Food and Behaviour Research

Donate Log In

Food and mood: how do diet and nutrition affect mental wellbeing?

Firth J, Gangwisch J, Borisini A, Wooton R, Mayer E (2020) BMJ 2020; 369 doi: 10.1136/bmj.m2382 

Web URL: Read this and related articles on NCBI


Poor nutrition may be a causal factor in the experience of low mood, and improving diet may help to protect not only the physical health but also the mental health of the population, say Joseph Firth and colleagues

Key messages

  • Healthy eating patterns, such as the Mediterranean diet, are associated with better mental health than “unhealthy” eating patterns, such as the Western diet
  • The effects of certain foods or dietary patterns on glycaemia, immune activation, and the gut microbiome may play a role in the relationships between food and mood
  • More research is needed to understand the mechanisms that link food and mental wellbeing and determine how and when nutrition can be used to improve mental health
Depression and anxiety are the most common mental health conditions worldwide, making them a leading cause of disability. Even beyond diagnosed conditions, subclinical symptoms of depression and anxiety affect the wellbeing and functioning of a large proportion of the population. Therefore, new approaches to managing both clinically diagnosed and subclinical depression and anxiety are needed.

In recent years, the relationships between nutrition and mental health have gained considerable interest. Indeed, epidemiological research has observed that adherence to healthy or Mediterranean dietary patterns—high consumption of fruits, vegetables, nuts, and legumes; moderate consumption of poultry, eggs, and dairy products; and only occasional consumption of red meat—is associated with a reduced risk of depression. However, the nature of these relations is complicated by the clear potential for reverse causality between diet and mental health. For example, alterations in food choices or preferences in response to our temporary psychological state—such as “comfort foods” in times of low mood, or changes in appetite from stress—are common human experiences. In addition, relationships between nutrition and longstanding mental illness are compounded by barriers to maintaining a healthy diet. These barriers disproportionality affect people with mental illness and include the financial and environmental determinants of health, and even the appetite inducing effects of psychiatric medications.

While acknowledging the complex, multidirectional nature of the relationships between diet and mental health, in this article we focus on the ways in which certain foods and dietary patterns could affect mental health.