Diet, Exercise and Mental Health

Media reports suggest a growing student mental health crisis. Is this an inevitable response to the challenges young people face in 21st century Britain – or are there ways of reducing mental health risks?

And might a 2000-year-old analysis help here? The Roman poet Juvenal wrote, ‘Mens sana in corpore sano’ – a healthy mind in a healthy body. This suggests that action to improve our physical health could also help our mental health – for example through a healthy diet and through exercise/physical activity. Here’s what modern research suggests:

A healthy diet

Khalid et al undertook a systematic review of published research, in 2017.1 This reported significant associations between a healthier diet – broadly defined as positive eating behaviours, consumption of fruit and vegetables, and avoiding typically ‘unhealthy foods’ - and lower depression. Similarly, all the studies in the review found significant associations between ‘unhealthy diets’ and depression, with one study in particular reporting an unhealthy diet can predict the occurrence of depression two years later. In addition, junk food and snacking between meals was found to be associated with increased odds of mental health problems. Interestingly the negative implications of following an unhealthy dietary pattern (like excessive junk food) on depression and anxiety is frequently reported.2,3

These findings are in line with previous research that indicates a healthy regular eating pattern may play a protective role in the overall mental health of young adults –and even just one aspect can have a significant protective effect. For example, O’Sullivan et al compared skipping breakfast entirely to a breakfast comprising foods such as high fibre cereal and fruit with orange juice and/or milk.4 This suggested a possible dose-response relationship between increased breakfast quality and improved mental health in adolescents.

Physical activity/exercise

A range of evidence also links physical activity and exercise with improvements in mental health. One study found that with increased levels of physical activity significant reductions in depression, anxiety, psychological distress, and emotional disturbance in children was evident, with a combination of aerobic and resistance type exercise having the greatest effect.5 Conversely, less physically demanding activities like yoga seemingly have little impact on mental health symptoms.6 A study from Chekroud et al reporteded that individuals who exercised between 30 and 60 mins, 3-5 times per week had around 1.5 (43%) fewer days of poor mental health per month compared to individuals who did not exercise.7 Popular team sports, cycling and aerobic and gym activities provided the greatest benefit. Interestingly, more is not always better, as engaging in exercise more than 23 times per month or longer than 90 mins was associated with worse mental health. A recent systematic review has highlighted the sustained benefits of exercise interventions with a suggestion of exercising for around 6 months being beneficial, although admittedly larger follow-up studies would be beneficial to further explore the sustainability effects.6 There are even suggestions that different exercise programs (altering intensity and duration etc.) may be better suited, depending on the severity of depression.

One notable finding is that the impact of exercise on mental health has been suggested as being similar to that of cognitive behavioural therapy and emotion regulation. Exercise may improve an individual’s ability to tolerate negative effect or high levels of arousal, as during exercise individuals experience these sensations in a non-threatening context. This has potential to improve the ability to tolerate and cope with these sensations - similar to those experienced with anxiety and forms of psychological distress.8,9 A range of research therefore highlights how physical activity and exercise can positively influence mental health.

Room for improvement

Whilst reducing the risk of poor mental health among young adults and children is no simple task, evidence suggests there is room for progress from both a nutritional and physical activity/exercise perspective. A study by Zahra et al involved a sample of young adults aged 12-16 years.10 It found that young people who reported eating irregularly and consuming junk food daily were at a significantly greater risk of poorer mental health. The scale of the problem is indicated by National Diet and Nutrition Survey (NDNS) data from the UK, which highlights that mean consumption of fruit, vegetables and fibre intake was significantly below the recommendations, with as little as 4% of children aged 11-18 years meeting the guidelines for fibre intake.11

Initiatives to prevent sedentary behaviours and encourage more physical activity are also needed. A systematic review from Hoare et al reported cases of children using screens (TV, media entertainment, and computers) for leisure purposes – a generally sedentary activity.12 The findings showed strong consistent evidence for a relationship between depressive symptoms and psychological distress, with cases of participants using screens for leisure for >4 hours/day. Schools may also play a vital role in this, not just from a nutrition standpoint - with elements such as education on a healthier dietary intake and meal preparation - and with further encouragement/promotion of exercise throughout the curriculum, given the well-established physical and mental health benefits.13,14,15


It is clear that a healthy diet and physical activity/exercise can have a positive influence on adolescent mental health. The support and promotion of a healthy lifestyle can prevent symptoms associated with poor mental health - even facilitating physical and mental well-being later in life. Whilst these two factors are certainly not the only ones that can support significant improvements, they should be viewed as key elements of a holistic approach to improving adolescent mental health.

