Hidden nutritional inadequacy in U.S. children with obesity: Evidence from National Health and Nutrition Examination Survey 2021-2023.

BACKGROUND

Childhood is a critical period of growth and development with high nutritional demands, yet many U.S. children do not meet recommended nutrient intakes. This study assessed obesity prevalence, dietary intake, and vitamin D status among U.S. children aged 3-11 years.

METHODS

This brief report used cross-sectional data from the National Health and Nutrition Examination Survey (NHANES) collected between August 2021 and August 2023. Children aged 3-11 years with dietary and anthropometric data and no reported dietary supplement use were included (n = 544). Obesity was defined as body mass index (BMI) at or above the 95th percentile for age and gender. Dietary intake was assessed using first-day 24-h dietary recall data. Survey-weighted generalized linear models adjusted for age, gender, and race/ethnicity were used to compare dietary intake and vitamin D biomarkers between children with and without obesity.

RESULTS

The prevalence of obesity was 20.1% (95% confidence interval (CI): 16.8-23.4). Children with and without obesity consumed similar amounts of total energy, protein, carbohydrate, fat, and vitamin D (all P > 0.05). However, children with obesity had significantly (P ≤ 0.05) lower protein intake relative to body weight and more than fivefold higher odds of consuming protein below the Estimated Average Requirement (odds ratio (OR) 5.15, 95% CI 2.76-9.62; P < 0.001). Children with obesity also had significantly lower circulating vitamin D concentrations (25-hydroxyvitamin D2 + D3 <50 nmol/L) and more than threefold higher odds of low vitamin D status (OR 3.41, 95% CI 1.89-6.17; P < 0.001).

CONCLUSION

Among U.S. children aged 3-11 years, obesity was associated with lower protein intake relative to body weight and poorer vitamin D biomarker status despite similar absolute dietary intake. These findings suggest that children with obesity may be at increased risk of hidden nutritional inadequacy and highlight the importance of additional nutritional monitoring and individualized care.