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Evidence based

Evidence Based

This article is based on scientific evidence, written by experts and fact checked by experts.

Our team of licensed nutritionists and dietitians strive to be objective, unbiased, honest and to present both sides of the argument.

This article contains scientific references. The numbers in the parentheses (1, 2, 3) are clickable links to peer-reviewed scientific papers.

How the Mind-Gut Connection May Be Affecting You

Written by on June 14, 2022

Dr. Michael Ruscio is a DC, Naturopathic Practitioner, researcher, and clinician. He serves as an Adjunct Professor at the University of Bridgeport and has published numerous papers in scientific journals as well as the book Healthy Gut, Healthy You. He also founded the Ruscio Institute of Functional Health, where he helps patients with a wide range of GI conditions and serves as the Head of Research.

An In-Depth Look Into the Gut-Brain-Axis and Where It Can Go Wrong

Key Takeaways

  • The mind-gut connection is made of a network of nerves that allows the brain and digestive tract to communicate with each other.
  • An imbalanced gut microbiome and inflammation in the digestive tract can cause gut-brain-axis dysfunction, creating symptoms like brain fog, depression, and anxiety.
  • The brain regulates the movement of food through the digestive tract, and alterations in the brain (caused by stress) can disrupt GI function, such as in the case of irritable bowel syndrome (IBS).
  • The beneficial effects of probiotics on both gut and brain health help to solidify the important role that these two systems have on one another.

You’re probably already familiar with the brain-gut connection if you’ve ever experienced “gut feelings.” When thinking about brain health, it’s nearly impossible to separate it from what’s occurring inside your gut. In fact, these two systems are so similar that scientists have deemed the nerve cells of the digestive tract to be our “second brain.”

The mind-gut connection is so powerful that when one of these seemingly distinct organs is imbalanced, it can send the other into a state of distress. Perhaps one of the clearest examples of this is irritable bowel syndrome (IBS), which is known to be highly influenced by chronic stress. Even more, neurological and cognitive concerns like brain fog and memory loss, as well as mood disorders, are all thought to be associated with an unhealthy gut. 

When we look at these systems as two pieces of the same puzzle, we can begin to more effectively treat dysfunction in the brain by targeting dysregulation in the gut. Balancing the gut microbiome and reducing inflammation in the digestive tract are often highly beneficial for treating neurological and psychological symptoms and disease. 

Exploring the Mind-Gut Connection 

The digestive system and the brain are connected to each other through a highly intricate network of neurons (primarily the vagus nerve), which transmit signals from the GI tract to the brain and vice versa. 

Chemical messengers — known as neurotransmitters — are made in the gut and travel along the vagus nerve to the brain. When they reach the central nervous system, these neurotransmitters have a strong influence on our mood, appetite, memory, and even pain perception [1, 2].

The complex community of microorganisms that live in our gut is known as “the gut microbiome” and it plays a highly influential role in our overall health. When these trillions of tiny organisms are out of balance, they can lead to inflammation in our digestive tract and cause dysregulation of the gut-brain axis [3, 4].

Research now recognizes that when the gut ecosystem becomes imbalanced, otherwise known as dysbiosis, it also can alter brain function by producing inflammation in the brain [3, 4, 5, 6, 7]. Inflammation in the brain is one of the main drivers behind many neurological symptoms and conditions, one of which most of us have experienced from time-to-time: brain fog.

Breaking Down Brain Fog

Brain fog is an exceedingly common symptom that’s marked by cloudy thinking, poor mental stamina and mental fatigue, an inability to focus, and forgetfulness [8]. Neuroinflammation (inflammation in the brain) appears to be a significant underlying factor, and even one of the primary causes, for brain fog [9, 10, 11]. As we already know that inflammation in the gut can create neuroinflammation, it’s really not a surprise that the following digestive conditions are associated with chronic brain fog:

  • Irritable bowel syndrome (IBS) [12]
  • Small intestinal bacterial overgrowth (SIBO) [12, 13]
  • Inflammatory bowel disease (IBD), including Crohn’s disease [14]
  • Celiac disease and non-celiac gluten sensitivity (NCGS) [15, 16, 17]

Even chronic health conditions that are typically associated with significant brain fog, like chronic fatigue syndrome, fibromyalgia, and hypothyroidism, are all thought to have some sort of underlying imbalance in the gut. 

Many of these conditions that can affect our brain function appear to have a similar underlying factor — an unhealthy gut. However, as a quick mention, if you have any neurological complaints like brain fog, headaches, and mood disorders, you may have an imbalanced gut even if you aren’t having any digestive issues.

Harman’s Story

When Harman first arrived at the clinic she had been experiencing severe brain fog for years. It had begun to affect her work performance to the point where she was concerned about losing her job, and she started to experience symptoms of depression. She had seen seven other practitioners for her brain fog, but found no improvements.

She was aware of the gut-mind connection and was also combating several food sensitivities that she believed to be linked to her brain fog. In an attempt to resolve her symptoms she was on an extremely restrictive diet, consisting of just chicken and carrots. 

In just four months after starting treatment, which focused on expanding her dietary options and treating an underlying gut dysbiosis with probiotics and antimicrobials, her brain fog and food sensitivities were completely gone. 

Harman’s case not only highlights the significance of focusing on the gut when treating brain fog, but shows that this doesn’t have to be in a way that severely restricts your diet and compromises your quality of life.

The Brain’s Influence on the Gut: IBS

Now that we’ve explored the role that the gastrointestinal tract plays in our brain health, let’s take a look at how the brain affects our digestive health. While the gastrointestinal tract has its own nervous system, known as the enteric nervous system (ENS), the central nervous system also plays a leading role in digestion. 

