunction. © 2021, The Author(s)

The association between dietary glycemic and insulin indices with incidence of cardiovascular disease: Tehran lipid and glucose study

Background: The present study was conducted to investigate the association of dietary insulin index(II), insulin load(IL), glycemic index(GI), and glycemic load(GL) with the risk of cardiovascular disease(CVD). Methods: This cohort study was conducted within the framework of the Tehran Lipid and Glucose Study on 2198 subjects, aged�19 years old, who were followed-up for a median (IQR) 6.7 (6.1-7.1) years. Dietary GI, GL, II, and IL were calculated using a food frequency questionnaire at the baseline. Multivariate Cox proportional hazard regression models were used to estimate the risk of CVD across quartiles of dietary insulin and glycemic indices. Results: Mean ± SD age of the subjects(44.9 men) was 38.3 ± 13.4 years. During a mean of 2406 ± 417 person-years of follow-up, 76(3.5) new cases of the CVD were ascertained. The mean ± SD of II, IL, GI, and GL of participants were 51.7 ± 6.5, 235.8 ± 90.2, 61.9 ± 7.8, and 202.2 ± 78.1, respectively. After adjusting for the variables of age, sex, smoking, physical activity, daily energy intake, body mass index, diabetes, and hypertension, the hazard ratio (HR) of the highest quartile of dietary GL was 2.77(95CI:1.00-7.69,P for trend:0.033) compared to the lowest one. Also, each one SD increase in the GL score was associated with a higher risk of CVD(RR:1.46;CI:1.00-2.16),P-value = 0.047. However, there was no significant association between the dietary GI, II, and IL and risk for CVD incidence. Conclusions: Our results suggested that a high GL diet can increase the incidence of CVD, whereas high dietary II and IL were not associated with the risk of CVD among adults. © 2020 The Author(s)

Animal based low carbohydrate diet is associated with increased risk of type 2 diabetes in Tehranian adults

Background: To investigate the association of low carbohydrate diet (LCD) score with the risk of type 2 diabetes among adults. Methods: This cohort study was conducted on 4356 healthy participants aged � 19 years old, who were followed-up for a mean duration of 3 years within the framework of the Tehran Lipid and Glucose Study. LCD score was calculated using a food frequency questionnaire according to intake of carbohydrate, protein, and fat at baseline. Diabetes was defined according to the criteria of the American Diabetes Association. Multivariable logistic regression models, adjusted for potential confounders, were used to estimate risk of diabetes across quartiles of LCD score. Results: Mean ± SD age of the study participants (44.4 men) was 40.5 ± 13.0 years. The median (25-75 interquartile range) of LCD score was 17.0 (12.0-21.0) and after a 3 year follow-up period, 123 (2.8) incident cases of diabetes were ascertained. After adjustment for confounding variables, including age, sex, smoking status, physical activity, total calorie intake, saturated fatty acid, waist circumference, educational level, and family history of diabetes, the multivariable-adjusted ORs (95 CIs) of type 2 diabetes, comparing the highest with the lowest quartiles, were 2.16 (1.16-4.04) for total LCD score (P-value = 0.015), 1.81 (1.06-3.11) for animal-based LCD score (P-value = 0.029), and 1.47 (0.85-2.52) for plant-based LCD score (P-value = 0.160). Conclusion: Our findings suggest that a higher adherence to LCD, mostly with higher intakes of protein and fat from animal-source foods, can increase the incidence of diabetes; however, a plant-based low-carbohydrate dietary pattern is not significantly associated with risk of type 2 diabetes. © 2020 The Author(s)

Association of the insulinemic potential of diet and lifestyle with risk of diabetes incident in Tehranian adults: a population based cohort study

