Gut-Brain Axis - How Your Gut is Affecting Your Mood and Mental Health

by Dr. Nick Zyrowski May 19, 2022

Have you ever experienced what most call a “gut feeling” or have had “butterflies” in your stomach? These sensations radiating from your belly suggest that your brain and gut are connected. What’s more exciting is that recent studies have shown the gut has been called a "second brain" because it produces many of the same neurotransmitters as the brain does, like serotonin, dopamine, and gamma-aminobutyric acid, all of which play a key role in regulating mood. Let’s dive deeper and explore further how gut health affects your brain health, what causes disruptions, and how to combat those disturbances.

What is The Gut-Brain Axis?

The gut-brain axis refers to the physical and chemical connections between your gut and brain. Millions of nerves and neurons run between your gut and brain. Neurotransmitters and other chemicals produced in your gut also affect your brain.

The gut-brain axis essentially is a two-way connection and communication between the gut and the brain. What is happening in the gut can directly influence our brain function and behavior. An imbalance within the microbiome (which is the collection of all microbes, such as bacteria, fungi, viruses that naturally live on our bodies and inside us) and inflammation of the gut have been linked to causing several mental illnesses including anxiety and depression, which are very common in society today.

How Does Your Gut and Brain Communicate?

There are three main pathways that formulate the gut-brain axis: nerves, neuroendocrine system, and immune system.


Nerves connect to the gastrointestinal (GI) tract and allow communication signals to flow between the gut and the brain. The vagus nerve acts as the major communication line to the gut and it is affected by movement of your GI tract, as well as the activity of your gut microbes, hormones, and neurotransmitters. Vagus nerve activity has been linked to mood regulation. The enteric nervous system, which is a network of nerves found throughout the walls of your GI tract, also plays a key role in gut-brain communication. The bacteria in your gut also make molecules that like short-chain fatty acids and neurotransmitters. Neurotransmitters are chemicals that transfer impulses from nerve fibers. The activity of certain neurotransmitters affects areas of the brain, which can in turn, affect our mood and behavior.


Your gut microbes also affect the production of hormones involved in the stress response, metabolism, and mood. Gut bacteria also make short-chain fatty acids (SCFAs) by breaking down fiber. SCFAs help your body by fighting off inflammation. Many mental health disorders have been linked to high levels of inflammation within the body.


As we mentioned, the microbiome is the collection of all microbes, such as bacteria, fungi, viruses, and their genes, that naturally live on our bodies and inside us. Your gut microbiome is an important part of the protective mucus layer within your gut. Having a decrease of healthy bacteria can lead to a weaker mucus layer in the GI tract, which makes it easier for inflammatory molecules to pass through. This can contribute to higher levels of inflammation throughout the body, including the brain.

How does Gut Health Affect Mental Health?

If someone is suffering from gastrointestinal problems and symptoms, and they’re also finding that they have different problems with focus and memory and cognitive issues – then the Gut-Brain Axis is affected. And when the Gut-Brain Axis is affected, it can not only cause psychiatric disorders, psychological disorders – it can also affect your mood, it can affect your memory, it can affect the amount of brain energy you have on a daily basis. Let’s go ahead and talk about some of the different symptoms that would indicate that you have this issue going on:

  1. Discomfort after meals: every time you eat a meal, you’re getting a lot of pain and discomfort, then there’s a good chance that there’s an issue with your overall gut health affecting your brain health.
  2. Distening after meals: let’s say you’re a skinny person. You eat a meal and you just have so much distention that you look like you’re fat when you’re really not.
  3. Food intolerances: a lot of people have a couple foods that they are intolerant to. Let’s say somebody is intolerant to dairy. Sometimes, people have a couple of them. But if you’re finding that you’re having a whole string of intolerances, then there’s a good chance, once again, that there is a gut condition that you are facing and what we have to really be aware of is if the Gut is on Fire then the Brain is on Fire.

Now, looking at problems like Stress, Anxiety, Parkinson’s, Bi-Polar Disorder, Memory issues, Focus issues, Schizophrenia, Autism, all these different disorders are being linked to gut conditions. Whether it’s a deficiency in a certain strain of bacteria, an increase of inflammation, or there’s pathogens or parasites in the gut. When we go in and start actually removing some of these issues, we’re finding that these problems are starting to reverse themselves, clinically.

Top Strategies To Heal Your Gut

When we have gut and microbiome imbalances, it takes more than just wishful thinking to reverse these issues. We’ve found that taking clinically-relevant doses of specific nutrients allows the body to heal and recover at a more rapid rate. Who wouldn’t want that?! Some amazing options to consider are:

  1. Probiotics - There’s substantial evidence that probiotics can help with diarrhea, constipation, ulcerative colitis, IBS, and other functional GI disorders such as SIBO. What’s more is that probiotics have the potential to positively influence the natural state of well-being and neurological health.
  2. L-glutamine- The most abundant amino acid in the body, L-glutamine plays an important role in maintaining the gut lining. It can help repair the tight junctions between the cells in the lining of the GI tract that are damaged by leaky gut syndrome.
  3. Omega-3 Fatty Acids - Omega-3s have been shown to help improve the balance of good and bad bacteria in the gut microbiome in people with inflammatory bowel disease, as well as boost production of anti-inflammatory compounds that help heal leaky gut. Omega-3 fats are also crucial for proper brain function, as our brains are made up of 60% fats.
  4. Digestive enzymes - It is more important now more than ever to make sure you're receiving all the nutrients you can out of food for your body and mind. Using digestive enzymes can support digestion, let your body get the nutrients it needs, and help keep the brain happy. Supplemental enzymes have been shown to help with a variety of postmeal discomforts, including diarrhea, bloating, and flatulence.

Additional Tips for Optimizing Gut and Brain Health

  1. Focus on fiber. Keep your gut bacteria happy and nourished by giving them their favorite food - fiber. High-fiber foods include fruits, vegetables, and seeds.
  2. Don’t forget fluids. When fiber passes through your intestinal tract, it absorbs water, which can lead to constipation and discomfort if you’re not drinking enough fluids. Set a water goal that works for you and try to sip throughout your day.
  3. Exercise matters, too. Being physically active can improve both your mental and your gut health. Aim to do some form of physical activity each day - anything counts!
  4. Include anti-inflammatory foods. Gut health, inflammation, and mental health are all closely linked. Help your body fight inflammation by including anti-inflammatory foods like walnuts, flaxseeds, chia seeds, salmon, berries, and green tea.

Bridging the Gap

An imbalance within the microbiome and inflammation of the gut have been linked to causing several mental illnesses including anxiety and depression, but by altering the types of bacteria in your gut it’s possible to improve your overall brain health. Taking steps to heal our gut and thereby improving our brain health is a powerful and effective way to maximize our whole body health. If you are looking for more one-on-one assistance with balancing your gut and brain, consider working with a holistic practitioner.

References :

    Dr. Nick Zyrowski
    Dr. Nick Zyrowski

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