Combined effect of unsaturated fatty acids and saturated fatty acids on the metabolic syndrome: tehran lipid and glucose study

Aims: The aim of this study was to investigate whether the background intakes of total dietary fat, monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) modulate the effects of dietary saturated fatty acids (SFA) on metabolic syndrome (MetS). Material and Methods: This population-based cross-sectional study was conducted on a representative sample of 4 677 adults, aged 19 to 84 years. MetS was defined according to the ATP III criteria. Results: Median intakes of SFA, MUFA and PUFA were 9.5, 9.6 and 5.6% of total energy. High SFA intakes were associated with higher prevalence of MetS, in both individuals with higher and lower median intakes of total fat, MUFA and PUFA. Conclusions: Our findings indicate that SFA intakes were positively associated with the prevalence of MetS, independent of total dietary fat, MUFA and PUFA intake

اخلاق در مطالعات بر مبنای جامعه

Background and Aim: Community-based research has a heavier ethical mission than other research because it has to figure out how to better address health issues in the population under study, while protecting the rights of the population under study. The purpose of this study is to examine the ethics of community-based research and its observance at different levels of society, staff and participants. Materials and Methods: This article searched the databases of Web of science, PubMed, Scopus, google scholar, Magiran, SID with keywords in ethics, community based studies and population based studies. Findings: Five ethical principles that must be considered in community-based research include: 1. Protecting the health and well-being of populations; 2. Respecting populations and their right to decide on themselves; (3. Protecting The vulnerable population and the need for specific research inquiries; 4. The protection of confidential information, the integrity, and respect for populations; 5. The fair distribution of the benefits of research into populations and the importance of infrastructure creation. These ethical principles must be taken into account at three levels of larger communities in which research is conducted (host societies), field staff and participants in the research. Ethical Considerations: Honesty and trustworthiness were observed in reporting articles and the findings of these articles were stated without bias. Conclusion: Research ethics, such as delivering results to the community, enable the community to actively participate in the development of community-based research.   Cite this article as: Hosseinpour-Niazi S, Mirmiran P. Ethics in Community-Based Studies. Med Ethics J 2020; 14(45): e1.زمینه و هدف: پژوهش بر مبنای جامعه، مأموریت اخلاقی سنگین‌تری نسبت به سایر پژوهش‌ها دارد، زیرا باید به این نتیجه برسد که چگونه می‌توان با روش بهتری مشکلات مربوط به سلامتی در جمعیت مورد پژوهش را بهبود بخشید و در عین ‌حال از حقوق جمعیت مورد مطالعه خود حفاظت کرد. هدف از این مطالعه بررسی اصول اخلاقی در پژوهش‌های بر مبنای جامعه و رعایت آن در سطوح مختلف جامعه، کارکنان و شرکت‌کنندگان است. مواد و روش‌ها: این مقاله مروری پایگاه‌های اطلاعاتی Web of Science، Pubmed، Scopus، Google Scholar، بانک اطلاعات نشریات ایران (Magiran)، پایگاه مرکز اطلاعات علمی جهاد دانشگاهی (SID) با واژگان کلیدی Ethic و Community Based Studies و Population Based Studies جستجو شد. یافته‌ها: پنج اصل اخلاقی که باید در پژوهش‌های بر مبنای جامعه در نظر گرفته شود، شامل 1ـ محافظت از سلامتی و تندرستی جمعیت‌ها؛ 2ـ احترام به جمعیت‌ها و حق آن‌ها در رابطه با تصمیم‌گیری برای خود؛ 3ـ حفاظت از جمعیت آسیب‌پذیر و لزوم توضیحات ویژه در مورد پژوهش؛ 4ـ حفاظت از اطلاعات محرمانه، یکپارچگی و محترم‌شمردن جمعیت‌ها؛ 5ـ توزیع عادلانه فواید حاصل از تحقیق در جمعیت‌ها و اهمیت ایجاد زیرساخت‌ها. این اصول اخلاقی باید در سه سطح شامل جوامع بزرگ‌تر که در آن‌ها پژوهش اجرا می‌شود (جوامع میزبان)، کارکنان و شرکت‌کنندگان در پژوهش لحاظ شود. ملاحظات اخلاقی: صداقت و امانتداری در گزارش مقالات رعایت شد و یافته‌های حاصل از این مقالات بدون سوگیری بیان شد. نتیجه‌گیری: رعایت اخلاق در پژوهش مانند ارائه نتایج به جامعه سبب مشارکت فعال جامعه در پیشرفت پژوهش‌های مبتنی بر جامعه می‌شود

Prospective Study of Nut Consumption and Incidence of Metabolic Syndrome: Tehran Lipid and Glucose Study

