From the Guidelines
Adequate caloric intake, tailored to an individual's needs, is crucial for improving mental health, with a balanced diet of 1,800-2,500 calories daily recommended, including complex carbohydrates, lean proteins, healthy fats, and plenty of fruits and vegetables. This approach is supported by the most recent and highest quality study, which emphasizes the importance of nutritional interventions in managing mental health symptoms, such as anxiety and depression 1. The study highlights the need for well-defined dietary interventions and adequate monitoring of nutritional compliance to assess the duration of effects on mental health outcomes.
When considering the relationship between caloric intake and mental health improvement, it is essential to prioritize a balanced diet that includes:
- Complex carbohydrates
- Lean proteins
- Healthy fats
- Fruits and vegetables
- Foods rich in omega-3 fatty acids, B vitamins, and antioxidants, which can particularly benefit brain health
Both undereating and overeating can negatively impact mental health, with insufficient calories leading to nutrient deficiencies that affect neurotransmitter production, and excessive calorie consumption contributing to inflammation and metabolic issues that worsen mood disorders. For individuals with specific mental health conditions, consulting with a healthcare provider to tailor their diet is recommended, as some medications may affect appetite or metabolism 1.
The importance of combining proper nutrition with regular physical activity, adequate sleep, and appropriate mental health treatments cannot be overstated, as this comprehensive approach provides the most effective way to manage mental illness. While nutrition is a critical component, it should complement rather than replace conventional mental health treatments like therapy and medication when needed. As noted in the guidelines for weight maintenance and reduction, matching intake of total energy to overall energy needs and achieving a level of physical activity that matches or exceeds energy intake is essential for overall health and well-being 1.
From the Research
Relationship Between Caloric Intake and Mental Health Disorders
- The relationship between caloric intake and mental health disorders is complex, and research suggests that a healthy diet may play a crucial role in reducing the risk of developing mental health disorders 2, 3, 4, 5.
- A study published in 2016 found that a combination of healthy dietary practices, including following traditional dietary patterns, increasing consumption of fruits and vegetables, and limiting intake of processed foods, may reduce the risk of developing depression 2.
- Another study published in 2020 found that omega-3 fatty acids, which are commonly found in fatty fish, nuts, and seeds, may have a positive effect on anxiety symptoms 6.
- A systematic review of observational studies published in 2020 found that high total intake of fruits and vegetables, as well as some specific subgroups such as berries, citrus, and green leafy vegetables, may promote higher levels of optimism and self-efficacy, and reduce the level of psychological distress and depressive symptoms 4.
- A review of the evidence published in 2021 found that dietary fibre, omega-3 fatty acids, and other nutraceuticals may have a positive effect on mental health outcomes, and that special diets such as the ketogenic diet and food sensitivities may be relevant in the management of severe mental illness 5.
Key Dietary Recommendations
- Follow traditional dietary patterns, such as the Mediterranean, Norwegian, or Japanese diet 2.
- Increase consumption of fruits, vegetables, legumes, whole-grain cereals, nuts, and seeds 2, 4.
- Consume higher amounts of foods rich in omega-3 fatty acids, such as fatty fish, nuts, and seeds 2, 6.
- Limit intake of processed foods, fast foods, commercial baked goods, and sweets 2.
- Be mindful of probiotic gut bacteria and consider increasing consumption of fermented foods such as yogurt and kefir 2.
Mechanisms Underlying the Relationship Between Diet and Mental Health
- The gut-brain axis, which refers to the bidirectional communication network between the gut microbiome and the central nervous system, may play a key role in the relationship between diet and mental health 5.
- Inflammatory response, brain-derived neurotrophic factor (BDNF), cortisol, and cardiovascular activity may also be involved in the relationship between omega-3 fatty acids and anxiety reduction 6.
- Dietary fibre may have a dose-dependent relationship with risk of depression, and may be an important component of a healthy diet for mental health outcomes 5.