The Impact of the Gut-Brain Connection and Specific Nutrients on Mental Health

Rates of major mental health disorders from ADHD to depressions to eating disorders are increasing. There are many factors from our diets, social media and environmental toxins that contribute to this epidemic. The positive side, is that we are also talking about it more and there is more research around this subject, one of them being the importance of nutrients for our mental wellbeing.

Our mental health is intrinsically linked to the health of our bodies. Emerging research is revealing how the foods we eat can have a profound impact on our mood, cognition, and overall mental wellbeing.

The Gut-Brain Axis

The gut-brain axis refers to the bidirectional communication that occurs between the gastrointestinal tract and the central nervous system. This connection allows the gut to send signals to the brain and the brain to send signals to the gut, creating an intimate relationship between digestive health and brain function. There’s a reason why out ‘gut feeling’ is often right!

One of the key ways the gut communicates with the brain is through the gut microbiome - the trillions of bacteria, viruses, and other microorganisms that reside in our intestines. These gut microbes produce neurotransmitters like serotonin, dopamine, and GABA, which play crucial roles in regulating mood, focus, and other cognitive processes. An imbalance in the gut microbiome has been linked to conditions like depression, anxiety, and cognitive decline (1). Moreover, the Standard American Diet (SAD) is often void of nutrients but rather filled with inflammatory foods and sugars like bread, pasta, burgers and fries, placing a direct strain on the gut.

Probiotics

Probiotics, the beneficial bacteria found in fermented foods and supplements, have been shown to have a positive impact on mental health by supporting a healthy gut microbiome. Studies have found that probiotic interventions can help alleviate symptoms of depression and anxiety, improve cognition, and even reduce stress levels (2).

Probiotics may modulate neuroinflammation, alter neurotransmitter production, and reduce oxidative stress - all of which can have downstream effects on mood and cognitive function (3). As you can also have a bacterial overgrowth, it’s sometimes best to consult your functional medicine practitioner to conduct a stool analysis to have a deeper dive and understanding into the specific probiotics you may need.

Lithium (& other minerals)

Although we often forget about lithium as a key nutrient. Lithium is essential for human health in small amounts. Prescription lithium (up to 1800mg) has long been used as a treatment for bipolar disorder, but it may also have broader applications for supporting brain health, including addictions, depression and even aggression. At low, nutritional doses like 1-2mg, lithium has been shown to promote the growth of new brain cells, protect against neurodegeneration, and even improve memory and cognition (4). A meta-analysis from across 2678 regions containing 113 million people demonstrated the amount of lithium in the tap water had a correlation to suicide rates. Higher lithium had lower rates of suicide and vice versa (5).

The neuroprotective effects of lithium are thought to be due to its ability to reduce inflammation, increase antioxidant defenses, and regulate key signaling pathways in the brain. Hair tests are best to test for lithium levels along with other minerals, like magnesium, which plays a crucial role in regulating the stress response, neurotransmitter function, and neuroplasticity as well as zinc which is necessary for the production of neurotransmitters and the maintenance of the blood-brain barrier,

Omega-3s and Depression

Omega-3 fatty acids, particularly EPA and DHA, have been extensively studied for their potential benefits in supporting mental health. Several meta-analyses have found that omega-3 supplementation can be an effective adjunct treatment for depression, with higher doses (around 1-2 grams per day) showing the most promising results (6).

The mechanisms by which omega-3s influence mood are multifaceted. These essential fats help reduce inflammation in the brain, support neurotransmitter function, and even promote the growth of new brain cells. Omega-3s may also help to stabilize cell membranes and improve the brain's response to stress (7).

B Vitamins and Brain Function

B vitamins, especially B12, folate, and B6, play crucial roles in supporting cognitive function and mental health. Deficiencies in these vitamins have been linked to an increased risk of depression, cognitive impairment, and dementia (8).

B vitamins are involved in the production of neurotransmitters, the regulation of homocysteine levels (which can be neurotoxic in high amounts), and the metabolism of fats and proteins that fuel the brain. Ensuring adequate intake of B vitamins through diet from lean meats, eggs, tofu and nuts and seeds or supplementation can help optimize brain health.

Amino Acids

Amino acids also play a crucial role in mental health. Some amino acids, such as tryptophan and tyrosine, are precursors to neurotransmitters like serotonin, dopamine, and norepinephrine, which are responsible for regulating mood, sleep, and cognitive function.

For example, tryptophan is a precursor to serotonin, a neurotransmitter that helps regulate mood, sleep, and appetite. Low levels of serotonin have been linked to depression and anxiety. By ensuring adequate tryptophan intake, individuals can support healthy serotonin levels and potentially improve their mental well-being.

Addressing Inflammation and Toxins

Chronic inflammation in the brain has been linked to a wide range of mental health disorders, from depression and anxiety to cognitive impairment and dementia. Inflammation can be exacerbated by various factors, including a poor diet, exposure to environmental toxins, and underlying health conditions (9). We know that inflammatory markers in the brain predict suicide which is becoming in a leading cause of death in teenage boys (10).

