The Gut-Brain Connection: Nutrition is Medicine

What if someone told you that your kitchen has the potential to be a medicine cabinet?  That within the confines of your pantry and refrigerator are items that provide not just for your physical nourishment but also for your mental well-being?  The fascinating complexity of the gut-brain connection, and its impact on mental health, is progressively being discovered through research.  Nutrition is medicine.

My interest on this topic began to develop while I was a student in a Masters in International Health program some years ago.  The coursework on nutrition, particularly as it relates to preventative healthcare, held specific fascination for me.  It was only natural, therefore, that the connection between mental health and nutrition would be of interest to me as a counselor.  Please note, however, that I am not a dietician, nutritionist or medical doctor, nor have I received formal training in nutrition as it relates specifically to mental health.  This blog is intended for informational purposes only and not as medical advice.

What is the Gut-Brain Connection?

Our guts are regulated by the enteric nervous system (ENS), which has been referred to as the ‘second brain’ of the body.  The ENS controls the entire digestive system through a network of more than 100 million nerve cells which line the intestinal tract. This network is responsible for ensuring our bodies digest food particles and absorb nutrients. Furthermore, it is also responsible for sending messages from the gut to the central nervous system (CNS).  Therefore, the next time you have the sensation of ‘butterflies’ in your stomach, you may wish to take a moment to consider the emotions that are impacting your gut through this complex network!

The gut is also the production site for much of the body’s neurotransmitters, such as GABA, serotonin and dopamine, which are vital for healthy brain chemistry.  Proper digestion of food particles is essential for the creation of these neurotransmitters. When the gut is not working efficiently, mental health suffers.

Additionally, the gut is home to an entire ecosystem of bacteria.  When in a state of optimal health, friendly bacteria flourish and keep unfriendly bacteria in check.  These microbiota aid in the production and secretion of neurotransmitters and play a vital role in the body’s stress regulation.  The make-up of our gut flora can also manipulate the food choices that we make, dependent on their particular nutritional needs.  The influence of too many unhealthy bacteria left unchecked can result in one experiencing greater difficulty making healthy food choices.

Maintaining a healthy gut ecosystem, is vital, therefore, whether through probiotic supplementation or natural food sources.  You could consider having fun experimenting with homemade ferments such as sauerkraut, kimchi, yogurt, kefir, or kombucha to aid in regulating and re-establishing gut microbiota.

How the Gut-Brain Axis Impacts Mental Health

Various mental health concerns, including anxiety and depression, have been found to have a high comorbidity with chronic digestive issues. As Dr. Leslie Korn states in Nutrition Essentials for Mental Health, “Where there is mental illness, there is a long history of digestive problems.” This could be related to a number of issues, including chronic inflammation in the body and dysbiosis in the gut microbiota.

A poor, nutritionally deficient diet contributes to inflammation in one’s body.    Chronic, low-grade inflammation keeps cell immune secretions turned on, resulting in the ongoing production of proteins called cytokines. Pro-inflammatory cytokines, triggered by foods such as sugar, are known to trigger the hypothalamic-pituitary-adrenal (HPA) axis, encourage neuroprogression, and disrupt the functioning of neurotransmitters and the metabolism of serotonin – all of which are relevant for mental health!  According to Dr. Jay Pasricha, director of Neurogastroenterology at the John Hopkins Center, research also indicates that when the gastrointestinal system is inflamed, messages being sent from the ENS to the CNS can activate shifts in mood.  Making health food choices, therefore, is vital for nourishing our brains.

Various studies have linked inflammation in the body to mental health illnesses.  For instance, Dr. Jennifer Felger reports in Imaging the Role of Inflammation in Mood and Anxiety-related Disorders on the connection between elevated biomarkers of inflammation with anxiety disorders, major depressive disorder (MDD), post-traumatic stress disorder (PTSD) and bipolar disorder. Some other factors which lead to inflammation in the body include gut permeability, vitamin D deficiency, and stress. Stress further disrupts system functioning as the activation of the fight or flight response inhibits the secretion of digestive enzymes, weakens the contractions of the digestive muscle, as well as transmits blood flow away from digestive organs.

The importance of one’s gut microbiota make-up for brain functioning also cannot be overstated. Dysbiosis in the gut microbiome occurs when there is a loss of bacteria diversity, including a decrease of healthy bacteria and increase of pathogenic bacteria.  Dysbiosis has been correlated with an increase in anxiety and depression, as well implicated in other mental health disorders.  This is not surprising due to the role healthy gut bacteria play in the regulation of various neurotransmitters such as GABA, which is a stress-reducing and relaxation-promoting neurotransmitter.

Cultivating our Guts for Better Brain Health

Fortunately, we have been provided with natural food sources to cultivate good gut health. Nutritious food is medicine!  Here are some ways to cultivate a healthier gut this year:

  1. Eat antioxidant-rich, colourful fruits and vegetables.
  2. Increase your intake of anti-inflammatory foods such as berries, fatty fish, dark leafy greens, tomatoes, olive oil, avocados, turmeric, and ginger.
  3. Eat nutrient-dense, traditional foods such as bone broth. Bone broth is highly nutritious, being rich in amino acids and collagen which are great for brain functioning.
  4. Replenish your gut with healthy probiotics (good bacteria) through supplements or eating fermented foods.
  5. Feed your gut microbiota with fiber-rich prebiotics, such as apples, bananas, garlic, dandelion greens, chia seeds, oatmeal or bran.
  6. Fuel the brain. The brain is 60% fat and needs sufficient fuel in the form of healthy fats, proteins and carbohydrates to operate well.
  7. Limit refined sugars and grains, synthetic preservatives and food colouring. Eat food that has been minimally processed.

Cultivating our Brains for Better Gut Health

De-Stress!!  Relaxation is necessary for proper digestion.

  1. Slow down and take a few deep breaths before your meal.
  2. Cultivate joy in life. Find ways to connect with those you love.
  3. Develop a couple new habits this year that promote relaxation. Be intentional about doing something you enjoy, whether that be going for a nature walk, taking an art class, gardening, journaling or catching up with a close friend.

Finally, a challenge this new year is to cultivate awareness of your emotions and choices.  The next time you peruse the aisles of the grocery store, pay attention to the items being placed in your cart. Is it primarily food that will promote your mental well-being by nourishing a healthy gut and brain?  Is it nutrient-dense, able to feed a healthy gut microbiota and promote the development of vital neurotransmitters?  Or is it mostly food that is feeding unfriendly bacteria, promoting inflammation and potentially leading to unhappy mental states?  If you’re finding it difficult to make healthy food choices, might I encourage you to pay attention to the emotions that could be underlying your drive towards certain foods, as well as be aware of how your current microbiota may be influencing you and focus on taking steps to replenish a healthy microbiome. You are worth providing your body with the fuel that will enhance your emotional and mental well-being!


Aslam, H., Green, J., Jacka, F. N., Collier, F., Berk, M., Pasco, J., & Dawson, S. L. (2020). Fermented foods, the gut and mental health: A mechanistic overview with implications for depression and anxiety. Nutritional Neuroscience23(9), 659-671.

Felger, J. C. (2018). Imaging the role of inflammation in mood and anxiety-related disorders. Current Neuropharmacology, 16(5), 533-558.

John Hopkins Medicine. (n.d.) The brain-gut connection.

Korn, L. (2016). Nutrition essentials for mental health: A complete guide to the food-mood connection. W. W. Norton & Company.

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