One of the major epidemiologic public health problems is worldwide metabolic syndrome (MetS). Since the relationship between diet quality and MetS among adolescents in developing countries has not been well understood, the present study aimed to evaluate the association between diet quality, as measured by Healthy Eating Index (HEI-2005) and the prevalence of MetS and its risk factors in a group of Tehranian adolescents. This crosssectional study was conducted on 706 adolescents, aged 10-19 years, within the framework of Tehran Lipid and Glucose Study in 2008-2011. Usual dietary intakes were assessed by valid and reliable semi-quantitative food frequency questionnaire and diet quality score was obtained based on HEI-2005. MetS was determined using the modified de Ferranti definition. There were 706 adolescents, aged 14.8±2.7 years. The overall prevalence of MetS in adolescents was 22.4%. Large waist circumference was the most common component of MetS in both girls and boys. After adjusting for age, sex, energy intake and physical activity, participants who were in the highest quartile of HEI-2005 compared with lowest quartile had lower prevalence of hypertriglyceridemia (OR: 0.62; CI 95%: 0.40-0.96 and P for trend= 0.02), and low serum HDL-C (OR: 0.62; CI 95%: 0.41-0.97 and P for trend= 0.02). No significant difference was observed in odds of MetS, large waist circumference, hyperglycemia and hypertension. Adolescents with dietary pattern more consistent with the HEI-2005, had lower prevalence of hypertriglyceridemia and low serum HDL-C.

Obesity has become a public health problem in adolescents and could be a risk factor for both short-term and long-term health consequences. This study aimed to evaluate the relationship of Dietary Guidelines for Americans Adherence Index (DGAI), Healthy Eating Index-2005 (HEI-2005) and Healthy Eating Index-2010 (HEI-2010) with risk of obesity associated phenotypes in Tehranian adolescents. This cross-sectional study was conducted within the framework of the Tehran Lipid and Glucose Study, on 722 adolescents, aged 10–19 years. Usual dietary intakes were assessed by a food frequency questionnaire, and diet quality scores were obtained based on DGAI, HEI-2005 and HEI-2010. General obesity and cardio metabolic risk factors were defined according to the Centers of Disease Control and Prevention and de’Ferranti cut-offs, respectively. After adjusting for age, sex, energy intake and physical activity, compared to those in the lowest quartile, participants in the highest quartile of HEI-2010 had lower risk of general obesity (OR: 0.62; 95% CI: 0.38–0.93; Ptrend = 0.03) and central obesity (OR: 0.63; 95% CI: 0.44–0.95; Ptrend = 0.04). No association was observed between different types of obesity and scores of other diet quality indices. In conclusions, considering the role of HEI-2010 in decreasing the risk of obesity, these findings suggest that HEI-2010 may be useful for assessing diet-related progress in obesity prevention efforts.

Dyslipidemia is an important risk factor for cardiovascular disease (CVD) and an important cause of death in adults. Long-term follow-up studies have demonstrated that dietary fat consumption in children and adolescent is one of these risk factors of dyslipidemia in adulthood. The purpose of the current study was to assess the dietary fat intake of Iranian adolescents and their relationship with serum lipid profiles. In this population based cross-sectional study 717 adolescents (391 girls and 326 boys), aged 10 to 19 years, were randomly selected from the fourth phase of Tehran Lipid and Glucose Study (2008)(2009)(2010)(2011). Usual dietary intakes were assessed using valid and reliable food frequency questionnaire and a fasting blood sample was given from all participants to analyze serum lipid profile. Among serum lipid levels, only triglyceride (TG) concentration was higher significantly in boys. In girls, the percent of energy intake from total fat, poly unsaturated fatty acid (PUFA), mono unsaturated fatty acid (MUFA) and trans fatty acids were higher significantly. After adjustment for sex and age, serum levels of TG and HDL-C showed a significant decreasing and increasing trend according to the quartiles of percent of energy intake from PUFA, respectively. No significant difference was observed between other fatty acids and serum lipid profile. In conclusion, although the percent of calorie intake from fat and different types of fatty acids have effect in determining serum lipids levels, but they are not the most important factors for determining the serum lipid profile.