Association of dietary behaviour and depression among adolescents in Malaysia: a cross-sectional study

Background Depression is on the rise and has become a significant concern for public health. Limited research has explored the connection between dietary patterns and depression. This investigation aimed to examine how dietary behaviours relate to depression among adolescents attending school in Malaysia. Methods The study utilized data from the National School-Based Health Survey 2022, a nationwide survey involving school-going adolescents aged 13–17, with a total of 33,523 participants from 239 schools. To assess depression, the study employed the Patient Health Questionnaire (PHQ-9), considering a score of 10 or higher as indicative of depression. Dietary behaviours were assessed using a validated self-administered questionnaire adapted from the World Health Organization's Global School-based Student Health Survey. Descriptive analysis and complex sample logistic regression were carried out using SPSS version 26.0. Results The study revealed a 26.9% overall prevalence of depression, with higher risks among female adolescents (AOR 2.71, 95% CI 2.51, 2.92) and those in higher grades. Malays (AOR 1.71, 95% CI 1.41, 2.07), Other Bumiputeras (AOR 1.69, 95% CI 1.32, 2.17), and Others (AOR 1.63, 95% CI 1.16, 2.30) had elevated odds of depression compared to Indians. Healthy dietary habits, like consuming less than two servings of fruits daily, correlated with depression (AOR 1.44 95% CI 1.35, 1.54). Additionally, unhealthy dietary behaviours such as fast food consumption (AOR 1.73 [95% CI 1.55, 1.93]) and carbonated soft drink intake (AOR 1.59 [95% CI 1.48, 1.70]) were positively associated with depression. Conclusions One out of every four Malaysian adolescents was identified to experience depression. Depression was linked to several factors, such as being female, belonging to higher grade levels, identifying as Malays, Other Bumiputeras, or belonging to other ethnicities, and participating in the consumption of fast food, carbonated soft drinks, and fruits. To address these observations, it is crucial to formulate effective public health programmes that prioritize adolescent mental health and encourage the adoption of healthy eating habits.