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Nutritional Therapy in the Treatment of Mental Disorders

By Susan A. Knight

It’s well understood that psychosocial, medical, and developmental factors contribute to mental health disorders. While psychotherapy paired with medication is widely viewed as the most effective way to promote recovery, nutritional therapy has garnered interest for its potential to support treatment and recovery efforts.

Nutritional therapy is part of the broader field of nutritional psychology that looks at how nutrients affect mood and behavior. As a growing body of scientific evidence provides greater insight into the relationship between various nutrients and the body’s biochemical functions, nutrition is increasingly being viewed as a relevant factor in mental health. The evidence suggests that targeted nutrient intake, in the form of food or dietary supplements, may help to improve the efficacy of conventional treatment approaches.

Alleviating Symptoms With Dietary Supplements
Vitamins and minerals are referred to as micronutrients. They don’t provide energy to the body in the way that macronutrients (i.e., carbohydrates, proteins, and fats) do. However, micronutrients are an essential part of nutrition, supporting a wide variety of metabolic and biochemical processes within the body. Micronutrient deficiencies have long been known to contribute to illness and disease—so much so that historically, vitamins were discovered primarily through the deficiency diseases that would arise when the vitamin was absent in the diet.

Studies have shown that in the United States and other developed countries, essential vitamins and minerals are often deficient across the general population. For patients experiencing mental disorders, these deficiencies tend to be even more pronounced. In many cases, the relationship between specific micronutrients and specific disorders isn’t fully understood. But the research to date indicates that dietary supplements that provide these essential nutrients can help to alleviate some of the symptoms associated with common mental health disorders such as major depression, bipolar disorder, and schizophrenia.

Major depression: The results of several case studies have shown that magnesium can help to support recovery in patients with depression (Lakhan & Vieira, 2008). Supplementation with certain B vitamins has also been linked to a decrease in depression symptoms and improvements in mood and mental health (Lewis et al., 2013).

Bipolar disorder: According to Lakhan and Vieira, it’s possible that the trace mineral vanadium may be a causal factor in this disorder. They report that vitamin C has been shown to protect the body from the damage caused by excess vanadium. As a result, supplementation with vitamin C may be useful as part of treatment, particularly for decreasing manic symptoms. They further report that supplementation with certain B vitamins may also help to support treatment of this disorder, noting that 80% of individuals with bipolar disorder have some vitamin B deficiencies.

Schizophrenia: In a study to investigate the utility of nutritional approaches as an adjunct to antipsychotic medication in the treatment of schizophrenia, Arroll, Wilder, and Neil (2014) describe the noteworthy findings related to vitamin B9, also known as folate. They report that in studies measuring folate levels, patients with schizophrenia have consistently been found to have significantly lower levels of this essential vitamin in comparison with control participants. They note that this isn’t necessarily due to dietary intake; these low folate levels may be somehow tied to genes linked to folate metabolism. In this case, folate supplementation as an adjunct to antipsychotic therapy may be of benefit to those with a genetic susceptibility.

Omega-3 Fatty Acids as a Therapeutic Tool
There are several different types of omega-3 fatty acids, but two of the more important ones are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These are both found primarily in fish, and they are both needed to support healthy bodily functions.

Lakhan and Vieira state that deficiency in omega-3 fatty acids is one of the most common nutritional deficiencies seen in patients with mental disorders. Noting that population studies have linked high fish consumption to a low incidence of mental disorder, they assert that the reduced incidence of mental disorders where there is higher fish consumption is directly linked to the increased intake of omega-3 fatty acids.

An Italian study evaluated research data from 1980­–2015 to assess the efficacy of omega-3 fatty acids in the treatment of various mental health disorders including schizophrenia, bipolar mood disorders, anxiety disorders, and obsessive-compulsive disorder (Bozzatello, Brignolo, De Grandi, & Bellino, 2016). The study notes that in patients with schizophrenia, postmortem brain cell samples often show low levels of EPA and DHA. The researchers go on to state that in individuals with schizophrenia or related psychotic disorders, certain omega-3 fatty acid levels are reduced compared with healthy control samples. These findings don’t offer anything concrete as far as potential treatment options. However, they do indicate the need for more research to determine whether supplementing with omega-3 fatty acids may have a beneficial effect in the treatment of psychotic disorders.

