Association between dietary acid load and metabolic health status in overweight and obese adolescents

The relationship between dietary acid load (DAL) and metabolic health status in adolescents has not been studied yet. We aimed to examine the association between DAL and metabolic health status in Iranian overweight/obese adolescents. This cross-sectional study included 203 overweight/obese adolescents selected by a multistage cluster random sampling method. Dietary intakes were assessed using a validated 147-item food frequency questionnaire (FFQ). Anthropometric indices and blood pressure values were measured. Fasting blood samples were obtained to determine glucose, insulin, and lipid profiles. Based on two methods (International Diabetes Federation (IDF) criteria and combination of IDF with Homeostasis Model Assessment Insulin Resistance (HOMA-IR)), participants were classified into metabolically healthy obese (MHO) or unhealthy obese (MUO). Adolescents in the highest tertile of potential renal acid load (PRAL) and net endogenous acid production (NEAP), compared with those in the lowest tertile, had 172% (95% CI 1.32-5.59) and 161% (95% CI 1.26-5.41) higher odds of MUO status, based on IDF criteria. This association was significant after adjustment for age, sex, and energy intake (PRAL: OR 2.42; 95% CI CI 1.13-5.15; NEAP: OR 2.52; 95% CI 1.17-5.41); but it disappeared after adjustment for other confounders. Based on IDF/HOMA-IR definition, there was a significant positive association between PRAL and being MUO only in the crude model (OR 2.37; 95% CI 1.13-4.96). The stratified analysis revealed that these associations for NEAP scores were stronger among overweight subjects than obese individuals, based on both metabolic status definitions. However, after adjustment for all potential confounders these relations were insignificant. Having higher DAL might be associated with higher odds of MUO phenotype in Iranian overweight/obese adolescents. More prospective studies are warranted to confirm this finding.