Diet, exercise, and mental disorders – public health challenges of the future

Abstract

A role of socio-medical causation, comprising social, environmental and lifestyle factors, in the etiology and prevention of diseases was proposed by the German public health pioneer Rudolf Virchow. In China, Sun Yat-sen regarded sanitation and health as indices of a country's prosperity and social civilization. Today, diet and physical activity are increasingly recognized as potentially modifiable lifestyle factors influencing the onset and outcomes of mental disorders. The life expectancy of many groups of people with mental illness is markedly reduced compared to the general population. This mortality gap is due partly to high rates of obesity and low rates of exercise. The present short review evaluates the evidence of the role of diet and exercise in the prevention and treatment of mental disorders. Associated public mental health issues are also discussed.

The effects of single nutrients in the treatment of mental disorders appear to be modest at best, while the investigation of dietary patterns seems more promising. Clinical studies using sound methodology are largely lacking, and rigorous trials assessing long-term outcomes of dietary approaches should be conducted. The associations between dietary patterns, adiposity, inflammation and mental health are a potentially valuable field of research. Epidemiological studies have shown that physical activity and exercise can prevent or delay the onset of various mental disorders and may have therapeutic benefits when used as sole or adjunct therapy in psychiatry. While findings of controlled studies are sparse, preliminary evidence suggests that physical activity can improve physical, subjective, and disorder-specific clinical outcomes.

Mental health is vital to public health. It is protective against unhealthy lifestyles, physical disease, and social inequalities. Emerging evidence demonstrates the effectiveness of lifestyle changes in the promotion of mental health and in the primary and secondary prevention of mental illness. The promotion of an active lifestyle and physical exercise is likely to be a highly cost-effective intervention in improving population mental health and wellbeing. Physical exercise appears to be a promising alternative or additional treatment option for individuals with mental disorders. The initiating and financing of high-quality studies examining the effects of physical exercise on mental disorders should be undertaken; such measures would have additional health benefits, such as positive cardiovascular and metabolic effects. Financial returns from large-scale investigations into exercise as a treatment for mental disorders cannot be expected. Support through public funding and non-profit organizations is needed in order to help counter the challenges posed by public mental health. Public health efforts may also include school-based interventions and the creation of environments conducive to physical activity and improved nutrition. Political interventions may be necessary.

In conclusion, public health should prioritize dietary factors and exercise in the combatting of mental disorders. The effectiveness of lifestyle changes involving diet and exercise in improving mental health should be evaluated in the treatment of individuals and in population-based public health programs.