Healthy dietary change could support adolescent mental health

07/02/2026 - Catrin Newman, Swansea University
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Healthy dietary change could support adolescent mental health

A study led by researchers at Swansea University suggests that dietary patterns may play a role in adolescent mental health, and sets out a detailed research roadmap to better understand this relationship. The review examined evidence from 19 studies exploring links between diet and mental health outcomes in adolescents. The work is published in the journal Nutrients.

Across the studies, healthier overall dietary patterns were often associated with fewer depressive symptoms, while poorer diet quality was linked to greater psychological distress.

The researchers analyzed six randomized controlled trials and 13 prospective cohort studies. They found that evidence supporting individual nutrient supplementation was mixed, with emerging but inconsistent findings that vitamin D supplementation may reduce depressive symptoms in adolescents. In contrast, whole-diet patterns and diet quality indices showed more consistent associations with favorable mental health outcomes.

The authors note that adolescence represents a critical period for brain development and mental health, offering opportunities for prevention and early intervention. Diet, they highlight, is a modifiable and scalable factor embedded in daily life. However, they caution that the current evidence base remains inconsistent and is influenced by demographic factors such as socioeconomic status and sex.

The review aimed to strengthen the real-world relevance of existing research by focusing beyond clinic-defined groups, with the goal of informing both clinical practice and public health policy.

The study also identifies significant gaps in the current literature. Most research to date has focused on depression, leaving outcomes such as anxiety, stress, externalizing behaviors, self-esteem and aggression comparatively underexplored.

To address these gaps, the authors present a detailed roadmap for future research, outlining recommended study designs, priority topics and methodological approaches. These include greater use of exposure-based studies, incorporation of biological markers, improved standardization, open science practices, and broader mental health outcome measures.

Corresponding author Professor Hayley Young of Swansea University's School of Psychology said, "Overall, our findings suggest that public health and clinical strategies should prioritize whole-diet approaches over isolated supplementation when considering adolescent mental health. However, further high-quality research is needed to determine which dietary patterns are most effective and for whom."