Background: We aimed to assess the associations between insulinemic potential of diet and lifestyle and the risk of diabetes incident, using four empirical indices including the empirical dietary index for hyperinsulinemia (EDIH), the empirical dietary index for insulin resistance (EDIR), empirical lifestyle index for hyperinsulinemia (ELIH), and empirical lifestyle index for insulin resistance (ELIR). Methods: A total of 3734 individuals, aged � 20 years old, who were free of diabetes at baseline (2008�2011), were followed for 6.2 years (2015�2018) to ascertain incident diabetes. The food frequency questionnaire was used to collect dietary intakes at baseline. Odds ratio (OR) of diabetes were calculated across quartiles of EDIH, EDIR, ELIH, and ELIR using logistic regression, which controlled for confounding factors. Results: The mean ± SD age and BMI of individuals (45.1 male) were 40.9 ± 12.0 years and 27.1 ± 4.1 kg/m2, respectively. At the end of follow-up, 253 (6.8 ) diabetes cases were identified. In the multivariable-adjusted model, individuals in the highest quartile of EDIR (1.58;95 CI:1.03�2.44, P for trend = 0.025), ELIH (1.89;95 CI:1.20�2.97, P for trend = 0.004), and ELIR (1.74; 95 CI:1.11�2.72, P for trend = 0.031) had increased the risk of diabetes. However, no significant associations were found between the score of EDIH and diabetes incident. Conclusions: Higher adherence to EDIR, ELIH, and ELIR scores were associated with increased risk of diabetes, while no significant association was found between EDIH score and diabetes incident. © 2021, The Author(s)

Dietary and lifestyle inflammatory scores and risk of incident diabetes: a prospective cohort among participants of Tehran lipid and glucose study

Background: Inflammation is a precursor of chronic disease, which is affected by lifestyle and dietary habits. Recently empirical dietary inflammatory patterns (EDIP), dietary inflammation scores (DIS), and lifestyle inflammation scores (LIS) were developed to indicate lifestyle and dietary contributions in systemic inflammation. The current study aimed to investigate the associations between these indices and the incidence of diabetes among Tehranian adults. Methods: A total of 4624 individuals, aged 20�75 years, who were free of diabetes at baseline (2008�2011), were followed for 5.71 years (2014�2017) to ascertain incident diabetes. Dietary intakes were collected at baseline using the food frequency questionnaire. The hazard ratio (HR) of diabetes was calculated by Cox proportional hazards regression across quartiles of EDIP, DIS, and LIS, adjusted for potential confounders. Results: The mean ± SD for the age and BMI of the study population (45.1 male) were 40.8 ± 12.7 years and 27.1 ± 4.1 Kg.m2, respectively. At the end of the follow-up, 329 (7.1) diabetes cases were identified. In the multivariable-adjusted model, individuals in the highest compared to the lowest quartile of EDIP (HR = 0.83; 95CI:0.59�1.15, p for trend = 0.286), and LIS (HR = 2.41; 95CI:1.61�3.60, P for trend < 0.001) had increased risk of diabetes. However, no significant associations were found between the score of DIS and diabetes incidents (HR = 0.83; 95CI:0.59�1.15, p for trend = 0.286). Conclusion: Greater adherence to EDIP and LIS scores was associated with a higher risk of diabetes, while no significant association was found between the DIS score and diabetes incident. © 2021, The Author(s)

Spinach consumption and nonalcoholic fatty liver disease among adults: a case�control study

Background: Spinach has high antioxidants and polyphenols and showed protective effects against liver diseases in experimental studies. We aimed to assess the association between dietary intake of spinach and odds of nonalcoholic fatty liver disease (NAFLD) in a case�control study among Iranian adults. Methods: Totally 225 newly diagnosed NAFLD patients and 450 controls, aged 20�60 years, were recruited in this study. Participants� dietary intakes were collected using a valid and reliable 168-item semi-quantitative food frequency questionnaire (FFQ). The logistic regression test was used for assessing the association between total, raw, and boiled dietary spinach with the odds of NAFLD. Results: The mean (SD) age and BMI of participants (53 male) were 38.1 (8.8) years and 26.8 (4.3) kg/m2, respectively. In the final adjusted model for potential confounders, the odds (95 CI) of NAFLD in individuals in the highest tertile of daily total and raw spinach intake was 0.36 (0.19�0.71), P_trend = 0.001 and 0.47 (0.24�0.89), P_trend = 0.008, respectively compared with those in the lowest tertile. Furthermore, in the adjusted analyses, an inverse association was observed between the highest yearly intake versus no raw spinach consumption and odds of NAFLD (OR 0.41; 95% CI 0.18�0.96), P for trend = 0.013. However, there was no significant association between higher boiled spinach intake and odds of NAFLD. Conclusions: The present study found an inverse association between total and raw spinach intake with the odds of NAFLD. © 2021, The Author(s)

