Is there any relationship between dietary patterns and depression and anxiety in Chinese adolescents?

OBJECTIVE To determine the association between major dietary patterns characterized by factor analysis and risk of depression and anxiety symptoms among adolescents. DESIGN Diet and symptoms of depression and anxiety were assessed in a cross-sectional survey among students attending junior high school. Dietary patterns were derived from a self-reported FFQ, which consisted of thirty-eight items. Anthropometric measurements were also performed. SETTING Four junior high schools in Bengbu city, China. SUBJECTS A random sample of 5003 adolescents, 11-16 years of age (mean 13·21 years). RESULTS Three major dietary patterns were identified in the study based on factor analysis: 'snack', 'animal food' and 'traditional'. The prevalence of depression symptoms, anxiety disorders and the coexistence of both were 11·2% (560/5003), 14·6% (732/5003) and 12·6% (629/5003), respectively. After adjustment for potential confounders, adolescents in the highest tertile of snack dietary pattern scores had a higher odds for 'pure' psychological symptoms ('depression without anxiety', OR = 1·64; 95% CI 1·30, 2·06; and 'anxiety without depression', OR = 1·87; 95% CI 1·51, 2·31) compared with coexisting depression and anxiety (OR = 1·93; 95% CI 1·54, 2·43). Similar to snacks, high consumption of animal foods was associated with a higher risk of psychological symptoms. Compared with low consumption, adolescents in the highest tertile of traditional dietary pattern scores had lower odds for 'pure' depression (OR = 0·38; 95% CI 0·30, 0·49), 'pure' anxiety (OR = 0·85; 95% CI 0·69, 1·04) and coexisting anxiety and depression (OR = 0·50; 95% CI 0·39, 0·63). CONCLUSIONS Data from Chinese secondary-school adolescents validated findings from adult populations. Dietary patterns should be considered as important predictors of depression and anxiety among adolescents in further studies.