How Clostridia Overgrowth May Influence Your Mental Health

In my telehealth functional medicine clinic, I see a lot of people with ongoing mental health problems. Although I’m not a counselor, depression, anxiety, OCD, brain fog, and more are all conditions I walk through with my patients on a daily basis because the root cause is often more nuanced than conventional medicine makes it seem.

One of the lesser-known but silent drivers of mental health problems is something called Clostridia overgrowth. For many people, this seemingly unrelated gut problem is the missing piece of their mental health puzzle. From mood swings to complex neurological symptoms, clostridia overgrowth can manifest far beyond what you’d typically expect to see with gut dysfunction. 

But once you understand how this influences mental health, there’s hope. So let’s take a look at what clostridia overgrowth is, how it happens, its connection to mental health, and what steps you can take to finally reclaim your mental health once and for all. 

What is clostridia overgrowth?

Clostridia is a broad term for a larger group of over 80 different Clostridium gram-positive, anaerobic-bacteria strains. While this bacteria can oftentimes be found in small amounts in your gut microbiome, the problem happens when an imbalance happens between this opportunistic bacteria and the beneficial bacteria in your gut.

One of the most common examples of clostridia overgrowth is Clostridioides difficile. Also known as C. diff or C. difficile, it is often found in people who have spent long periods of time in the hospital and are taking antibiotics that deplete healthy bacteria levels, leaving the door open for C. difficile to thrive. Not only does this overgrowth cause extreme diarrhea, fever, abdominal pain, and nausea, it is extremely difficult to treat which can result in severe gut inflammation and damage to the large intestine over time.

Clostridium perfringens is another prominent strain of Clostridium, often referred to as C. perfringens. Infection with this strain occurs from eating undercooked or poorly prepared meat, and is the leading cause of food poisoning in America. Unlike C. difficile infections, symptoms of food poisoning (nausea, vomiting, diarrhea, etc.) typically go away after 24 hours. However, the effects of both types of Clostridium infections can continue to linger long after symptoms have subsided. Studies have found that even after antibiotic therapy, infections of Clostridium perfringens and C. difficile can result in long-term clostridia overgrowth, bacterial dysbiosis, and other chronic health problems like Inflammatory Bowel Disease. (1, 2)

What causes clostridia overgrowth?

There are many lifestyle factors and underlying conditions that can give way to clostridia overgrowth:

• Frequent antibiotic use: Antibiotics don’t just kill bad bacteria, they kill off the good bacteria in your gut too, putting you at risk for more infections (your gut is home to 75% of your immune system) and antibiotic resistance.
• Chronic stress: Stress doesn’t just impact you emotionally, it has also been linked to disruptions in gut health. (3) 
• Poor diet: Food intolerances, sensitivities, and more can all contribute to intestinal permeability (leaky gut syndrome) and a lack of important bacterial diversity in your gut.
• Underlying gut dysfunctions: Certain gut problems can make you more susceptible to bacterial dysbiosis.
• Eating undercooked/improperly prepared meat: Food poisoning from Clostridium perfringens happens to approximately 1 million people every year. (4) 

Understanding the gut-brain connection

The truth is, we can be dealing with other clostridium overgrowths without even realizing it. Just because you don’t have gut symptoms, doesn’t mean you don’t have gut problems. This is because your gut is the foundation of your entire health, including your brain health. Your gut and brain are inextricably linked through what is known as the gut-brain axis. What affects one affects the other. In fact, a whole area of research known as the cytokine model of cognitive function is dedicated to uncovering how the health of your gut impacts the health of your brain and vice versa. 

One of the biggest areas that we see this connection at work is with your neurotransmitters. Surprisingly, a significant portion of neurotransmitters like serotonin and dopamine are actually produced in your gut. So that’s why when your microbiome becomes imbalanced due to clostridia overgrowth, it can directly impact your neurotransmitters and how you feel mentally.

Clostridia overgrowth and mental health

Dopamine is one of your body’s most important neurotransmitters. It is responsible for everything from your mood to your memory. So when looking at how clostridia overgrowth impacts your mental health, we need to understand how it affects dopamine levels.

Studies have found that when clostridia overgrowth happens, it produces a neurotoxic metabolite known as HPHPA that blocks your body’s ability to convert dopamine into epinephrine and norepinephrine. (5) This results in excessive levels of dopamine because the metabolite interferes with key enzymes, which can cause symptoms such as:

• Anxiety
• Mood swings
• Paranoia
• Constipation
• Autism-related behaviors.

