Dietary Patterns Exhibit Sex-Specific Associations with Adiposity and Metabolic Risk in a Cross-Sectional Study in Urban Mexican Adolescents.

Background: Studies in Western nations have shown associations of certain dietary patterns with obesity and metabolic risk in youth. Little is known about these relations in newly industrialized countries where obesity prevalence is surpassing those of developed countries.Objective: We sought to characterize dietary patterns in a cross-sectional study in 224 adolescents aged 8-14 y in Mexico and to investigate associations of the dietary patterns with adiposity and metabolic risk.Methods: We used principal components analysis to derive dietary patterns from food-frequency questionnaire data. By using linear regression models that accounted for mother's marital status, education, and smoking habits and child's age and physical activity, we examined associations of the dietary patterns with adiposity [body mass index z score, waist circumference, the sum and ratio of the subscapular and triceps skinfold thicknesses, blood pressure, serum fasting glucose and a C-peptide-based measure of insulin resistance (CP-IR), lipid profile, and a metabolic syndrome risk z score (MetS z score)].Results: We identified a "prudent" dietary pattern characterized by high intakes of vegetables, fruit, fish, chicken, and legumes and a "transitioning" dietary pattern, which comprises processed meats, Mexican foods, and sweetened beverages. Each unit increase in the prudent pattern factor score corresponded with 0.33 ng/mL (95% CI: 0.09, 0.57 ng/mL) lower C-peptide, 0.08 units (95% CI: 0.02, 0.13 units) lower CP-IR, and a 0.14 unit (0.00, 0.27 unit) lower MetS z score in boys. In girls, the transitioning pattern corresponded with higher subscapular + triceps skinfold thickness (per 1-unit increase in the factor score: 2.46 mm; 95% CI: 0.10, 4.81 mm). These results did not change after accounting for pubertal status.Conclusions: A prudent dietary pattern was protective against metabolic risk in adolescent boys, whereas a transitioning dietary pattern corresponded with higher adiposity among adolescent girls. Given that adolescence is a key developmental period for long-term health, efforts to elucidate dietary determinants of metabolic risk during this life stage may have long-term benefits.