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Social cognitive theory (SCT) is a well-known theory for designing nutrition education and physical activity programs for adolescents. This systematic review aimed to evaluate the efficacy of intervention studies based on SCT in reducing or preventing overweight and obesity in adolescents. An electronic literature search in PubMed-Medline, Web of Science and Scopus was performed to identify intervention studies based on SCT aiming at preventing or reducing obesity in adolescents. All the articles published up to July 2016 were included. Only studies reporting body mass index (BMI) or its variant as one of the outcome measures were included. From 240 initially identified studies, 12 met the eligibility criteria. Seven had moderate or strong study quality. Two of the eight randomized controlled trials (RCT) and two of the four quasi-experimental studies showed significant reduction in BMI among intervened participants compared to control. Impacts on diet and physical activity were mixed, but were mostly not significant. The current systematic review found only weak evidence for the efficacy of SCT-based interventions in treating and preventing obesity in adolescents. Further studies systematically using effective behavior change strategies or techniques, larger population sizes, better measurement tools and more robust designs are warranted for a conclusive judgment.

Strenuous aerobic exercise is associated with oxidative stress and tissue damage. Therefore, we have investigated the effects of exercise and eicosapentaenoic acid supplementation, with or without vitamin E, on the plasma levels of vitamin C, E and A, IL-6, and glutathione peroxidase activity in basketball players. Thirty four male basketball players, enrolled in the study. Subjects received 2g EPA and/or 400 IU vitamin E or placebo depending on their groups. For 6 weeks, eight subjects took a daily EPA sup-plement together with vitamin E (group 1), nine received an EPA supplement together with placebo (group 2), nine were administered placebo along with vitamin E (group 3), and finally, eight subjects received placebo alone (group 4). As compared with group 4 (placebo), there were significant increases in vitamins C, E, and A in groups 1 and 3, but significant decreases in these parameters in group2 (P < 0.01). In addition, there were significant decreases in IL-6 in groups 1 and 3 (P < 0.01), whereas there were significant increases in glutathione peroxidase in groups1 and 3 (P < 0.01).There were significant differences in vitamin C between groups 3 and 4 (P < 0.05), and in vitamin E between groups 1 and 2, and groups 2 and 3 (P < 0.01), and in vitamin A between groups 1 and 2 (P < 0.05), and groups 1 and 4, 2 and 3, and 3 and 4 (P < 0.01), and in IL-6 between groups1 and 2 (P < 0.05), groups 1 and 3 (P < 0.01), 2 and 3 (P < 0.01), 2 and 4 (P < 0.01), and 3 and 4 (P < 0.05).

BACKGROUND: Alpha lipoic acid (ALA) is considered a strong antioxidant with anti-inflammatory properties. Moreover, a number of previous studies have shown its lipid-lowering properties. Therefore, we designed this study to investigate the effects of ALA on lipid profile in patients with metabolic syndrome (MetS), which can lead to an increased risk of cardiovascular disease (CVD) and premature mortality. METHODS: A total 46 patients with MetS were randomly divided into two groups. They received either 600 mg ALA (n = 23) or 600 mg placebo (n = 23) for 12 weeks. The body weight, height, body mass index (BMI), waist circumference (WC), fasting blood sugar (FBS), hemoglobin A1C (HbA1c), and blood pressure (BP) were assessed at baseline of the study. Physical activity level and dietary intake were assessed at baseline and end of the study. Serum lipid profile including triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and total cholesterol (TC) were measured before and after 12 weeks of intervention. RESULTS: Baseline characteristics were similar in the ALA and placebo groups (P > 0.05). However, there were statistically significant differences in plasma levels of TG (-36.82 ± 42.48 versus 6.15 ±25.04 mg/dl, P = 0.001) and TC (-8.91 ± 20.65 versus 10.84 ± 22.97 mg/dl, P = 0.01) after 12 weeks between the ALA group and the placebo group. Yet, there were no statistically significant differences in plasma levels of HDL-C and LDL-C after 12 weeks between the ALA group and the placebo group. CONCLUSION: The results suggest that daily supplementation of 600 mg ALA for 12 weeks may improve the lipid profile in patients with MetS. [ABSTRACT FROM AUTHOR]

Background: Evidence suggests that there is some relationship between circadian clock gene variants and obesity. However, there are few examinations supporting this observation in human subjects. This study was aimed to investigate the interaction between Cry1 circadian gene polymorphism and major dietary patterns on obesity measurements. Methods: Healthy overweight and obese women aged 18-53 years old were recruited from health centers in Tehran, Iran by a multistage cluster random sampling method (n = 377). Major dietary patterns were elicited after assessing the intake of 16 food groups using a valid and reliable 147-item food frequency questionnaire (FFQ). Anthropometric measurements were performed for each and every participant. Body composition was analyzed using bioelectrical impedance analysis (BIA). Socio-demographic and physical activity data were also collected by a validated Farsi demographic questionnaire and the international physical activity questionnaire (IPAQ). The Cry1 rs2287161 polymorphism were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Generalized linear models were used for interaction analysis. Results: Two major dietary patterns, including healthy and unhealthy dietary pattern (HDP and UDP, respectively) were determined using factor analysis. Our study showed a significant higher weight (P = 0.003), body mass index (BMI) (P = 0.042), hip circumference (P = 0.052), and body fat mass (P = 0.028) in carriers of C allele compared with G allele. Moreover, a significant gene-diet interaction was observed between being a carrier of C allele and BMI (P = 0.099 for CC genotype; P = 0.1 for CG genotype) and fat mass (P = 0.1 for CG genotype). Conclusions: The current study suggests a significant interaction of Cry1 rs2287161 gene polymorphisms in people following a healthy dietary pattern on BMI and fat mass among carriers of C allele compared to carriers of G allele. [ABSTRACT FROM AUTHOR]