The Relationship Between Nutrition and Mental Health

By Dr. Matthew Loux and Derek Loux  |  04/07/2025

The influence of diet choices on people’s mental well-being has become a thriving field of interest in the scientific community. The potential relationship between our diet and psychological health is becoming relevant as there is more awareness about mental health conditions. Certainly, our physical health, our emotions and thinking are all impacted by nutrition.  

The Importance of Healthy Foods

Recent studies have found a strong connection between the brain and the gut microbiome. This connection is due to the neurons the gut microbiome houses as well as its capability to synthesize different neurotransmitters.

A healthy diet of more fruits, leafy green vegetables, fish, and legumes is correlated with a better mental state. Refined, processed food has been linked to depression symptoms.

The size of the hippocampus (the part of the brain that impacts learning and memory) is negatively affected by eating diets high in refined carbohydrates and trans fats.

Studying Nutrition and Mental Health

Nutritional psychiatry is an emerging field that studies how our dietary choices affect our emotional state. Professionals in this field are studying how certain nutrients and dietary changes might help people to manage some mental health issues.

For instance, random controlled trials indicate that diet may influence the emergence of mood disorders and depression. These findings suggest that dietary changes can positively impact traditional mental health treatment while paving the way for prevention and intervention.

By understanding the intricate relationship between nutrition and mental wellbeing, nutritional psychiatry experts will be able to analyze diets, water consumption, and overall nutrition. With this information, they can help people assess their lifestyles and diets accordingly and create guidelines to follow.

This guidance can support individuals in taking proactive measures to enhance their mental health. Dietary interventions may include educating people about changes such as reducing unhealthy eating habits.

The Connection Between the Brain and Gut Microbiome

Researchers are studying the effects of probiotics (beneficial live bacteria) and prebiotics (compounds that aid in the growth of probiotics) on mental health. In one study in the journal Microorganisms, researchers found that people who used probiotics reported lower stress and anxiety.

Similarly, evidence suggests that probiotics enhance the growth of beneficial bacteria in the gut and improve symptoms of depression, according to a study published in the medical journal Cureus.

The link between inflammation, the gut, and mental disorders is one of the more prominent focuses of research. When gut inflammation is chronic, it can cause ‘leaky gut,’ which is the thinning of the intestinal wall. This condition causes harmful substances to enter the bloodstream, increasing inflammation throughout the body and damaging the brain.

The Role of Diet in Depression

Depression remains one of the most common mental disorders. The number of depression cases has intensified recently, which poses an emerging public health problem.

Insufficient nutrients like protein, B vitamins, vitamin D, magnesium, zinc, selenium, iron, calcium, and Omega-3 highly influence the brain and the nervous system and can lead to depressive symptoms. In addition to traditional treatments of depression, nutritional interventions could include encouraging healthy eating and taking dietary supplements.

However, altering a daily diet is not the sole aspect of reducing the risk of depression. Physical exercise, sleep, stress management, and social support are beneficial for emotional well-being.

Important Energy Sources for Good Brain Health

Eating more of the right vitamins and minerals can improve both our physical health and our physiological health. When it comes to overall health as well as better mental health, some important aspects of your diet include getting enough foods that contain these nutrients:

• Omega-3
• B vitamins
• Vitamin D
• Magnesium
• Amino acids
• Antioxidants

Omega-3

People who experience depression generally have poor cognitive function, but research shows that increasing Omega-3 intake greatly improves cognitive function and reduces the risk of depression,

Walnuts and flax seeds are excellent vegetarian sources of Omega-3. Incorporating these foods into simple meals such as salads and oatmeal can greatly help reduce inflammation in the body over time.

B Vitamins

A low level of any B vitamin will result in depression and negative impacts on self-esteem and cognitive function. B vitamins help convert food and drink into energy to support the body’s brain and metabolism.

Folate, B6, and B12 work together to maintain the body’s energy supply and production. B6 supports cognitive functions by enabling the synthesis of serotonin and dopamine. Legumes such as beans, broccoli, and fortified cereals are good sources of B vitamins.

Vitamin D

An important benefit of vitamin D stems from its proven positive effect on psychological health. A multitude of studies have demonstrated a link between depression and low vitamin D. Getting direct exposure to sunlight and eating dairy products and fatty fish can boost vitamin D blood levels.

Magnesium

Another vital element of healthy eating includes getting enough magnesium; it calms the nervous system and is considered to be soothing. It aids in controlling the functioning of neurotransmitters – the chemical messengers of our nervous system.

Magnesium may also reduce the effects of stress or anxiety. This nutrient is found in nuts, seeds, whole grains, and green vegetables.

Amino Acids

Amino acids are important for the production of neurotransmitters. For instance, the amino acid tryptophan produces serotonin, which is a neurotransmitter that has mood-regulating functions. Some potential mental health problems associated with low serotonin can include:

• Depression
• Anxiety
• Obsessive-compulsive disorder
• Post-traumatic stress disorder (PTSD)
• Schizophrenia
• Panic disorders

Foods like turkey, eggs, and dairy products contain tryptophan and can help promote positive mental health.

Antioxidants

Antioxidants protect the body’s cells from damage. Some research shows that antioxidant supplements may improve depression symptoms. Antioxidants are also found in foods like olive oil, nuts, and beans.