And since dopamine isn’t getting converted into important epinephrine and norepinephrine, low levels of these neurotransmitters are also linked to a variety of symptoms, such as:

• Brain fog
• Anxiety
• Depression
• Fatigue
• Mood swings

Clostridia overgrowth and autism

Considering the mechanisms behind how clostridia overgrowth impacts dopamine levels and autism-like behaviors, the majority of the research surrounding clostridia overgrowth is focused on its link to autism. One study found that children with autism had significantly higher levels of various Clostridium strains in their stool, along with having additional types of clostridium strains not found in the neurotypical children. (6) Research has also consistently found high levels of HPHPA in urine samples of children with autism. (7)

Clostridia overgrowth and schizophrenia

Since schizophrenia has long been associated with high levels of dopamine, it has prompted researchers to consider the connection between this condition and clostridia overgrowth. A recent study found that clostridia overgrowth correlated with a higher risk of schizophrenia. (8)

How to diagnose clostridia overgrowth

The most important thing you can do to support clostridia overgrowth is to run comprehensive labs to determine the overall health of your microbiome and if clostridia overgrowth is a factor in your specific case.

A stool microbiome test is the most common type of assessment for your gut. This kind of test uses your stool to analyze your microbial makeup to determine the presence of conditions like bacterial dysbiosis, candida overgrowth, and parasites.

An organic acid test (OAT) is a urine test that is particularly great for determining clostridia overgrowths. Some gut microbes, like strains of Clostridium, produce organic acids and since your body doesn’t reabsorb them, they get flushed into your urine. OAT can also measure your levels of dopamine, epinephrine, and norepinephrine.

READ MORE: Know Your Body Better: Here’s What Organic Acid Testing Can Reveal

How to support clostridia overgrowth

Once you know that clostridia overgrowth is a factor in your health case, you’ll want to take steps to restore microbiome balance. Thankfully, there are many ways you can promote the growth of beneficial bacteria and support overall gut health.

1. Eat more plant foods

If you need another reason to eat your vegetables, a study out of Stanford University found that microbiota-accessible carbohydrates (MACs) found in dietary plant polysaccharides — aka fiber and starch — were able to suppress Clostridium difficile infection in mice. (9) Some of my favorite fiber-rich plant foods include almonds, apples, avocados, Brussels sprouts, chia seeds, raspberries, and sweet potatoes.

2. Avoid any unnecessary antibiotic use

The Centers for Disease Control and Prevention (CDC) estimates that close to 30% of prescribed antibiotics are unnecessary and can continue to leave the door open for clostridium to thrive (especially in cases of C. diff). (10) If you are struggling with infectious diseases or other conditions where an antibiotic is an option, talk with your healthcare provider to see if there are any alternative therapies you can try first before going the pharmaceutical route.

Certain natural supplements like Otoba parvifolia and Huacapurana have long been used for their antimicrobial and antiviral properties. I personally formulated both my Otoba parvifolia and Huacapurana with the highest-quality plant extracts for both purity and effectiveness.

3. Consider a fecal transplant

Yes, I’m talking about a poop transplant. Medically referred to as a Fecal Microbiota Transplantation (FMT), this procedure involves collecting a stool sample from a donor with a healthy, balanced, and diverse gut microbiome and transferring it into the digestive tract of another patient with the goal of restoring their microbiome health and diversity.

FMT is currently only medically approved by the FDA for use in patients with C. difficile infections that no longer respond to antibiotics like vancomycin with a 90% success rate. (11) However, research is continuing to show promise in FMT for other conditions, specifically Autism Spectrum Disorder. In fact, a study published in the journal, Frontiers in Psychiatry, found that FMT was able to improve gastrointestinal and behavioral symptoms in children with autism. (12)

LISTEN: Dr. Steven Gundry: The New Microbiome Science (Bacterial Diversity, Pre vs. Pro vs. Postbiotics, Fermented Foods, Fecal Transplants, Saturated Fats, & More)

4. Target your supplements

If you haven’t reached the point of considering a fecal transplant, supplements are a much “tamer” option to start with. Synbiotics — a mix of both probiotics and prebiotics — have been shown to be particularly helpful in addressing clostridia overgrowths compared to being taken individually. This is due to the fact that both play a vital role in overall gut health, with probiotics reintroducing beneficial bacteria back into your gut and prebiotics acting as the fuel for them to thrive and multiply.