This study aimed to assess the association of various types of nut per se, and total nut consumption with the incidence of metabolic syndrome (MetS). A 6.2 ± 0.7-year population-based prospective study was conducted among 1265 adults, aged 19–74 years, participants of the Tehran Lipid and Glucose Study. A 168-item semi-quantitative food frequency questionnaire was used to collect information on nut consumption. MetS was defined according to the Joint Interim Statement guidelines and 276 new cases of MetS were identified. Median ± interquartile range of nut consumption was 2.08 (0.88–5.68) servings/week. After adjusting for family history of diabetes, age, gender, smoking, physical activity, fasting serum glucose at baseline, serum high density lipoprotein cholesterol (HDL-C) at baseline, energy intake, fiber, macronutrients, cholesterol intake, fruit, vegetables, dairy products and body mass index (BMI), a statistically significant decrease was observed in MetS in the third (≥5 servings/week) tertile of nuts (odds ratio: 0.68, 95% CI: 0.44–0.91, p trend: 0.03) compared with the lowest (≤1 serving/week). Walnut consumption showed a significant, inverse association with MetS risk; associations for other nut varieties were not significant. For each additional serving/week of walnuts consumed, incidence of MetS decreased by 3% (ORs: 0.97 CI: 0.93–0.99), after adjusting for confounding factors. Total nut consumption, especially walnuts, reduces the 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

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

Abstract 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

Dietary fructose and risk of metabolic syndrome in adults: Tehran Lipid and Glucose study

<p>Abstract</p> <p>Background</p> <p>Studies have shown that the excessive fructose intake may induce adverse metabolic effects. There is no direct evidence from epidemiological studies to clarify the association between usual amounts of fructose intake and the metabolic syndrome.</p> <p>Objective</p> <p>The aim this study was to determine the association of fructose intake and prevalence of metabolic syndrome (MetS) and its components in Tehranian adults.</p> <p>Methods</p> <p>This cross-sectional population based study was conducted on 2537 subjects (45% men) aged 19-70 y, participants of the Tehran Lipid and Glucose Study (2006-2008). Dietary data were collected using a validated 168 item semi-quantitative food frequency questionnaire. Dietary fructose intake was calculated by sum of natural fructose (NF) in fruits and vegetables and added fructose (AF) in commercial foods. MetS was defined according to the modified NCEP ATP III for Iranian adults.</p> <p>Results</p> <p>The mean ages of men and women were 40.5 ± 13.6 and 38.6 ± 12.8 years, respectively. Mean total dietary fructose intakes were 46.5 ± 24.5 (NF: 19.6 ± 10.7 and AF: 26.9 ± 13.9) and 37.3 ± 24.2 g/d (NF: 18.6 ± 10.5 and AF: 18.7 ± 13.6) in men and women, respectively. Compared with those in the lowest quartile of fructose intakes, men and women in the highest quartile, respectively, had 33% (95% CI, 1.15-1.47) and 20% (95% CI, 1.09-1.27) higher risk of the metabolic syndrome; 39% (CI, 1.16-1.63) and 20% (CI, 1.07-1.27) higher risk of abdominal obesity; 11% (CI, 1.02-1.17) and 9% (CI, 1.02-1.14) higher risk of hypertension; and 9% (CI, 1-1.15) and 9% (1.04-1.12) higher risk of impaired fasting glucose.</p> <p>Conclusion</p> <p>Higher consumption of dietary fructose may have adverse metabolic effects.</p

Pre-Pregnancy Fast Food Consumption Is Associated with Gestational Diabetes Mellitus among Tehranian Women

The aim of this study was to evaluate the association between fast food consumption and gestational diabetes mellitus (GDM) among Tehranian women. This study was conducted over a 17-month period, on a random sample of pregnant women (n = 1026), aged 18–45 years, attending prenatal clinics in five hospitals affiliated with universities of medical sciences, located in different districts of Tehran, Iran. Dietary data were collected during gestational age ≤6 weeks, using a 168-item valid and reliable food frequency questionnaire. Consumption of total fast foods including hamburgers, sausages, bologna (beef), pizza and French fries was calculated. Between 24 and 28 weeks of gestation, all pregnant women underwent a scheduled 100 g 3 h oral glucose tolerance test. GDM was defined according to the American Diabetes Association definition. The mean age and pre-pregnancy body mass index BMI of participants were 26.7 ± 4.3 years and 25.4 ± 4.5 Kg/m2, respectively. A total of 71 women developed GDM. After adjustment for confounders, the OR (95% CI) for GDM for total fast food consumption was 2.12 (1.12–5.43) and for French fries it was 2.18 (1.05–4.70). No significant association was found between hamburgers, sausages, bologna (beef), pizza and GDM. Fast food consumption in women of reproductive age was found to have undesirable effects in the prevalence of GDM