Harrison Prince December 2022



  1. Khalid, S., Williams, C, M. and Reynolds, S, A. (2017) ‘Is there an association between diet and depression in children and adolescents? A systematic review’, British Journal of Nutrition, 116, pp. 2097-2108. doi:10.1017/S0007114516004359
  2. Rossa-Roccor, V., Richardson, C, G., Murphy, R, A. and Gadermann, A, M. (2021) ‘The association between diet and mental health and wellbeing in young adults within a biopsychosocial framework’, PLOS ONE, 16 (6), pp. 1-19.
  3. Jacka, F, N., Kremer, P, J., Berk, M., Silva-Sanigorski, A, M., Moodie, M., Leslie, E, R., Pasco, J, A. and Swimburn, B, A. (2011) ‘A Prospective Study of Diet Quality and Mental Health in Adolescents’, PLOS ONE, 6 (9), pp. 1-7.
  4. O’Sullivan, T, A., Robinson, M., Kendall, G, E., Miller, M., Jacoby, P., Silburn, S, R. and Oddy W, H. (2008) ‘A good-quality breakfast is associated with better mental health in adolescence’, Public Health Nutrition, 12 (2), pp. 249-258.
  5. Ahm, S. and Fedewa, A, L. (2010) ‘A Meta-analysis of the Relationship Between Children’s Physical Activity and Mental Health’, Journal of Pediatric Psychology, 36 (4), pp. 385-397.
  6. Wang, X., Cai, Z,-D., Jiang, W-T., Fang, Y-Y., Sun,W-X. and Wang, X. (2022) ‘Systematic review and meta-analysis of the efects of exercise on depression in adolescents’, Child and Adolescent Psychiatry and Mental Health, 16 (16), pp. 1-19.
  7. Chekroud, S, R., G, R., Zheutlin, A, B., Paulus, M., Krumholz, H, M., Kystal, J, H. and Chekroud, A, M. (2018) ‘Association between physical exercise and mental health in 1·2 million individuals in the USA between 2011 and 2015: a cross-sectional study’, Lancet Psychiatry, 5 (9), pp. 739-746. S2215-0366(18)30227-X
  8. Smith, P, J. and Merwin, R, M. (2021) ‘The Role of Exercise in Management of Mental Health Disorders: An Integrative Review’, Annu Rev Med, 72, pp. 45-62. doi: 10.1146/annurev-med-060619-022943
  9. Stonerock, G, L., Hoffman, B, M., Smith, P, J. and Blumenthal, J, A. (2015) ‘Exercise as Treatment for Anxiety: Systematic Review and Analysis’, Annals of Behavioral Medicine, 49 (4), pp. 542-556.
  10. Zahra, J., Ford, T. and Jodrell, D. (2013) ‘Cross-sectional survey of daily junk food consumption, irregular eating, mental and physical health and parenting style of British secondary school children’, Child: care, health and development, 40 (4), pp. 481-491.
  11. NDNS (2020) National Diet and Nutrition Survey [online]. Available: <>
  12. Hoare, E., Milton, K., Foster, C. and Allender, S. (2016) ‘The associations between sedentary behaviour and mental health among adolescents: a systematic review’, International Journal of Behavioral Nutrition, 13 (108), pp. 1-22. doi 10.1186/s12966-016-0432-4
  13. Cooper, K, H., Greenberg, J, D., Castelli, D, M., Barton, M., Martin, S, B. and Morrow, J, R. (2016) ‘Implementing Policies to Enhance Physical Education and Physical Activity in Schools’, Research Quarterly for Exercise and Sport, 87 (2), pp. 133-140.
  14. Muzaffar, H., Metcalfe, J, J. and Fiese, B. (2018) ‘Narrative Review of Culinary Interventions with Children in Schools to Promote Healthy Eating: Directions for Future Research and Practice’, Current Developments in Nutrition, 2 (6), pp. 1-10.
  15. Parletta, N., Zarnowiechi, D., CHO, J., Wilson, A., Bogomolova, S., villani, A., Itsiopoulos, C., Niyonsenga, T., Bluden, S., Meyer, B, Segal, L., Baune, B, T. and Kerin, O’Dea. (2019) ‘A Mediterranean-style dietary intervention supplemented with fish oil improves diet quality and mental health in people with depression: A randomized controlled trial (HELFIMED)’, Nutritional Neuroscience, 22 (7), pp. 474-487.