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Gut Health

Role of the Gut-Brain Axis and Your Health

Role of the Gut-Brain Axis and Your Health

The gut plays an essential role in maintaining your good health by influencing the behavior of several body systems.

The gut is vital for the daily regulation of key functions in the digestive, immune, and endocrine systems. However, one of the most significant modulatory roles the gut performs in the body is maintaining communication with the brain.

The connection is known as the gut-brain axis and is crucial in maintaining good brain health. This includes mood stability, memory capacity, body clock regulation, and promotes whole-body health.

What is Gut-Brain Axis?

The gut-brain axis is a complex communication network that connects your brain and gut via the central (CNS) and enteric (ENS) nervous systems.

This bidirectional communication relay between the brain and intestinal ecosystem is maintained through both physical and biochemical means, playing a role in almost all physiological functions within the body.

Messages from the brain to the gut can influence the composition of the gut and microbiome by stimulating changes in your eating habits and nutrition absorption in the intestines. Subsequently, the brain can also affect how your weight is maintained.

Additionally, the communication from the gut can impact function of the brain. Including increases or decreases in hormones that can affect levels of stress, depression, and anxiety.  

The Microbiome’s Role in the Gut-Brain Connection

The microbiome is thought of as the singularly most important component of the gut-brain axis.

Often referred to as the “second brain,” the gut microbiome plays an essential modulation role in regulating bidirectional communication and daily brain function.

The thousands of diverse microbes in the gut produce a variety of chemicals that play an essential biochemical modulation role over many body systems. Including the ENS, CNS, neuroendocrine system, which are all vital in maintaining whole-body health via the gut-brain axis.

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How the Gut-Brain Axis Works

There are three main avenues that the gut and brain use to maintain their bidirectional communication and mutual influence. Including 1) the Vagus nerve, 2) neurotransmitters, and 3) microbial metabolites.

Vagus nerve and neurons

The Vagus Nerve and neurons are two essential neurological modulators of the gut-brain axis.

Neurons are cells of the nervous system, both found in the CNS and gut, whose signals influence body behavior. These cells also assist activation of the Vagus nerve, the main connector between the gut and brain.

Bidirectional communication via the Vagus nerve stimulates activates from fat storage and inflammation in the gut to stress-effects on the brain.


Neurotransmitters are produced by both the brain and digestive system and maintain the chemical connection between the gut and brain.

Neurotransmitters produced in the brain contribute to mood and body clock stabilization, including serotonin and cortisol.

The gut microbiota produce similar chemicals that stabilize functions of the brain, including serotonin. It also produces gamma-aminobutyric acid (GABA), which is an important neurotransmitter for regulating feelings of anxiety and fear.

Other microbial chemicals

Beyond neurotransmitters, gut microbes produce other key metabolites that influence functions of gut-brain communication.

This includes short-chain fatty acids, like butyrate, propionate and acetate, released during dietary fiber digestion. These acids are involved in functions such as appetite suppression as well as fortification of the blood-brain barrier.

Health Benefits of a Strong Gut-Brain Connection

Improved brain function

A strong gut-brain connection ensures effective and efficient bidirectional communication.

A more efficient relay along the gut-brain axis can improve a wide host of functions within the emotional and cognitive centers of the brain connected to peripheral intestinal function.

This includes sharper memory and learning skills, ability to focus, and improved sleep quality.

Mood stability

Because intestinal function plays a key role in the emotional center of the brain, a fortified gut-brain axis can assist with stabilizing mood. Also, neurological disorders associated with low levels of mood stabilizing neurotransmitters.

For example, individuals suffering from neurological dysfunction found in depressive disorders, lack a sufficient amount of serotonin, produced by bacteria Bifidobacterium and Lactobacillus, the gut that is delivered to the brain.

Reduced inflammation

The gut-brain axis also has an important connection through the immune system.

A strong gut and microbiome, high in the anti-inflammatory bacteria Faecalibacterium, can enhance immune system efficiency and reduce chronic inflammation. Inflammation can weaken the bidirectional relay and promote neurological disorders, including depression, Alzheimer’s, and Autism.

Reduced gut permeability

A sound gut-brain axis can also benefit the strength of the intestinal wall. Prolonged stress is known to be a key promoter of increased intestinal permeability, also known a ‘leaky gut,’ via chronic inflammation in the digestive system.

Protection of the intestinal walls reduces risk of dysbiosis, bacterial endotoxin seepage from the gut, and production of neuroactive metabolites in the gut. These harmful chemicals play a role in the development of several neurological disorders associated with leaky gut, including autism and schizophrenia.

How Your Gut-Brain Axis Can Be Altered

A negative change in your gut-brain axis can lower the gut and brain’s ability to communicate. This can give rise to a variety of poor health outcomes, including suppressed immune function, neurological dysfunction, and increased risk of leaky gut development.

The most common cause of alteration of the gut-brain axis is dysbiosis. Unfavorable changes in the gut microbiome can occur from a variety of controllable and uncontrollable causes. Such as poor diet and sleep habits as well as infection, digestive distress, and gastrointestinal disorders.

How Can You Improve Your Health and Gut-Brain Connection?

A balanced diet that fortifies the gut microbiota has been recognized as a key factor in improving your gut-brain connection and overall health.

Foods that enhance the health of your microbiome and gut-brain axis you will want to prioritize in your diet include prebiotic and probiotic foods.

Prebiotic foods contain fibers that boost growth of microbiota by feeding good gut microbes, like bacteria. ‘High-fiber foods’ whole wheat products, berries, and beans. Prebiotic supplements are also beneficial if your diet is lacking in fiber-rich foods.

Additionally, probiotics contain live strains of beneficial bacteria that can add to your gut microbiome to improve diversity and strength. Foods known to be highest in probiotics are fermented foods, like yogurt, kimchi, and tempeh.

If your diet is lacking in probiotic foods, quality supplements, like BIOHM's are recommended. Also, search for a probiotic supplement that contains strains of Bifidobacterium, Lactobacillus, and the yeast Saccharomyces, which are known to be most effective in improving gut-brain communication.

By prioritizing prebiotic and probiotic foods and high-quality supplements, This can help to keep your microbiome rich, diversified, and your gut-brain axis functioning efficiently for best whole-body health.


About the Authors:

Dr Mahmoud Ghannoum, Ph.D, EMBA, FAAM, FIDSA is widely considered the leading microbiome researcher in the world. He is the scientist who named the mycobiome, and is the founder of BIOHM, the first company to engineer products and tests to address the total microbiome of both bacteria and fungi, allowing consumers to maintain total digestive health. Ghannoum is responsible for making the breakthrough discovery that bad bacteria and bad fungus work together to create digestive plaque (a discovery covered globally by outlets such as CBS News, Scientific American, Forbes and USA Today). During his career, he has published several books on fungus and over 400 peer-reviewed scientific papers. His work has been cited almost 24,000 times by other scientists, and Stanford University named him as one of the top 0.1% of most cited scientists over the last decade.

Allison Lansman, RDN, LD is a freelance writer and owner of The Freelance RD Nutrition Writing Services. She is passionate about creating exciting, research-based nutrition blog posts with her professional background as a dietitian. Allie prioritizes creating articles all readers can understand and incorporate into their daily lives. 

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