Linking Nutrition to Mental Health

The term “Nutrition for Mental Health” has broad implications. One might assume it is merely about nutrients (e.g., vitamins and minerals) that are important for optimal brain health and functioning. While nutrients themselves are quite important biological factors for cognitive processes, there is actually much more to it!

This article is an introduction to the conversation around nutrition and mental health. Many of the nuances will be expanded on and covered in future articles. Please subscribe to stay up-to-date with this exciting new area of study (“Nutritional Psychology”) and clinical practice (“Nutritional Psychiatry”).

Mental Health Vs Nutrition

“Mental health” is also a broad term. It includes disorders such as depression, anxiety, substance use disorders, post-traumatic stress disorder, attention deficit hyperactivity disorder, and more. Importantly, mental health also includes “mental wellness” which can be independent of known stress-related, behavioral, or mood disorders.

The term “nutrition” is also a broad domain. It includes food but also includes dietary supplements, nutraceuticals such as polyphenols, and other compounds that can be ingested and digested. Thus, the link between nutrition and mental health can take on various forms, depending on context. Here, we focus on mental health conditions with known links to nutritional status and/or eating behavior.

Linking Nutrition and Mental Health

Many of the early scientific discoveries (that caught my attention) linking nutrition to mental health came from associational studies linking various micronutrient deficiencies to a range of mental health disorders. For example, individuals using drugs and/or alcohol present to hospital detoxes with a wide range of nutrient deficiencies such as B-vitamins, antioxidant vitamins (A, C, and E), magnesium, iron, etc. [1–4]. Importantly, some nutrients such as copper and zinc can be elevated (rather than deficient) indicative of potential infection and inflammation. Meanwhile, associational studies cannot indicate if the micronutrient deficiencies are a cause or a consequence of the impairments in mental status. And of course, drug and alcohol use are both associated with altered eating behavior and gut function therefore such findings cannot be extrapolated to the general population.

A growing body of research in the area of Nutrition for Mental Health focuses on depression-related outcomes. Countless studies have shown that the Mediterranean Diet has been associated with reductions in depressive symptoms [5,6]. Recently, intervention trials have been conducted using broad spectrum micronutrient formulas for symptoms of depression, stress, and anxiety, with the majority of studies showing positive effects [7]. For example, B-vitamin supplementation has been shown to benefit stress management in at-risk populations [8]. It has also been suggested that long-term consumption of micronutrients for the treatment of psychiatric symptoms is safe, without reports of clinically significant adverse effects [9]. Efforts to improve diets and/or include supplementation should be routine in clinical mental health care, but it is unfortunately not!

A recent meta-analysis showed that dietary interventions using food hold promise as a novel intervention for reducing depressive symptoms across multiple different groups in the population [10]. Importantly, intervention studies using food-based interventions differ from dietary supplement studies in several ways. One obvious difference is that changing the way people eat is much more difficult than adding a daily pill regimen. Another example is that food has profound implications for gut bacteria, which will be discussed in much more detail in future articles.

As stated, there is so much “more to it” than food and nutrients. This conversation must go beyond the biochemical reductionist approach. For example, how we think about food also falls under the domain of Nutrition for Mental Health. If an individual is spending 50% of the day stressing out about food and/or their body, it can certainly impact mental health and overall quality of life.

Another example is the recent discovery of the gastrointestinal tract as the “second brain” which has broad implications for the immune system and therefore all body systems. The psychology of eating, the concept of eating to feed microbes that live inside of us, are all part of a much-needed paradigm shift in the field of nutrition. What an exciting time to translate research into findings that can actually help people improve the quality of their lives today!

To summarize, there is a biological lens for Nutrition for Mental Health related to nutrients and physiological processes that are connected to the brain (sometimes referred to as Nutritional Psychiatry [11]). There is a psychological lens that is related to body image, disordered eating, and cognitive processes around food choices (sometimes referred to as Nutritional Psychology [12]).

There is also a sociocultural lens that connects food to the human experience, situated in family dynamics, communities, and the broader ecological context of our environment (sometimes referred to as the Social Determinants of Health [13]). It is critical to merge all of these perspectives and employ a Biopsychosocial Model to the conversation of Nutrition for Mental Health. The conversation is just beginning. Be here for it!

References
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