Antioxidant vitamin intakes and risk of depression, anxiety and stress among female adolescents

Background and aim: The relation of some antioxidant nutrients with psychological disorders has been studied previously. The aim of this study was to examine the association between antioxidant vitamin intakes and the risk of depression, anxiety, and stress. Methods: This cross-sectional study was conducted on 263 Tehranian female adolescents. Dietary intakes of vitamin E, C, and β-Carotene were determined using a valid and reliable food-frequency questionnaire. Depression, anxiety, and stress scores were characterized by DASS-21 (Depression Anxiety Stress Score-21 items) questionnaire. The multivariable logistic regression models were used to determine the odds ratios (ORs) and 95 confidence intervals (95CIs) of depression, anxiety, and stress across tertiles of antioxidant vitamin intakes. Results: The mean ± SD age of participants was 16.20 ± 0.97 years. Also, the mean ± SD depression, anxiety and stress scores of participants were 9.89 ± 4.15, 8.43 ± 4.39 and 14.00 ± 6.45, respectively. In the fully adjusted model, subjects in the highest tertile of β-Carotene had a lower prevalence of depression (OR:0.46, 95CI:0.23�0.95), anxiety (OR:0.40, 95CI:0.20�0.81), and stress (OR:0.35, 95CI:0.17�0.73) compared to the lowest tertile (P for trend<0.05). Moreover, individuals in the top tertile of vitamin E had a lower prevalence of stress, in comparison to the bottom tertile (OR:0.34, 95 CI:0.13�0.89), (P for trend<0.05). However, no significant associations were found between the intakes of vitamin E and C and other psychological disorders. Conclusion: In this study, higher intake of β-Carotene was associated with lower prevalence of depression, anxiety and stress. Also, we found an inverse relationship between vitamin E intake and the risk of stress. © 2020 European Society for Clinical Nutrition and Metabolis

The association between nutrition knowledge and adherence to a Mediterranean dietary pattern in Iranian female adolescents

Adherence to a Mediterranean dietary pattern (MDP) has been reported to decrease chronic diseases. The aim of the present study was to determine the association between nutrition knowledge (NK) and adherence to MDP in Iranian female adolescents. This cross-sectional study was conducted on 297 female adolescents aged 15-18 years. The participants were interviewed using a valid and structured questionnaire to collect information on socio-demographic, lifestyle and anthropometric variables. Dietary intakes were assessed using a validated 168-item Food Frequency Questionnaire (FFQ). Adherence to MDP was measured by the Mediterranean-Style Dietary Pattern Score (MSDPS). Each participant's NK was determined using a 20-item NK questionnaire. The mean ± standard deviation (SD) age and body mass index (BMI) of participants were 16.1 ± 0.9 years and 22.3 ± 4.6 kg/m 2 , respectively. The median interquartile range (IQR) of the NK score and the MSDPS were 80.0 (68.0-87.0) and 15.2 (11.9-19.5), respectively. The odds ratio (OR) of higher adherence to MDP in the highest tertile of the NK score was 2.19 95% confidence interval (CI): 1.22-3.95; p for trend = 0.009, compared to the lowest tertile after adjusting for age and energy intake. In a multivariable-adjusted model, after further adjustment for BMI, mother's/father's education level, mother's/father's employment status, parent's marital status and physical activity, the subjects in the highest tertile of the NK score had higher adherence to MDP compared with those in the lowest tertile (OR = 2.05; 95% CI, 1.09-3.83; p for trend = 0.013). Our findings support the hypothesis that a higher NK score is significantly associated with a higher MDP adherence score in Iranian female adolescents. © 2019 Walter de Gruyter GmbH, Berlin/Boston

