Good mental health translates to good physical health – and the inverse is also true. Being physically well affects mental health. Research shows that proper nutrition and regular exercise play an enormous role in supporting mental well-being. It’s also harder to keep mentally well when you’re eating less-than-nutritious foods. Studies show that fast food (a convenient, easy choice for those struggling with their mental health) can lead to feelings of depression and higher levels of anxiety.

So how does diet actually impact your mood? Let’s travel to the gut and find out!

The Two-Way Connection of Nutrition and Mental Health

Mental illness is one of the most common conditions that affect people worldwide. According to research published in June 2022 by the World Health Organization (WHO), nearly a billion people around the globe suffer from some form of mental disorder. The figure gets even grimmer when you realize that it includes nearly one in seven teenagers worldwide.

The WHO also found that rates of depression and anxiety have skyrocketed 25% since the beginning of the COVID-19 pandemic. And according to WHO director-general Tedros Adhanom Ghebreyesus, “Good mental health translates to good physical health.... Investment into mental health is an investment into a better life and future for all.”

If you have a mental illness, struggle emotionally, or have mental health concerns – or know someone who does – there are ways to get help. Organizations like CheckPoint, HelpGuide, and the National Institute of Mental Health all offer resources to find help for you, a friend, or a family member.

The relationship between the food you eat and your gut

Have you ever been nauseated before important events? Do feelings of anxiety send you running to the restroom? The gastrointestinal (GI) system is highly sensitive to our emotions – there’s a reason it’s known as a “gut feeling.”

Your GI tract is home to trillions of bacteria that influence the production of neurotransmitters, which are chemical substances that work around the clock to carry messages from the gut to your brain (and then back to the gut – it's a feedback loop). A well-rounded diet promotes the growth of bacteria that improve neurotransmitter function, while a poor diet can lead to inflammation and slow down production of neurotransmitters. Two chemicals integral to good mental health – dopamine and serotonin – are part of this process as well. Serotonin, in particular, is mainly manufactured in the GI tract, which means that feeding your healthy gut bacteria leads to proper production of this feel-good hormone.

This connection between gut and brain has become clearer over the years, with research revealing that they are intricately linked. Poor gut health has even been reported as one possible cause for several mental disorders, including anxiety and depression. Stress can exacerbate digestive problems, and digestive upset contributes to stress levels. Managing mental health and gut health are nearly one and the same.

Six Foods to Boost Your Mental Health

Certain foods and food groups have the potential to improve your mental health, working as a complement to appropriate coaching, psychological counseling, and any medications your care team determines necessary.

Whole grains

Whole grains are digested more slowly than processed grains, reducing blood sugar spikes that can cause inflammation and, therefore, spikes in anxiety. The creator of the Anti-Inflammatory Diet and Food Pyramid, Andrew Weil, MD, recommends eating at least three to five servings of whole grains each day to improve inflammation levels. Whole grains include brown rice and wild rice, barley, steel-cut oats, and quinoa.

Fermented foods

Fermented foods are key to a healthy digestive system and gut, as they balance the ratio between good and bad bacteria. They have both probiotics and prebiotics, which are crucial for gut health. An Oxford University study shows that eating prebiotics – foods that feed probiotics to create a healthy gut – reduces cortisol (the stress hormone) response, improving emotional well-being. Fermented foods include kimchi, sauerkraut, pickles, kombucha, and kefir.

Leafy greens and cruciferous vegetables

Leafy greens, such as kale, spinach, collards, and Swiss chard, are high in folate, which helps your body manufacture the mood-regulating chemicals serotonin and dopamine. Higher levels of these “happy hormones” correlate to lower levels of cortisol in the bloodstream.

Cruciferous vegetables like broccoli, cauliflower, and cabbage contain high levels of fiber, a key component in supporting gut health. Researchers found that a diet including enough fiber “potentially lowers inflammation by modifying both the pH and the permeability of the gut.” Lower levels of inflammation can then alter neurotransmitter connections and reduce symptoms of depression.

Foods high in omega-3s

Research shows that rates of depression are lower in countries where the populations consume higher amounts of fish. It’s thought that the essential omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) – which help develop brain tissue – can prevent depression and anxiety. Foods high in omega-3 fatty acids include salmon and cod, chia seeds, walnuts, and flaxseed.

Garlic and onions

Members of the allium family, garlic and onions are rich in prebiotics, delivering fiber and nutrition to your gut microbiome. Allium flavanols have anti-inflammatory effects and can prevent oxidative stress that’s been linked to depression and anxiety.

Foods high in vitamin D

Rates of depression are higher in people who have a vitamin D deficiency. It’s also thought to play a role in seasonal affective disorder, or SAD – depression that commonly starts in the fall, lasts through winter, and subsides in the sunnier spring and summer months. Our bodies produce vitamin D after sun exposure, but too much sun exposure can lead to an increased risk of developing skin cancer. Foods high in vitamin D include eggs, mackerel, mushrooms, and vitamin D–fortified milk.

The Bottom Line

The principles of nutritional psychology tell us that psychiatry and nutrition are tied. Psychologist and IIN visiting faculty member Drew Ramsey, MD, emphasizes this connection and recommends focusing on nutrient-dense food as a way to find balance when dealing with food and mental health.

But nutrition is just one part of ensuring mental well-being. Protecting your mental health also involves learning coping skills, allowing yourself to say no when the situation calls for it, practicing meditation and grounding techniques, drinking enough water, and seeking help from professionals when you need to.

IIN takes an integrative and holistic approach to wellness, embracing and teaching the concept of integrative nutrition. Integrating all aspects of well-being – from adequate nutrition to fostering positive relationships to having a fulfilling career – helps to create a well-rounded, satisfying life.