Diet and Mental Health

Poor diets, such as diets that are high in sugar, can lead to blood sugar spikes and crashes. These rapid fluctuations can result in emotional instability and even insulin resistance.

Such metabolic dysfunction increases the risk of mood disorders. People who eat excess processed foods have higher rates of anxiety and depression.

The Mediterranean diet is related to better nutrition-related mental health outcomes than the Western diet. Experts believe that the Mediterranean diet’s anti-inflammatory properties and high levels of antioxidants enhance its positive effects on mental well-being. Chronic inflammation resulting from unhealthy diet choices can lead to the disruption of normal brain function, leading to depression and anxiety.

In addition, inflammation and nutritional imbalances exacerbate many medical conditions such as diabetes. Cutting down on processed foods and sugars may improve these conditions and alleviate various mental health conditions.

Hydration and Its Impact on Cognitive and Emotional Well-Being

Hydration is very important for cognitive and emotional functioning. Neurotransmitters need water to carry signals to and from the brain. Proper hydration helps these neurotransmitters to work properly and aids in mood and cognitive performance.

Water deficits result in reduced attention span, short-term memory loss, and reaction time. Mild dehydration leads to mood changes, anger, and an increase in anxiety and tiredness.

The imbalance caused by dehydration causes an increased risk of anxiety, depression, and other negative emotions. Some signs of dehydration may include:

• Headaches
• Dizziness
• Fatigue
• Confusion and an inability to focus

Hydration, however, reduces the risk of these symptoms.

Special Diets and Their Effects on Mental Health

There are several special diets that have had an influence on people’s physical and mental health. These diets include:

• The keto diet
• The Mediterranean diet
• The vegan or vegetarian diet
• The gluten-free diet

Keto Diet

The keto (ketogenic) diet involves consumption of low carbohydrates and higher amounts of fats that shift your metabolism from glycolysis to fatty acid oxidation. This diet is thought to result in improved emotional well-being, according to a study conducted by researchers at Northumbria University. Subjects on the keto diet reported being calmer and alert with reduced stress and anxiety.

Mediterranean Diet

Researchers have conducted extensive studies of the mental health impacts of the Mediterranean diet. This diet is based largely on eating fruits, vegetables, whole grains, lean meat, and healthy fats. It is high in antioxidants, anti-inflammatory, and nutrient-dense foods that increase cognitive ability and decrease the chances of depression.

Recent studies have noted an increase in the potential positive impacts of ketogenic and low-carb diets on brain activity and mood regulation. These diets increase production of ketones, which are used as an alternative energy source by the brain. This energy source may decrease feelings of anxiety and depression.

Vegan and Vegetarian Diets

Vegan and vegetarian diets, if properly planned, can also promote mental health. For anyone choosing a vegan or vegetarian diet, it is imperative to monitor the level of vitamin B12, iron, and Omega-3 fatty acids.

These nutrients are predominantly found in animal products. A deficiency in these nutrients can cause symptoms of depression and cognitive decline.

Tempeh and fortified foods such as plant-based milks are good sources of vitamin B12. Eating legumes, dark leafy green vegetables, and beans help vegetarians and vegans get proper amounts of iron in their diet. Similarly, eating flaxseeds, chia seeds, walnuts, and edamame can help vegans and vegetarians get necessary Omega-3 fatty acids.

Gluten-Free Diet

Gluten-free and elimination diets have been studied for their potential to improve conditions like anxiety and depression. People suffering from celiac disease or gluten sensitivity show marked improvement in mood and cognitive functioning when gluten is removed from their diet. Elimination diets that specifically identify and eliminate certain food allergens may reduce inflammation, improving mental health.

Practical Tips for Improving Your Diet and Mental Health

First and foremost, it is essential consult a physician before making changes to your diet. If you’re interested in eating healthy foods, consider these steps:

• Eat a diet that consists of various fruits, vegetables, whole grains, lean meats and healthy fats. These foods contain vitamins, minerals and antioxidants that are crucial to brain function and mood control.

• Plan meals in advance to create a balanced meal. Balanced meals help people to maintain a healthy intake of essential nutrients.

• Avoid consuming sugars and processed foods whenever possible. Excess sugar can worsen blood sugar levels, which negatively influences a person's overall energy and mood. Consider substituting natural sugars from fruits as well as unprocessed food.

The relationship between nutrition and mental health is still an emerging area of research, but it is clear that nutrition can have consequences for one’s well-being. With nutrition, we can make decisions in mental health by learning how certain nutrients and dietary patterns impact emotional well-being.

Intentionally making systematic and strategic changes, however small, to create a healthy diet, can affect mental well-being. Shifting the focus to nutrition may greatly enhance one's mood, cognitive function, and overall life quality.

Public Health Degrees at American Military University

For adult learners interested in mental health, public health, and other related topics, American Military University (AMU) offers several public health degrees:

• An online Associate of Science in Public Health
• An online Bachelor of Science in Public Health
• An online Master of Public Health (MPH)

Courses in these programs include topics such as public health in America, foundations of nutrition, health services organization, and an introduction to healthcare administration. Other courses include ethical issues in public health, health policy, and epidemiology.

All of AMU’s courses are taught by expert faculty members with intensive knowledge of public health. In addition, the Master of Public Health has received specialty accreditation from the Council on Education for Public Health (CEPH®).

CEPH is a registered trademark of the Council on Education for Public Health.