The association of dietary insulin and glycemic indices with the risk of type 2 diabetes

Background and aim: The aim of this study was to investigate the association of dietary insulin index(II), insulin load(IL), glycemic index(GI), and glycemic load(GL) with risk of developing diabetes among the Tehranian adults. Methods: This study was conducted within the framework of the Tehran Lipid and Glucose Study on 1149 subjects, aged �30 years, who were followed-up for a mean of 8.04 years. Food frequency questionnaire was used to calculate the dietary GI, GL, II, IL at the baseline. Multivariate Cox proportional hazard regression models, adjusted for the potential confounders, were used to estimate the risk of diabetes based on the dietary indices. Results: Mean age of the study population was 44.8 ± 10.4 years and 46.3 of them were men. During a mean of 8.04 ± 2.1 years of follow-up, 76 (6.6) new cases of diabetes were identified. The mean ± SD of the II, IL, GI, and GL of the participants were 52.4 ± 6.5, 234.9 ± 88.8, 61.8 ± 7.9, and 200.6 ± 74.5, respectively. After adjusting for age, sex, smoking, physical activity, daily energy intake, and body mass index, higher dietary scores of the IIHR = 1.33 (95%CIs = 1.06�1.68), ILHR = 1.70(95%CIs = 1.10�2.60), GIHR = 1.28(95%CIs = 1.03�1.60), and GLHR = 1.84 (95%CIs = 1.19�2.84) were found to be associated with the increased risk of diabetes incidence per each ones SD increment in the scores. Considering the tertiles of the dietary scores, the risk of developing diabetes was increased significantly from tertile 1 into 3 of the GL, and after adjusting for all the potential covariates (p-trend = 0.002); the diabetes risk was 3.40 (95%CI:1.48�7.83) in those with highest tertile of GL compared to those in the lowest tertile of GL. Conclusion: Our findings suggest that the diet with high GL, GI, II, and IL can increase the incidence of diabetes. The glycemic and insulin load can strongly predict the risk of diabetes rather than the glycemic index and insulin index. © 2020 Elsevier Ltd and European Society for Clinical Nutrition and Metabolis

Adherence to Mediterranean dietary pattern in female adolescents

Purpose: To the best of our knowledge, the studies on determining adherence to the Mediterranean dietary pattern (MDP) in Iran as a non-Mediterranean country are scarce. Thus, the aim of the study is to determine the adherence to the MDP in a sample of female adolescents who are residents of Tehran, Iran. Design/methodology/approach: In this cross-sectional study, 263 female adolescents aged 15-18 years were studied. Information on socio-demographic, lifestyle and anthropometric variables were obtained using a structured questionnaire. Also, dietary intakes were determined using a validated 168-item food frequency questionnaire. Adherence to MDP was characterized using Mediterranean-style dietary pattern score (MSDPS). Findings: Typically, the mean ± SD MSDPS was low in the present study (15.9 ± 5.6). The mean ± SD age and body mass index of the study population was 16.2 ± 0.9 years and 22.2 ± 4.1 kg/m2, respectively. In this study, the maximum MSDPS was 34.3, which was only one-third of maximum possible score (100). Multiple linear regression analyses showed that higher MSDPS scores were positively associated with age (standardized β = 0.1; p = 0.006), higher energy intake (standardized β = 0.2; p &lt; 0.001) and marginally higher physical activity (standardized β = 0.1; p = 0.079). Originality/value: Understanding low adherence to MDP in Tehranian female adolescents can provide basic knowledge to launch systematic programmes for gravitation toward MDP. © 2018, Emerald Publishing Limited