Dysbiosis and the Microbiome

To begin to understand gut dysbiosis, we must first review the gut microbiome. A microbiome is a collection of microbial organisms such as bacteria, fungi, and viruses that all live together in a specific environment. In this case, we are talking about the community of microorganisms that typically inhabit the human gut. One of the many functions of the gut microbiome is to help us humans digest our food properly and efficiently so that we can reap all the benefits it has to offer.

Dysbiosis occurs when our naturally healthy and diverse microbial composition is thrown out of balance. This can happen for a wide variety of reasons, a few common ones are changes in diet, stress, food sensitivities, environmental exposures, and so many others. Chronic gut dysbiosis is associated with a number of not so pleasant health effects, from bloating, inconsistent bowel movements, and abdominal pain to lowered immune function and possibly even conditions like irritable bowel syndrome, type II diabetes, Parkinson’s disease, cancer, Crohn’s disease, and small intestinal bacteria overgrowth (SIBO). Our gut health has impacts on nearly all other parts of the body, including the skin, the lungs, and especially the brain. (The potent effect that our gut health has on our mental health is a fascinating topic for another time.)

What causes dysbiosis?

According to Wegierska et al., there are five main causes of dysbiosis:

1. Deficiency of beneficial microbial populations due to underconsumption of soluble dietary fiber or antibiotic use

2. Petrification caused by a diet high in animal products and low in fiber

3. Fermentation caused by intolerance to certain carbohydrates or over consumption of simple sugars

4. Sensitization of the immune system to some microbial component in the gut

5. Fungal dysbiosis, which is generally caused by overconsumption of simple sugars, bread products, and low fiber intake

There are many environmental and host-related factors that may also play a role in the development of dysbiosis such as living environment, tobacco exposure, alcohol use, stress, and exercise.

So, what can we do to avoid gut dysbiosis?

As they say… prevention is the best medicine.

Nutritionally supporting your body’s microflora is one of the best ways to avoid gut dysbiosis. What does this look like? On the simplest level, this looks like eating a diet high in whole foods, many of those being plants, and containing adequate amounts of fiber. Dietary fiber comes in multiple forms; soluble and insoluble. Soluble fiber comes from the inner fleshy part of a fruit, veggie, or grain. As its name suggests, it is water soluble and it is transformed into a gel-like substance in the colon which acts a food source for your beneficial gut microbes, you may hear this type of fiber referred to a prebiotic. Insoluble fiber on the other hand comes from the outer skin of a plant food and is eliminated from the body rather than digested. Both types of fiber are important for supporting optimal gut health in their own ways, and most people are not eating enough of them. Including lots of healthy fruits, vegetables, nuts, seeds and grains (as long as they are well tolerated) is the best way to maintain a happy gut.

Mental and physical health also play an important role in gastrointestinal health. Growing evidence tells us that exercise has a positive impact on gut health and brain health, and we know that both of these biological pathways are bidirectional. In fact, the gut-brain connection is so strong that the gut is often referred to as a “second brain”. Thus, it is important to consider our mental, emotional, and physical health when we are talking about the gut and its microbiome.

References:

1. Manos J. The human microbiome in disease and pathology. APMIS Acta Pathol Microbiol Immunol Scand. 2022;130(12):690-705. doi:10.1111/apm.13225

2. Wegierska AE, Charitos IA, Topi S, Potenza MA, Montagnani M, Santacroce L. The Connection Between Physical Exercise and Gut Microbiota: Implications for Competitive Sports Athletes. Sports Med Auckl Nz. 2022;52(10):2355-2369. doi:10.1007/s40279-022-01696-x

3. Yusuf K, Saha S, Umar S. Health Benefits of Dietary Fiber for the Management of Inflammatory Bowel Disease. Biomedicines. 2022;10(6):1242. doi:10.3390/biomedicines10061242

4. Exercise, diet and stress as modulators of gut microbiota_ Implications for neurodegenerative diseases | Elsevier Enhanced Reader. doi:10.1016/j.nbd.2019.104621