The findings from the aforementioned Italian study related to depression were also inconclusive. On one hand, the researchers note the confirmed beneficial effect of omega-3 fatty acid supplementation on depressive symptoms in elder (aged 66–95 years) women residents in a nursing home. But at the same time, they go on to state that there is no widespread consensus concerning the efficacy of omega-3s in the treatment of depression.

Ultimately, the researchers summarize by stating that omega-3 fatty acids show promise as a therapeutic tool in the treatment of psychiatric illnesses, but they caution that the findings from studies and reviews are too divergent to draw any firm conclusions (Bozzatello et al, 2016).

Clinician Receptiveness to the Use of Supplements
Regarding clinician receptiveness to the use of supplements in treatment plans, Lakhan and Vieira describe clinicians as showing “tremendous resistance” to the use of supplements as part of treatment, mostly due to their lack of knowledge on the subject. They go on to state that while it will take some time for clinicians to become educated on all the nutritional and supplemental options available, doing so is an important task that shouldn’t be ignored.

If indeed there was such a level of resistance as the researchers describe, clearly much has changed over the past decade. Assessing the landscape today, clinicians are now eager and receptive to being educated on the ways in which nutritional therapies may be able to support patient treatment plans. In response to this interest, a growing number of relevant training programs targeting social workers, psychologists, therapists, and other behavioral health care specialists are becoming available.

For instance, John F. Kennedy University in California offers an online certificate program in nutritional psychology especially for clinicians. Approved by the American Psychological Association, this program is designed to provide “a thorough understanding of how to ethically, safely, and legally use nutritional psychology to inform clinical practice and learn when and how to refer to other integrative medicine professionals.” Courses in the program look at how nutrition affects the most common mental health disorders, including major depression, bipolar disorder, schizophrenia, autism, obsessive-compulsive disorder, and ADHD. The program also addresses how nutritional psychology knowledge can be integrated into clinical practice.

Using Food as an Augmenting Agent
Psychiatrist Brad Zehring, DO, is CEO and cofounder of Arizona Restorative Psychiatry, a clinic that treats mental health disorders (e.g., depression, schizophrenia, and bipolar disorder), eating disorders, and sleep disorders. Its holistic approach to treatment takes into account how dietary changes can help to balance moods, sharpen brain function, and improve mental health.

In his article “The Importance of Nutrition in Psychiatric Treatment,” published at the website Psychiatry Advisor, Zehring cites the impact of vitamins and minerals on brain function, cognition, and neurotransmitter metabolism. He states, “There is enough research that suggests a correlation between many mental disorders and poor nutritional intake,” and he advises that mental health professionals stay up to date on the latest research in the field.

Zehring continues, “While using food as treatment in lieu of medications seems extreme, there is definitely a place to talk about nutrition with our patients and use food as augmenting agents to medications and psychotherapy.”

The assessment that food may be used as an augmenting agent or adjunct treatment for mental health issues is a good summation of where the field of nutritional psychology stands today. The impact of food and nutrients on the body certainly warrants attention within an integrated holistic approach to health and well-being. At the same time, there is a strong need for more research. For example, regarding the role of supplementation with omega-3 fatty acids, it has been stated that “an overall consensus about their efficacy is still lacking” and the findings of most trials are “controversial and inconclusive” (Bozzatello et al, 2016).

The human body is complex, and there is still much to be learned about all the biochemical processes that take place within it. As health care specialists and patients continue to embrace the shift towards more holistic patient care, interest in nutritional therapy from all corners will likely grow in the coming years, as will the demand for more rigorous research to better inform future mental health interventions.

— Susan A. Knight is a freelance writer with a focus on health and wellness.


Arroll, M. A., Wilder, L., & Neil, J. (2014). Nutritional interventions for the adjunctive treatment of schizophrenia: A brief review. Nutrition Journal, 13, 91.

Bozzatello, P., Brignolo, E., De Grandi, E., & Bellino, S. (2016). Supplementation with omega-3 fatty acids in psychiatric disorders: A review of literature data. Journal of Clinical Medicine, 5(8), E67.

Lakhan, S. E., & Vieira, K. F. (2008). Nutritional therapies for mental disorders. Nutrition Journal, 7, 2.

Lewis, J. E., Tiozzo, E., Melillo, A. B., Leonard, S., Chen, L., Mendez, A., et al. (2013). The effect of methylated vitamin B complex on depressive and anxiety symptoms and quality of life in adults with depression. ISRN Psychiatry, 2013, 2013, 621453.