Fast food consumption and its association with mental distress among Tibetan adolescents: a cross-sectional study

Although fast food consumption is linked to poor mental health among adolescents, evidence remains inconsistent overall and scarce among ethnic minorities, especially among Tibetan adolescents, who live in distinct sociocultural and environmental contexts and are experiencing rapid dietary transitions. This cross-sectional study was conducted between August 2023 and November 2024, and included 7,973 Tibetan students in grades 7–12 from seven public secondary schools in Lhasa, Xizang, China. Fast food consumption during the past month was assessed using a questionnaire item adapted from the Health Behavior in School-aged Children eating behavior module and categorized as less than once per week, once per week, and more than once per week. Mental distress was assessed using the 4-item Patient Health Questionnaire (PHQ-4), with outcomes defined as PHQ-4 clinical abnormality, depression symptoms, and anxiety symptoms. Logistic regression models with class-level cluster-robust standard errors were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for demographic, socioeconomic, sleep, physical activity, and school bullying factors. Among 7,973 Tibetan students, the mean age was 16.06 years, and 4,437 participants (55.65%) were girls. Overall, 5,056 students (63.41%) consumed fast food less than once per week, 2,020 (25.34%) once per week, and 897 (11.25%) more than once per week. The screening rates of PHQ-4 clinical abnormality, depression symptoms, and anxiety symptoms were 21.6%, 23.9%, and 25.2%, respectively. In adjusted models, fast food consumption more than once per week was associated with increased risk of PHQ-4 clinical abnormality (OR = 1.51, 95%CI: 1.27–1.80), depression symptoms (OR = 1.40, 95%CI: 1.18–1.67), and anxiety symptoms (OR = 1.35, 95%CI: 1.12–1.62). Sex-stratified analysis shows similar results, except for anxiety symptoms in females. Consuming fast food once per week was not significantly associated with any outcome. Frequent fast food consumption was associated with greater mental distress among Tibetan adolescents. These findings suggest that dietary behaviors may be relevant to adolescent mental health in high-altitude ethnic minority settings, and point to the need for culturally appropriate nutritional interventions in high-altitude ethnic minority regions of China.