“Let food be thy medicine, and let medicine be thy food.”
- Hippocrates
For many years, mental health and nutrition were treated as completely separate areas of health. We often thought about mental health purely through the lens of psychology, counselling, medication, or life experiences.
However, research over the last decade has begun to dramatically change this picture.
Scientists are now exploring how the food we eat may influence mood, anxiety, stress resilience, concentration, energy, and even serious mental health conditions. This emerging area of research is often referred to as nutritional psychiatry.
While nutrition is not a replacement for appropriate medical or psychological care, there is growing evidence that food can play an important supporting role in mental well-being.
The Brain is Metabolically Demanding
Although the brain only makes up around 2% of body weight, it uses around 20% of the body’s energy.
To function well, the brain relies on a steady supply of nutrients, including:
- Protein and amino acids
- Essential fats such as omega-3
- B vitamins
- Iron
- Zinc
- Magnesium
- Stable blood sugar levels
The brain also communicates constantly with the gut through the gut-brain axis. Gut bacteria help produce neurotransmitters and influence inflammation, immune function, and even stress responses.
Research now suggests that inflammation, blood sugar instability, poor gut health, nutrient deficiencies, and metabolic dysfunction may all influence mental well-being in some individuals.
Food Patterns Matter More Than Individual ‘Superfoods’
No single food can cure anxiety or depression. However, overall dietary patterns appear to matter significantly.
Research consistently suggests that diets rich in:
- Vegetables
- Fruit
- Nuts and seeds
- Oily fish
- Olive oil
- Beans and legumes
- Quality protein
- Fibre-rich foods
are associated with better mental health and well-being.
In contrast, diets high in ultra-processed foods, refined carbohydrates, sugar, and highly processed fats are associated with poorer mental health outcomes and increased systemic inflammation.
This does not mean people should strive for perfection or feel guilty about food choices. Mental health is complex and influenced by many factors, including trauma, stress, sleep, hormones, finances, relationships, and genetics.
However, nutrition may be one important piece of the puzzle.
Blood Sugar and Mood
One area I frequently help clients with is balancing their blood sugar.
Rapid spikes and crashes in blood sugar can affect:
- Energy levels and fatigue
- Irritability
- Concentration
- Anxiety symptoms
- Cravings
- Sleep
- Stress resilience
Many people notice they feel calmer and more emotionally stable when meals include:
- Protein
- Healthy fats
- Fibre
- More stable carbohydrates
rather than relying on sugary snacks or refined foods.
This does not mean people need to eliminate carbohydrates completely, but balancing meals can make a significant difference to energy and mood regulation.
The Gut-Brain Connection
The gut and brain are deeply connected.
Around 90% of serotonin is produced in the gut, and gut bacteria constantly communicate with the nervous system.
Emerging research suggests that gut health may influence:
- Anxiety
- Low mood
- Stress resilience
- Cognitive function
- Inflammation
- Sleep
This is one reason why my approach is not just focusing on nutrients, but also on supporting gut health.
Ketogenic Diets and Mental Health: A New Area of Research
One of the most interesting and rapidly developing areas of nutritional psychiatry is the use of ketogenic diets in mental health conditions.
A ketogenic diet is a very low-carbohydrate, moderate-protein, high-fat diet that changes how the body produces energy. Instead of relying mainly on glucose, the body begins producing ketones as an alternative fuel source.
Traditionally, ketogenic diets were used in epilepsy treatment. However, researchers are now exploring whether ketosis may also influence brain energy metabolism, inflammation, neurotransmitters, and mental health symptoms.
Recent research has investigated ketogenic diets in conditions including:
- Bipolar disorder
- Schizophrenia
- Severe depression
- Treatment-resistant mental illness
A 2026 study funded by the NIHR Oxford Health Biomedical Research Centre found that a ketogenic diet may help some individuals with treatment-resistant depression.
This is still an emerging field, and more research is needed. Importantly, ketogenic diets are not appropriate for everyone and should ideally be supervised by a qualified healthcare professional, particularly in people with medical conditions, eating disorders, or those taking medication.
However, these findings are helping researchers rethink the relationship between metabolism, brain function, and mental health.
Nutrition is Not About Blame
It is incredibly important to say this clearly:
Mental health conditions are not caused simply by ‘eating badly.’
People struggling with anxiety, depression, trauma, burnout, or chronic stress are not failing if nutrition feels difficult.
In fact, mental health challenges often make shopping, cooking, meal planning, and eating regularly much harder.
Nutrition should never be used to shame people.
Instead, food can be viewed as one tool that may help improve resilience, energy, and overall well-being alongside counselling, therapy, medication, community support, movement, sleep, and medical care where needed.
Small Changes Can Matter
Nutrition does not need to be extreme to make a difference.
Simple changes can often help support both physical and mental well-being:
- Eating regular meals
- Including protein with meals
- Increasing vegetables and fibre
- Reducing ultra-processed foods
- Supporting sleep
- Staying hydrated
- Increasing omega-3 intake
- Supporting gut health
Mental health is complex, but the growing field of nutritional psychiatry is reminding us that the way we nourish ourselves matters.
As research continues to advance, we may increasingly see nutrition become part of a more integrated, holistic approach to mental health care.
References & Further Reading
- Nutritional psychiatry: Towards improving mental health by what you eat.
- British Nutrition Foundation: Food and the Brain
- Mind UK: Food and Mental Health
- The Potential Role of the Ketogenic Diet in Serious Mental Illness
- NIHR Oxford Health Biomedical Research Centre (2026): Ketogenic diet and severe depression research
