Factors related to overweight among students in remote service areas of Northern Thailand: the structural equation model

Although the causal relationships of personal, behavioral, and environmental factors related to overweight in adolescents have been studied, there is limited evidence in northern Thailand. This study aimed to investigate the causal relationships of these factors among high school students in Health Region 1, northern Thailand. The study was conducted between November 2021 and March 2022 among 2,250 high school students. A multi-stage sampling method and structural equation modeling (SEM) were used to investigate the causal relationships between personal, behavioral, and environmental factors and overweight. Most participants were female (60.6%) with an average age of 17.0 years, free from chronic illnesses (96.3%), of LANNA ethnicity (56.8%), having moderate dietary habits (48.1%) and insufficient physical activity (83.0%). Weight and height were directly correlated with overweight. Similarly, a causal relationship was observed between dietary behavior (snacks, sweets, fast food, and condiments) (p <0.05), and physical activity (incorporating exercise and sports, recreational activities, screen time, and sedentary behaviors) (p <0.001). The model’s goodness-of-fit indices indicated an acceptable fit (χ² = 262.356, df = 59, P = 0.082, χ²/df = 1.65, RMSEA = 0.017, SRMR = 0.026, CFI = 0.984, TLI = 0.979), which can explain the variance = 72.27 %. In conclusion, dietary behaviors, particularly the consumption of snacks, sweets, fast food, and condiments, as well as physical activity were important factors for being overweight in high school students. These findings can serve as essential knowledge for policy development to promote interventions for improving nutritional status in adolescents.