Associations between dietary behaviours and perceived physical and mental health status among Korean adolescents

Aim: To investigate the associations between a wide range of dietary behaviours and self-reported physical and mental health status in a representative sample of Korean adolescents. Methods: Data from the 2016 Korea Youth Risk Behaviour Web-based Survey were used. Participants were middle-and high-school students (n = 65 528) in grades 7-12. Participants' dietary behaviours were assessed using questionnaires on three encouraged dietary behaviours (consumption of fruits, vegetables, and milk) and three discouraged behaviours (skipping breakfast and consumption of fast food and soft drinks). Participants were also asked to rate their perceived general and oral health, happiness, sleep satisfaction, stress, depressed mood, and suicidal ideation. Results: After adjusting for sex, school grade, residential area, socioeconomic status, and other dietary behaviours, a high intake of fast food and soft drink and frequent skipping of breakfast were all associated with worse physical and mental health status. Moreover, a high intake of fruits, vegetables, and milk were associated with better perceived general health, oral health, happiness, and sleep satisfaction. Conclusions: Our data suggest that existing encouraged dietary habits mostly have beneficial effects on perceived physical and mental health in Korean adolescents. However, the cross-sectional study design prevents our ability to assess causal relationships.