Incorporating anti-inflammatory foods, such as those rich in omega-3s, antioxidants, and polyphenols, can help reduce neuroinflammation and support overall brain health. Additionally, reducing exposure to toxins, such as heavy metals, pesticides, and air pollution, may also have a positive impact on mental wellbeing.

In conclusion, the foods we eat and the nutrients we consume have a profound impact on our mental health and cognitive function. It’s important to note that doses are important when it comes to healing. Testing levels in your body with your functional medicine practitioner so you can supplement with doses specific to your body’s needs is always advised. In short, by nourishing our bodies, supporting the gut-brain connection, and nurturing our emotions by practicing stress relieving techniques, we can potentially prevent or mitigate the effects of various neurological and psychiatric conditions.

References:
(1) Dinan, T. G., & Cryan, J. F. (2017). The Microbiome-Gut-Brain Axis in Health and Disease. Gastroenterology Clinics of North America, 46(1), 77–89.  

(2) Messaoudi, M., Lalonde, R., Violle, N., Javelot, H., Desor, D., Nejdi, A., Bisson, J. F., Rougeot, C., Pichelin, M., Cazaubiel, M., & Cazaubiel, J. M. (2011). Assessment of psychotropic-like properties of a probiotic formulation (Lactobacillus helveticus R0052 and Bifidobacterium longum R0175) in rats and human subjects. The British Journal of Nutrition, 105(5), 755–764.  

(3) Liu, Y. W., Liu, W. H., Wu, C. C., Juan, Y. C., Wu, Y. C., Tsai, H. P., Wang, S., & Tsai, Y. C. (2016). Psychotropic effects of Lactobacillus plantarum PS128 in early life-stressed and naive adult mice. Brain Research, 1631, 1–12.

(4) Forlenza, O. V., De-Paula, V. J., & Diniz, B. S. (2014). Neuroprotective effects of lithium: implications for the treatment of Alzheimer's disease and related neurodegenerative disorders. ACS Chemical Neuroscience, 5(6), 443–450.  

(5) Eyre-Watt B, Mahendran E, Suetani S, Firth J, Kisely S, Siskind D. The association between lithium in drinking water and neuropsychiatric outcomes: A systematic review and meta-analysis from across 2678 regions containing 113 million people. Australian & New Zealand Journal of Psychiatry. 2021;55(2):139-152.

(6) Appleton, K. M., Hayward, R. C., Gunnell, D., Peters, T. J., Rogers, P. J., Kessler, D., & Ness, A. R. (2010). Effects of n-3 long-chain polyunsaturated fatty acids on depressed mood: systematic review of published trials. The American Journal of Clinical Nutrition, 84(6), 1308–1316.

(7) Guu, T. W., Mischoulon, D., Sarris, J., Hibbeln, J., McNamara, R. K., Hamazaki, K., Freeman, M. P., Maes, M., Matsuoka, Y. J., Belmaker, R. H., & Jacka, F. N. (2019). International Society for Nutritional Psychiatry Research Practice Guidelines for Omega-3 Fatty Acids in the Treatment of Major Depressive Disorder. Psychotherapy and Psychosomatics, 88(5), 263–273.  

(8) Tolmunen, T., Hintikka, J., Ruusunen, A., Voutilainen, S., Tanskanen, A., Valkonen, V. P., Viinamäki, H., Kaplan, G. A., & Salonen, J. T. (2004). Dietary folate and the risk of depression in Finnish middle-aged men. A prospective follow-up study. Psychotherapy and Psychosomatics, 73(6), 334–339.  

(9) Capuron, L., & Miller, A. H. (2011). Immune system to brain signaling: neuropsychopharmacological implications. Pharmacology & Therapeutics, 130(2), 226–238.

(10) Brundin L, Bryleva EY, Thirtamara Rajamani K. Role of Inflammation in Suicide: From Mechanisms to Treatment. Neuropsychopharmacology. 2017 Jan;42(1):271-283. doi: 10.1038/npp.2016.116. Epub 2016 Jul 5. PMID: 27377015; PMCID: PMC5143480.

Denise Tam
Certified Holistic Nutritionist


Denise Tam is a Certified Holistic Nutritionist, an Integrative Mental Health Coach in training with the Nickerson Institute and a member of the Canadian Association Natural Nutritional Practitioners. Having completed a certification for Applying Functional Medicine in Clinical Practice with the Institute for Functional Medicine and being a two-time stage 4 cancer survivor, Denise brings a wealth of knowledge and personal passion and experience to her practice.  Denise is a contributing author to "Saved by Nutrition" and a sought-after speaker, having shared her story with organizations like Morgan Stanley, EY and HSBC.

She is passionate about inspiring and working with people to pursue an unconventional approach to health care, one that focuses on optimal health and prevention rather than disease.

Blog Post written by:

The Nickerson Institute of Integrative Health Training deeply appreciates the contribution of this article from our guest health professional. If you would like to submit an article for consideration, please visit https://www.nickersoninstitute.com/blog-contributor-form

More Articles

Epigenetics and Generational Trauma: Unraveling the Biological and Environmental Influences
What Happened? Was it an Emotional Trigger, a Past Life Reaction, or a Shift in Timelines?
Ghostlighting: The Spiritual Sleight of Hand
From Hiding to Healing: How Executives Can Find Their Authentic Power