Abstract

The double burden of malnutrition and nutrient inadequacy, characterized by the coexistence of underweight or excess body weight, is increasingly prevalent among adolescents in low-and middle-income countries, including Thailand. This study aimed to determine the prevalence of this double burden and to identify sociodemographic predictors of nutrient inadequacy among Thai secondary school adolescents. This cross-sectional survey was conducted in one province of Southern Thailand with 1,205 students, aged 13–18 years. Sociodemographic data were collected through a self-administered questionnaire. Nutritional status was assessed using World Health Organization Body mass index-for-age z-scores, while dietary intake was measured through 24-hour dietary recalls. Nutrient adequacy was evaluated according to the Thai Recommended Dietary Intakes. Chi-square tests and multiple binary logistic regression analyses were applied to examine associations between sociodemographic variables and nutrient inadequacy. Results showed the prevalence of thinness and excess body weight was 24.2% and 23.1%, respectively. Inadequate intake of calcium, vitamin C, zinc, selenium, and magnesium exceeded 95% in all groups. Predictors of nutrient inadequacy included breakfast skipping, large family size, male gender, younger age, and physical inactivity. The f indings highlight that Thai adolescents face widespread micronutrient def iciencies regardless of weight status. School and community-based interventions tailored to age and gender are needed to address the double burden of malnutrition by collaborating with school health educators to improve screening, nutritional knowledge, advocate for school food policies, and foster healthy environments.