The gut microbiome, a bustling community of trillions of microorganisms residing primarily in our large intestine, is often overlooked in its pivotal role in our overall health. Comprising an estimated thousands of different species, this complex system holds the potential to greatly impact many facets of our well-being, earning it the moniker "the forgotten organ". While the gut microbiome is obviously important for digestion and metabolism, it controls and regulates a number of bodily functions, and is key in preventing disease.

What is the Gut Microbiome?  

The gut microbiome refers to the complex community of microorganisms, including bacteria, fungi, viruses, and other microbes, that reside in the gastrointestinal tract, primarily in the large intestine. It is estimated that there are trillions of microbes and thousands of different species in the gut microbiome. It plays a crucial role in maintaining human health and is often referred to as a "forgotten organ" due to its numerous functions and impact on various aspects of our well-being.  The gut microbiome is composed of a mixture of beneficial and potentially harmful microorganisms. Many of these microorganisms have a symbiotic relationship with the human body, which benefits both parties. There are also a smaller number of pathogenic microorganisms that can cause disease. In a healthy individual, the pathogenic and symbiotic microorganisms coexist harmoniously.  

The Importance of the Gut Microbiome

The gut microbiome plays a role in the following important areas:

1. Immune Development and Regulation: The gut microbiome plays a crucial role in the development and regulation of the immune system, particularly during early life. Exposure to a diverse range of microorganisms in infancy helps train and shape the immune system, influencing its responses later in life.
2. Gut Barrier Function: The gut microbiome contributes to maintaining the integrity and function of the intestinal barrier, which acts as a physical barrier against pathogens and harmful substances. A healthy gut microbiome promotes a stronger barrier, preventing the entry of harmful microorganisms and reducing the risk of systemic infections and inflammation.
3. Immune Tolerance and Autoimmunity: The gut microbiome is involved in immune tolerance, the ability of the immune system to distinguish between harmful pathogens and harmless substances. Imbalances in the gut microbiome can disrupt immune tolerance and contribute to the development of autoimmune diseases, where the immune system mistakenly attacks the body's own tissues.
4. Inflammatory Response: The gut microbiome can influence the immune system's inflammatory response. Dysbiosis in the gut microbiome, has been associated with chronic low-grade inflammation, which may contribute to the development of inflammatory conditions such as inflammatory bowel disease, rheumatoid arthritis, and metabolic disorders.
5. The Gut-Brain Axis: The gut-brain axis is an intricate and bidirectional communication network that connects the gastrointestinal tract with the brain. This complex system involves a constant exchange of signals and information between the gut and the brain, influencing various aspects of our physical and mental well-being. It encompasses neural, hormonal, and immunological pathways that allow for seamless communication and interaction between these two vital systems.  

The Connection Between the Gut Microbiome and Disease

Depression and Mental Illness

The gut microbiome can influence neurotransmitter production, stress responses, and mood regulation. In fact, the microbiome produces 85% of the body’s serotonin, a neurotransmitter that regulates mood. Disruptions in the gut microbiome have been associated with conditions like depression, anxiety, and neurodevelopmental disorders.   Studies have found that individuals with depression often exhibit lower gut microbiota diversity, meaning a reduced number of different microbial species. Decreased microbial diversity has been associated with various mental health conditions, including depression. A limited clinical trial published in the Journal of American Medicine – Psychiatry revealed a drop in depression and anxiety scores after a treatment course of probiotics. While this research is directional, it does show the connection between gut microbiota and the expression of mental health.

Heart Disease

Numerous research studies have illustrated the link between the gut microbiome and heart disease.  One such study reveals that gut microbiota can produce trimethylamine-N-oxide (TMAO), a metabolite linked to arterial stiffness and coronary artery disease. This production is triggered by certain foods, like beef, pork and eggs.  Researchers have also used gene sequencing to identify specific gut bacteria that are highly correlated with atherosclerosis, a hardening of the arteries that puts patients at high risk for heart attack.   The findings from this research highlight the potential therapeutic strategies targeting gut microbiota and its metabolites for preventing cardiovascular disease.

COVID

Though COVID-19 primarily affects the respiratory system, research has suggested that the gut microbiota may also play a role in the disease. Patients with COVID-19 may experience a range of symptoms affecting the gastrointestinal system, like nausea, vomiting, diarrhea, and abdominal pain. The COVID virus has been found in the feces of people with the disease, indicating the presence of a “gut-lung axis”, a direct link between digestive and pulmonary systems.  Some studies have found alterations in the gut microbiota composition of COVID-19 patients, with a decrease in beneficial bacteria and an increase in harmful bacteria. These changes may contribute to the severity of the disease and the development of complications.  

Keeping a Healthy Gut Microbiome

A healthy microbiome is associated with the presence or abundance of certain biomarkers and bacteria, and the lack of others. Further, gut microorganisms often produce compounds that are either healthy or detrimental to the body, and these compounds are balanced in a health gut.  

Eat Plenty of Fiber

One such compound produced in the gut is short chain fatty acids, which are by products of fiber fermentation in the digestive system. SCFA regulate the body’s immunity against cancer, inflammation, obesity and other conditions. In order to reap these benefits, it is recommended that adult women eat 21-25 grams and men eat 30-38 grams of fiber per day. This goal can be achieved through a combination of whole grains, beans and legumes, and leafy green vegetables.

Consider Probiotics and Prebiotics

Probiotics, also known as "good bacteria," play a vital role in restoring the natural balance of bacteria in the gut. When our gut microbiome is disrupted by factors like an unhealthy diet, stress, or the use of antibiotics, it can lead to various health issues. Probiotics work by replenishing the gut with beneficial bacteria, boosting the body's natural immune responses, and improving digestive function. You can find probiotics in supplements, in yogurt, and in fermented foods like sauerkraut and pickles. Prebiotics are a type of dietary fiber that act as a food source for the beneficial bacteria in our gut. Unlike other fibers, prebiotics are not digested in the upper gastrointestinal tract and reach the colon relatively intact. There, they are fermented by the gut microbiota and promote growth and activity of beneficial bacteria. Common foods that are high in prebiotics include whole grains, bananas, greens, onions, garlic, soybeans, and artichokes. Fountain Life utilizes gut microbiome testing and analysis as a component of our holistic approach to diagnosing and treating serious illness. If you would like to find out more about our programs, click here for a Program Advisor who can tell you more.