From the Guidelines
A Mediterranean diet rich in vegetables, fruit, legumes, wholegrains, nuts, seeds, and olive oil has been shown to significantly improve symptoms of depression and anxiety. This traditional diet, which is low in red meat, has been the most studied dietary pattern globally and has demonstrated the potential to alleviate symptoms of depression, with 32% of individuals with major depressive disorder achieving remission in the landmark SMILES trial 1. The mechanisms underlying the effect of the Mediterranean diet on the brain are unclear but are likely to at least partially involve the microbiome.
Key components of the Mediterranean diet that may contribute to its beneficial effects on mental health include:
- High intake of fruits, vegetables, and whole grains, which provide essential nutrients for neurotransmitter production and reduce inflammation
- High intake of nuts, seeds, and olive oil, which are rich in healthy fats and antioxidants
- Low intake of red meat, which may reduce inflammation and improve gut health
It is essential to note that while the Mediterranean diet has been shown to improve symptoms of depression and anxiety, it may not be suitable for individuals with moderate or severe gastrointestinal symptoms, such as those with irritable bowel syndrome (IBS) 1. In such cases, a gentle Mediterranean diet that incorporates legumes low in FODMAPs and small amounts of vegetables high in FODMAPs may be more appropriate.
Overall, incorporating a Mediterranean-style diet into one's lifestyle, in conjunction with regular therapy and medication when needed, can have a synergistic effect on improving mental health outcomes, by providing essential nutrients, reducing inflammation, and supporting the gut microbiome, which influences brain function through the vagus nerve and immune system pathways 1.
From the Research
Relationship Between Diet and Mental Health Disorders
The relationship between diet and mental health disorders is complex, with various studies suggesting a link between certain nutrients and improved mental health outcomes.
- Omega-3 fatty acids have been shown to have a positive effect on anxiety and depression, with studies suggesting that they may reduce symptoms of these conditions 2, 3, 4, 5.
- The mechanisms by which omega-3 fatty acids exert their effects on mental health are not fully understood, but may involve reduction of inflammation, modulation of neurotransmitter function, and promotion of neuroplasticity 2, 3.
- Fruit and vegetable intake has also been linked to improved mental health, with high consumption of these foods associated with reduced symptoms of depression and anxiety 6.
- Specific types of fruit and vegetables, such as berries, citrus fruits, and green leafy vegetables, may have particularly beneficial effects on mental health 6.
- While the evidence suggests a positive relationship between diet and mental health, more research is needed to fully understand the mechanisms by which diet influences mental health outcomes and to establish standardized guidelines for the use of dietary interventions in the treatment of mental health disorders 2, 3, 4, 5.
Key Findings
- Omega-3 fatty acid supplementation may have a small to modest benefit for depressive symptomology, but the evidence is limited and heterogeneous 4.
- Fruit and vegetable intake is associated with improved mental health outcomes, including reduced symptoms of depression and anxiety 6.
- The relationship between diet and mental health is complex and influenced by a range of factors, including the type and amount of nutrients consumed, individual differences in nutritional status and health status, and the presence of other health conditions 2, 3, 4, 5.
Implications for Mental Health Treatment
- Dietary interventions, including omega-3 fatty acid supplementation and increased fruit and vegetable intake, may be a useful adjunct to traditional treatments for mental health disorders 2, 3, 4, 5.
- Further research is needed to establish the efficacy and safety of dietary interventions for mental health disorders and to develop standardized guidelines for their use 2, 3, 4, 5.