Do Critters in Your Gut Make You Anxious?

Dr. Emily Chan, ND

How does the intestinal micro biota affect your mood?

Learn the importance of addressing intestinal flora balance in treating anxiety. How can an organ so far away from your brain affect it so much? Well, it turns out that the bacteria in your intestinal tract help make neurochemicals. For example, 90% of the body’s serotonin is made in the gut. The balance of which bacteria is in your intestinal tract can highly affect the balance of brain chemicals in your body. When the levels of neurotransmitters are out of balance, patients experience problems such as anxiety, depression, brain fog, memory loss, ADHD to name a few. 

If you are experiencing anxiety and also symptoms such as bloating, food sensitivities, IBS, constipation, abdominal discomfort, and a sensitive stomach it is important to address the gut while treating anxiety in order to have more success in getting to the bottom of the problem. When addressing anxiety, it is also important to look at the adrenals, thyroid, hormone balance and certain mindset issues, previous emotional stressors, and traumas that trigger anxiety. But for today, we will focus in the gut.

How Much Bacteria Live Inside of Us?

We can have around 6 pounds of bacteria living in our gut. When there is overgrowth of bacteria, we call it SIBO. However, patients can have an imbalance of types of bacteria without having SIBO. This imbalance is called dysbiosis.

We have around 1014 bacteria living in our gut. To get some perspective in relationship to how much money is in the world total, we have 80 trillion dollars circulating around the world according to Market Watch in 2016. That includes cash, money in savings accounts, bank notes etc. One trillion has 12 zeros and we have 14 zeros of bacteria in our gut. We have 10 times more bacteria in our gut than number of cells in our body. So there must be some significance to how these critters affect us.

There are studies now that correlate the presence of certain types of bacteria with tendency to obesity. Over 4000 studies related to microbiota have been published from 2010-2015. Today we will focus on the relationship between microbiota and anxiety.

Lactobacillus Rhamnosus and GABA

GABA is a great neurotransmitter. It is the OFF switch of the nervous system and patients with anxiety often do not have enough GABA, or they have too much other excitatory neurotransmitters. GABA helps a person settle down, feel calm, feel safe and stop the fight and flight response. Certain prescription medications that affect the GABA pathway include Klonopin, Xanax, Valium, and Gabapentin. But these medications are often addictive and have unwanted side effects. It’s best that your body makes it’s own GABA. The probiotic Lactobacillus rhamnosus makes GABA. L rhamnosus can be a GABA making machine in the body if a patient has enough of this strain in their gut.

An animal study shows that treatment with L rhamnosus decreased activity in the hippocampus, amygdala and local coeruleus. Lactobacillus rhamnosus also reduced the stress response associated with cortisol. Therefore supplementation with L. rhamnosus is promising for supporting the body in making more GABA via the bacteria producing it. 

Chicken or Egg

With the evidence in this article, it is clear that the bacteria in the gut can affect anxiety and mood. But what about the other way around? Does stress and anxiety change the bacterial balance in the gut? The answer is yes. In the journal, Brain Behavior and Immunity, exposure to stress changes the composition and diversity of the intestinal flora. Therefore, in addressing anxiety, it is important to selectively supplement with the appropriate probiotic, and address intestinal issues. It is equally important to address the mindset, so that the perception of stress is not excessive in order to holistically treat anxiety disorders.


Dr. Emily Chan ND received her doctorate of Naturopathic Medicine from Bastyr University. She is a board-licensed naturopathic doctor and founder of Modern Integrative Medicine. She currently practices in San Diego, CA and consults around the world. Dr. Chan specializes in chronic medical conditions that have an impaired body memory component to them. She integrates the immune/nervous system and physiological relationships in treating her patients. She is published in medical journals, and magazines. She is a speaker, and has presented at medical conferences training doctors, and has appeared on television. She also authors and teaches health, and body memory reprogramming courses. Contact her at http://www.modernintegrativemedicine.com

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top