Studies have found that specific bacterial strains like Lactobacillus, Enterococcus, Bifidobacterium, and Saccharomyces are particularly beneficial at fighting against clostridia overgrowth by making it difficult for C. difficile to adhere itself and survive in your gut. (13) While the current research is mainly focused on prevention rather than treatment, ensuring your gut microbiome is fully armed with the proper bacteria it needs to thrive is an excellent first step.

Seeking help from a functional medicine expert

Research is continuing to draw the connection between these mental health conditions and the presence of clostridia overgrowth, so if you are struggling with ongoing mental health problems like anxiety, schizophrenia, or Autism, it is worth taking a deeper look into your gut health — it may just be the missing piece of your health puzzle. In my telehealth functional medicine clinic, we specialize in running comprehensive labs to assess the presence of clostridia overgrowth and tailor personalized plans to address the root cause of your mental health symptoms.

As one of the first functional medicine telehealth clinics in the world, we provide webcam health consultations for people around the globe. 

Photo: Unsplash.com

Sources

• Ba, X., Jin, Y., Ning, X., Gao, Y., Li, W., Li, Y., Wang, Y., & Zhou, J. (2024). Clostridium perfringens in the Intestine: Innocent Bystander or Serious Threat?. Microorganisms, 12(8), 1610. https://doi.org/10.3390/microorganisms12081610
• Bien, J., Palagani, V., & Bozko, P. (2013). The intestinal microbiota dysbiosis and Clostridium difficile infection: is there a relationship with inflammatory bowel disease?. Therapeutic advances in gastroenterology, 6(1), 53–68. https://doi.org/10.1177/1756283X12454590
• Beurel E. (2024). Stress in the microbiome-immune crosstalk. Gut microbes, 16(1), 2327409. https://doi.org/10.1080/19490976.2024.2327409
• Centers for Disease Control and Prevention. (2024, April 3). About C. perfringens food poisoning. https://www.cdc.gov/clostridium-perfringens/about/index.html
• Vinithakumari, A. A., Padhi, P., Hernandez, B., Lin, S. J., Dunkerson-Kurzhumov, A., Showman, L., Breitzman, M., Stokes, C., Sulaiman, Y., Tangudu, C., Kuttappan, D. A., Muyyarikkandy, M. S., Willette, A. A., Phillips, G. J., Anantharam, V., Perera, A., Sponseller, B. A., Kanthasamy, A., & Mooyottu, S. (2022). Clostridioides difficile Infection Dysregulates Brain Dopamine Metabolism. Microbiology spectrum, 10(2), e0007322. https://doi.org/10.1128/spectrum.00073-22
• Majidpoor, J., & Mortezaee, K. (2020). Steps in metastasis: An updated review. Journal of Molecular Neuroscience, 70, 897–907. https://doi.org/10.1007/s12031-020-01482-2
• Shaw W. (2023). Inhibition of the Beta-oxidation Pathway of Fatty Acids and Dopamine- Beta-hydroxylase by Phenyl Derivatives of Short- Chain Fatty Acids from Gastrointestinal Clostridia Bacteria is a (the) Major Cause of Autism. Integrative medicine (Encinitas, Calif.), 22(2), 18–25.
• Zhou, K., Baranova, A., Cao, H. et al. Gut microbiome and schizophrenia: insights from two-sample Mendelian randomization. Schizophr 10, 75 (2024). https://doi.org/10.1038/s41537-024-00497-7
• Hryckowian, A.J., Van Treuren, W., Smits, S.A. et al. Microbiota-accessible carbohydrates suppress Clostridium difficile infection in a murine model. Nat Microbiol 3, 662–669 (2018). https://doi.org/10.1038/s41564-018-0150-6
• Centers for Disease Control and Prevention. (2016, May 3). 1 in 3 antibiotic prescriptions unnecessary. https://archive.cdc.gov/www_cdc_gov/media/releases/2016/p0503-unnecessary-prescriptions.html
• Cheng, Y. W., & Fischer, M. (2023). Fecal Microbiota Transplantation. Clinics in colon and rectal surgery, 36(2), 151–156. https://doi.org/10.1055/s-0043-1760865
• Zhang, J., Zhu, G., Wan, L., Liang, Y., Liu, X., Yan, H., Zhang, B., & Yang, G. (2023). Effect of fecal microbiota transplantation in children with autism spectrum disorder: A systematic review. Frontiers in psychiatry, 14, 1123658. https://doi.org/10.3389/fpsyt.2023.1123658
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