The brain helps control digestion by regulating gastric motility, or the waves of muscular contractions that move food along the GI tract. Because of the brain’s direct influence on digestion, certain stimuli, like stress, can have a significant impact on our gut health. 

Changes in the gut-brain communication are thought to lie behind irritable bowel syndrome (IBS), and low levels of the neurotransmitter serotonin can affect digestive motility, increase the perception of pain, and alter mood in those with IBS [18, 19]. In fact, those with IBS are three times more likely to experience anxiety and depression [20].

Stress is well-known to be a common trigger for IBS symptoms, which frequently include:

  • Gas and bloating
  • Diarrhea
  • Constipation
  • Abdominal pain

Interventions that focus on stress reduction and restoring the gut-brain axis have shown to be highly effective in mitigating symptoms, reducing anxiety and depression, and improving overall quality of life in those with IBS [21].

Cognitive behavioral therapy (CBT), hypnotherapy, yoga, and meditation all work to alleviate stress and restore a normal response in the nervous system. They’ve shown to be highly beneficial for those with IBS, further solidifying the gut-mind connection [22, 23, 24, 25, 26, 27].

Probiotics for Better Brain Health

There’s perhaps no other supplement that better exemplifies the tightly interwoven mind-gut connection than probiotics. 

The relationship between probiotics and the nervous system is well-documented, and probiotics can be effectively used to treat anxiety, depression, brain fog, headaches, and a wide spectrum of neurological conditions. 

Probiotics work to rebalance the gut microbiota, which helps heal the gut-brain axis [28]. They also assist in restoring optimal gut health by:

  • Increasing the diversity of the gut microbiota (live bacteria in the GI tract) [28]
  • Fighting off pathogens (harmful gut microbes) and the toxins that they produce
  • Supporting a healthy immune system and response in the gut [29, 30]
  • Reducing damage to the gut lining, also known as leaky gut syndrome [31, 32, 33]

The above benefits of probiotics make it a standout supplement when it comes to treating neurological conditions. In one research study, those with multiple sclerosis (MS) who took a probiotic supplement for 12 weeks had less inflammatory markers and disability over those who took the placebo [34].

Probiotics for Cognitive Impairment

Research shows that probiotics are beneficial for improving cognitive function, likely by reducing inflammation, which, remember, is the main driver of brain fog [35, 36, 37, 38, 39, 40]. In healthy adults, probiotics changed the balance of gut bacteria, and improved cognitive function and mood [35].

However, the beneficial effects of probiotics on enhancing cognitive function appear to be higher in those who are already dealing with cognitive decline or dementia [41, 42].

Probiotics may be particularly helpful for those who experience cognitive decline or cognitive dysfunction, such as those who have Alzheimer’s disease, bipolar disorder, and fibromyalgia [36, 37, 38, 43].

Probiotics for Mental Health

When the gut becomes inflamed due to various factors, it breaks down the barrier lining the GI tract and allows for certain foreign bodies and toxic substances to slip through and enter the bloodstream (otherwise known as leaky gut). When these toxic substances reach the brain, they’re thought to contribute to mental health conditions like anxiety-spectrum disorders and depression [44, 45].

Probiotics help reverse this process and repair the lining of the gut, partially explaining the profound effect that they can have on regulating mood [31, 32, 33].

Furthermore, when the digestive tract isn’t healthy, it disrupts the normal flow of neurotransmitters to the brain, including serotonin, dopamine, and gamma aminobutyric acid (GABA), which likely contributes to various mood disorders. By healing the GI tract, probiotics can help restore the normal flow of communication from the gut to the brain.

There’s a strong body of research that shows probiotics to be significantly helpful in reducing symptoms of depression, particularly in those struggling with major depressive disorder [46, 47, 48, 49, 50]. 

One study found that multiple strains of probiotics were more effective in treating depression [49], which is why we recommend a triple probiotic therapy that utilizes strains from three different categories of probiotics. 

Probiotics may also be beneficial in reducing symptoms of anxiety, though the evidence isn’t quite as strong [51, 52, 53, 54, 55, 56]. In one well-designed clinical trial, 12 weeks of probiotic use lowered stress and anxiety symptoms in a group of highly stressed adults. Even more, they benefited from improvements in memory, social cognition, and verbal learning [57].

As probiotics are highly effective at healing the gut and reducing inflammation, it makes them an attractive therapy for healing the mind-gut connection and bringing you back to optimal health. Furthermore they’re safe, easy to use, and certainly don’t have to be expensive. 

Healing the Mind-Gut Connection

The gut plays an important role in regulating our cognition and mood, and has a strong influence on our brain health. An imbalanced gut microbiome and inflammation in the gut can be the driving force behind several neurological symptoms and conditions. 

The brain also plays an important role in the brain-gut axis, as it helps regulate digestion. Stress can easily disrupt this two-way street of communication, and its effects are most notable in those dealing with IBS. 

The beneficial effects of probiotics on the gut and the brain further bolster the role that these two organ systems have on each other, and are a highly effective therapeutic for treating various digestive and neurological conditions. For more information on the gut-brain axis, check out my book, Healthy Gut, Healthy You. 

You can also reach out to our clinic at the Ruscio Institute for Functional Health for help with healing your gut and brain, and restoring your overall well-being. 

The Ruscio Institute has developed a range of high-quality formulations to help our patients and audience. If you’re interested in learning more about these products, please click here. Note that there are many other options available, and we encourage you to research which products may be right for you.

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