Dietary approaches to stop hypertension (DASH) score and obesity phenotypes in children and adolescents

BACKGROUND: The prevalence of obesity and its two important phenotypes, the metabolically healthy obese (MHO) and the metabolically unhealthy obese (MUO) are 10.9, 9.1, and 1.8%, respectively, among children and adolescents in Iran. Data on the link between diet quality indices and obesity phenotypes in children and adolescents is scarce. The present study aimed to assess the association of the Dietary Approaches to Stop Hypertension (DASH) score with MHO and MUO, as well as with cardiometabolic risk factors (RFs) in children and adolescents with excess weight. METHODS: This cross-sectional study was conducted on 341 children and adolescents with excess weight aged 6–13 years, selected from primary schools of Tehran. The DASH score was determined based on eight components using a valid and reliable food frequency questionnaire. Anthropometric measures, insulin, fasting plasma glucose, lipid profile, and physical activity levels were collected. MUO was classified based on two definitions: having 2 or more cardiometabolic RFs, or being insulin resistant determined by a homeostatic model assessment of insulin resistance (HOMA-IR) ≥ 3.16. Multivariable logistic regression models were used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for MUO phenotypes and cardiometabolic RFs in each tertile of the DASH score after adjustment for confounders. RESULTS: The mean ± SD for age and DASH score was 9.3 ± 1.7 years and 24.0 ± 4.9, respectively. The prevalence of MUO was 62.2% based on RFs, and 43.4% based on HOMA-IR. Participants in the highest tertile of the DASH score had significantly decreased odds for MUO based on HOMA-IR (OR = 0.49; 95% CI: 0.28–0.87) compared with those in the lowest tertile, after adjustment for confounders. However, there were no associations between the DASH score and any of cardiometabolic RFs, or MUO based on RFs (OR = 0.68; 95% CI: 0.38–1.20). CONCLUSION: The DASH score was inversely associated with MUO based on HOMA-IR, but not associated with MUO based on cardiometabolic RFs in this sample of children and adolescents. A DASH-style diet may have favourable effects on insulin sensitivity among children and adolescents with excess weight. Universal definitions for MHO/MUO are required, and longitudinal studies recommended to shed light upon this subject.