Associations between antioxidant vitamin intake and mental health in Swedish adolescents: a cross-sectional study

Mental health problems are increasingly prevalent during adolescence. Nutritional factors, particularly antioxidants, are of interest due to their potential to reduce oxidative stress and inflammation linked to mental health issues. However, the relationship between dietary antioxidants and adolescent mental health remains unclear. This study aimed to investigate this association in Swedish adolescents and explore potential gender differences.

Cross-sectional data were gathered among Swedish boys and girls aged 13-14 years (n = 1139). Participants reported their dietary intake using a detailed web-based method and mental health outcomes, including anxiety, psychosomatic symptoms, and health-related quality of life (HRQoL) using self-report scales. Multiple linear regression analysis, adjusted for confounders, was used to investigate the associations between mental health outcomes and tertiles of dietary intake of vitamin C, E and β-carotene.

Adolescents in the highest tertile of β-carotene intake reported lower anxiety (β=-1.23, 95% CI=-2.34, -0.12), fewer psychosomatic symptoms (β=-0.91, 95% CI=-1.69, -0.13), and better HRQoL (β = 0.89, 95% CI = 0.11, 1.68). Similarly, higher vitamin C intake was associated with fewer psychosomatic problems (β=-1.00, 95% CI=-1.79, -0.21). Vitamin E intake showed no associations. Significant gender interactions were observed on the multiplicative scale analysis and limited to the middle tertiles of β-carotene and vitamin C for anxiety and psychosomatic symptoms, respectively.

Our findings underscore the potential role of dietary antioxidants, particularly β-carotene and vitamin C, in adolescent mental health. Further research including diverse populations and employing prospective designs could deepen the understanding and inform public health interventions.