Diet quality and feelings of worry, sadness or unhappiness in Canadian children.

OBJECTIVE: To examine the association between diet quality and feelings of worry, sadness or unhappiness in Canadian children.
METHODS: Responses to the Harvard Food Frequency Questionnaire of 6,528 grade 5 students were used to calculate a composite score of diet quality, and its components: variety, adequacy, moderation and balance. Responses to the question on "feelings of worry, sadness or unhappiness" from the EuroQoL 5 Dimension questions for Youth (EQ-5D-Y), a validated Health Related Quality of Life questionnaire, constitute the outcome of interest. Multilevel logistic regression methods were used to examine the association between diet quality and feelings of worry, sadness or unhappiness. All analyses were adjusted for gender, household income, parental education, energy intake, weight status, physical activity level, geographic area and year of data collection.
RESULTS: Diet quality was inversely associated with children's feelings of worried, sad or unhappy (Odds ratio (95% confidence interval): 0.90 (0.85-0.97)). Dietary variety and dietary adequacy were also statistically significantly associated with lower odds of feeling worried, sad or unhappy. When the results were stratified by gender, the effect of diet on feeling worried, sad or unhappy was more pronounced in girls than boys.
CONCLUSION: These findings suggest that diet quality plays a role in feelings of worry, sadness or unhappiness and complement other studies that have suggested the link between diet and mental health. We recommend consideration of diet quality in public health strategies that aim to reduce the burden of poor mental health in children and youth.