In addition to its unique ability to communicate with the brain, the gut is filled with bacteria responsible for the production of several neurochemicals, including about 95% of the body’s supply of serotonin, used by the brain to regulate both physiological and mental processes.

Numerous studies have shown that the gut-brain axis is a two-way street. Just as the gut affects the brain, the brain can also exert profound influences on the gut microbiome. Perhaps the most well-documented of these findings suggests psychological stress can suppress beneficial bacteria throughout the gut.

Although a future in which analyzing patient gut bacteria to treat mood disorders is still likely far away, practical applications of these gut-brain findings are emerging. From airplanes to restaurants, mood-boosting menus aim to improve patrons’ wellbeing, support fliers’ immune systems and mitigate passenger jetlag. While those goals may seem lofty, research has indicated that certain dietary changes do indeed have psychopharmacologic effects, including:

Adding vitamins and essential fatty acids

In Nutritional Psychiatry, additions of dietary vitamins and essential fatty acids are the best studied interventions. Due to their modulation of neurotransmitters and their anti-inflammatory effects, omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been the focus of many of these dietary supplementation studies. One placebo-controlled meta-analysis of EPA and DHA supplementation in the treatment of mood disorders found a significant effect with EPA being more effective than DHA. While supplementation of folic acid, vitamin E and vitamin D have also been investigated, the results have been mixed.

Removing substances

Some clinicians and researchers use elimination diets in children diagnosed with attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASD). For ADHD, the elimination of dietary artificial food colors has been shown to have significant effects in children with food sensitivities. While gluten and/or casein are often eliminated for ASD, there has been little to no evidence documenting the efficacy of this dietary change.

Adopting the Mediterranean diet

The Mediterranean diet is characterized by a high intake of anti-inflammatory foods including vegetables, legumes, fruits and nuts, unrefined grains and unsaturated fats. One randomized-control trial, which assigned patients with severe depression to either 7 counseling sessions to adopt the Mediterranean diet or 7 social support sessions, found a significantly higher remission rate in the diet group: 32% vs. 8%. Another study found that adherence to the Mediterranean diet may also help prevent a series of other brain diseases including cognitive impairment.

Supporting the gut microbiome

There is increasing evidence that, in addition to their role in metabolism, gut bacteria may have significant effects on the brain. Diet plays an important role in shaping the microbiome, with evidence showing that dietary changes can induce large microbial shifts within 24 hours. While the probiotic market has grown rapidly, regulation of supplements is limited as is the clinical evidence of their efficacy.

Fasting and/or adopting the ketogenic diet

The ketogenic diet is characterized by a high fat and low carbohydrate intake. For children with treatment-refractory epilepsy, fasting and adopting the ketogenic diet have been found to have over a 50% response. While controlled trials are needed, preliminary case studies suggest these dietary changes may be effective in the treatment of psychiatric disorders.

If you’d like to learn about other nutritional interventions for those with mental health conditions, or to make a referral, please call 1-877-847-3984 or contact us here.