Association between dietary zinc intake and asthma in overweight or obese children and adolescents: A cross-sectional analysis of NHANES.

Background: Asthma, characterized by recurrent wheezing, breathlessness, chest tightness, and coughing, is a major health concern among children and adolescents worldwide, currently affecting more than 5 million children. The increasing prevalence of obesity and overweight among the pediatric population has made the issue of childhood respiratory health more complex. Compared with children of healthy weight, the risk of asthma is higher in overweight and obese children. Zinc, a nutrient that regulates the oxidant-antioxidant balance, has been studied for its potential protective effects against asthma in adults and children. However, the results are controversial, with some studies reporting a beneficial effect and others showing no effect. Therefore, our objective was to assess the correlation between zinc intake from diet and asthma occurrence among children and adolescents who are overweight or obese. Methods: The National Health and Nutrition Examination Survey (NHANES) (2011-2020) provided data on individuals aged ≤20 who were overweight or obese, had asthma, and consumed zinc in their diet. The association between dietary zinc and asthma was evaluated using a variety of statistical methods, including multivariate logistic regression, restricted cubic spline analysis, and subgroup analysis. Results: A total of 4597 pediatrics and adolescents were enrolled, with 20.9% (963/4597) suffering from asthma. After adjusting for all covariates in the multivariate logistic regression, compared with the lowest zinc intake group Q1(≤5.68 mg/day), the adjusted OR values for zinc intake and asthma in Q2 (5.69-8.36 mg/day), Q3 (8.37-11.95 mg/day), and Q4 (≥11.96 mg/day) were 0.78 (95% CI: 0.62-0.98, p = 0.03), 0.76 (95% CI: 0.6∼0.98, p = 0.032), 0.71 (95% CI: 0.53∼0.95, p = 0.022), respectively. Stratified analysis showed no interactive role for dietary zinc intake and asthma in overweight or obese children and adolescents. Conclusions: Dietary zinc intake is inversely associated with asthma in overweight or obese children and adolescents.