Amelia A. Martí del Moral

Effects of the FTO Gene on Lifestyle Intervention Studies in Children

The effects of FTO on body weight, body composition, and the risk of developing overweight and obesity in children, adolescents, and adults are analyzed in this review. Most trails have been conducted on the rs9939609 SNP of the FTO gene. The minor A-allele frequency ranged from 0.38 to 0.49 in different European populations. Briefly, it has been reported that overweight-obesity risk per A-allele ranged from 1.76 to 1.35, whereas z-score for BMI has a wider variation from 0.05 to 0.5 kg/m2 in European children and adolescents. As for other adiposity indexes, a waist circumference increase from 0.60 to 0.95 cm per A-allele was found together with an increase in fat mass from 0.68 to 1.78 kg in European children and adoles-cents. In regard to food intake, AA carrier subjects were reported to have reduced satiety responsiveness scores and a higher total energy and fat intake. However, it is not clear whether energy expenditure did modify the role of the rs9939609 FTO gene variant in adiposity. Furthermore, few reports examined the influence of FTO gene variants using intervention studies. Overall, it seems that the A-allele (rs9939609 FTO) is associated with higher body weight gain. However, further studies into FTO gene variants in children and adults are needed.

Anthropometric indices to assess body-fat changes during a multidisciplinary obesity treatment in adolescents: EVASYON Study.

BACKGROUND & AIMS The main objectives of weight loss interventions in children and adolescents are to decrease fat mass while maintaining fat-free mass. Several methods are available to assess childhood and adolescence obesity, such as weight and height, bioelectrical impedance, skin-fold thickness measurements and other laboratory methods. The aim was to assess simple anthropometric indices as predictors of body-fat changes, using dual-energy X-ray absorptiometry measurements as reference method. METHODS Multi-intervention approach (diet, physical activity and psychological support in a family-group-based treatment) was implemented with a one-year follow-up in 13-to-16-year-old overweight or obese Spanish adolescents. A total of 83 adolescents were recruited from Granada and Zaragoza, males (n = 43) (31.6 kg/m(2)) and females (n = 40) (32.0 kg/m(2)). We measured body composition with anthropometry and dual-energy X-ray absorptiometry. All measurements were made at baseline, and after 2 and 13 months. Random coefficient regression model was used to calculate the proportion of body composition changes during follow-up that would be explained by simple body composition indices based on anthropometric measures. RESULTS After controlling for age and Tanner stage, body mass index explained 76.5% of body composition changes in males and 90.1% in females, while fat mass index (assessed by skin-folds) explained 78.9% of body composition changes in males and 84.0% of body composition changes in females. CONCLUSIONS In conclusion, we found that BMI was a good indicator of body fat composition changes in children and adolescents, although FMI assessed by anthropometry was also a good indicator.