The Gut-Brain Connection

The Gut-Brain Connection
Katie Breazeale, MS, RD, LD



Your gut, or to be more specific, the microbiome of your gut is a major player in your body’s health. It’s as old as you are, forming from birth.  The microbiome in our small and large intestines is huge!  There are not thousands, but trillions of different bacteria, fungi, yeast, and viruses. Here, we will go through different ways your gut can affect your body:


  1. Immune System:  80% of our immune-producing cells live in our intestinal tract. With 80% of our immune-producing cells being in the gut that allows our gut to communicate with these cells and control how the body will respond to the infection.  
  2. Weight:  When the gut has more bad bacteria than good, or an imbalance, there can be an increase in weight gain.  The disbalance can affect how nutrients are absorbed, metabolized, and stored.
  3. Heart Health:  Research has shown a happy gut can promote HDL (good) cholesterol.  On the flip side when the gut is at a healthy balance it can produce TMAO, trimethylamine N-oxide.  TMAO is a chemical that plays a role in blocking arteries.  
  4. Brain Health:  Did you know that serotonin, which is an antidepressant neurotransmitter, is made in your gut? (Roughly 80%) If your gut is off balance, it could increase your risk for depression and anxiety.  The gut is also connected to the brain through millions of nerves.  What does that mean?  The gut can control messages that are sent to the brain through all those nerves. Have you ever been stressed, and it caused you to have diarrhea, or maybe you were nervous, and it caused you to vomit.  These are examples of the gut brain connection.   
  5. Gut Health:  Needless to say, your gut microbiome affects your gut health.  When a disbalance occurs, it can affect IBS or IBD.  Disbalance can be seen with excess bloating, cramps, and abdominal pain.
  6. Blood Sugar Regulation:  While research is not as comprehensive in this area there are studies showing that when there was a disbalance in the gut, or a drop in diversity of the microbiome, the person developed diabetes shortly after.  Also, different gut microbiomes displayed different blood sugar readings based on the different types of bacteria in the gut.
  7. Inflammation:  Research has shown that our gut microbiome may play a role in inflammation in the body.  Certain bacteria can cause inflammation, but also certain conditions like obesity, diabetes, IBD, and atherosclerosis have inflammation linked to them.  These are all diseases that can be affected by the gut.  


What are some ways we can improve the gut-brain connection?  

Diversity with your diet. When you eat a diet that is diverse, meaning  a diet that is full of different fruits, veggies, whole grains, and meats, your gut is able to build a diverse microbiome.  This is the ideal gut situation.  The more diverse the bacteria in your gut the more health benefits you will ha

Increase your fiber intake. Fruits and vegetables offer the most benefits for your gut health.  Fiber encourages the growth of good bacteria in your stomach.  Prebiotics is a term used interchangeably with fiber and are natural, non-digestible food components that are linked to promoting the growth of helpful bacteria in your gut. Simply said, they’re “good” bacteria promoters. Fiber can be found in raspberries, artichokes, broccoli, beans, lentils, bananas, apples, and prunes.

Try fermented foods.  Fermented foods are where the food item has had the sugar content broken down by bacteria or yeast.  Have you ever been advised to eat yogurt to help your gut health? There is science and research showing that people who ate yogurt regularly had higher amounts of good bacteria in their gut.  Other fermented foods include kimchi, kefir, kombucha, tempeh, and sauerkraut.  

Probiotics for gut balance. Probiotics are the “good” bacteria — or live cultures — just like those naturally found in your gut. These active cultures help change or repopulate intestinal bacteria to balance gut flora. This functional component may boost immunity and overall health, especially GI health.  For those not interested in fermented foods another way to get probiotics is through over the counter gummies or capsules. Ultimately, prebiotics, or “good” bacteria promoters, and probiotics, or “good” bacteria, work together synergistically. Products that combine these together are called symbiotic. On the menu, that means enjoying bananas atop yogurt or stir-fried asparagus with tempeh is a win-win.

Eat foods rich in polyphenols. Polyphenols are compounds found in plant-based foods.  They offer the body benefits of reduced free radicals, blood pressure, inflammation, cholesterol, and oxidative stress.  These compounds increase the number of good bacteria in the gut.  Foods rich in polyphenols include dark chocolate, green tea, cocoa, almonds, blueberries, onions, and broccoli. 

There are so many ways to help our gut-brain connection knowing where to start, or what the best option is can be challenging. I believe the best place to start is the diversity of your diet.  Increasing whole grains, fruits and vegetables, and limiting processed and high fat foods.