The Gut Microbiome: How Does It Impact Your Health?

Published July 9th, 2020 by Dr. Kaylea Swearingen, PharmD
Fact Checked by
Chris Riley

When you hear the words “bacteria" or "virus," what are your first thoughts?  If you are anything like me, they probably make you think about the times you have been sick with a cold or the flu, which are not the most pleasant memories to think back on.

The truth is not all bacteria and viruses are harmful.  Your body is made up of trillions of microbes, and together they are known as the microbiome, which is very important for your health. 

What is the Gut Microbiome?

An individual can have up to five pounds of microbes living in their gut.  The majority of these microbes are found in the cecum, the pocket of the large intestine, and are known as the gut microbiome. Interestingly, two-thirds of the gut microbiome is unique to an individual.

The gut microbiome is made up of trillions of microbes with thousands of different species of bacteria.  We have more bacteria cells than human cells, about 40 trillion compared to 30 trillion.  The bacteria in the gut help with digestion, aid in the production of specific vitamins and influence our immune system.

The Development of the Gut Microbiome

Starting at birth and continuing throughout our lives, the gut microbiome is continually evolving.  You are first exposed to microbes at birth; however, there has been recent evidence suggesting babies are exposed to microbes while still in the womb.

As we grow, the gut microbiome diversifies to contain many types of microbial species.  More diverse gut bacteria are considered better for your health.  Remember that two-thirds of your gut microbiome is unique to you, and it is influenced by the food you eat, the air you breathe, and other environmental factors.

An imbalance of healthy and unhealthy microbes, gut dysbiosis, can contribute to the development of allergies or other conditions.  A recent study looked into the relationship between gut dysbiosis and allergies in adults. It showed that fecal microbiota richness, which is the number of species in the gut, was significantly lower in patients with allergies.  Patients with nut and seasonal allergies had the most significant imbalance.

What Does the Microbiome Have to Do with My Health?

There are many essential ways the gut microbiome impacts how your body functions and influences your health.

Fiber and Gut Health

Certain healthy bacteria in the gut digest fiber to produce short-chain fatty acids (SCFA).  Fiber may help prevent weight gain, diabetes, and impact heart health, which means the gut microbiome plays a role in these diseases.

SCFA are the primary source of fuel for the cells in the colon, but they may also reduce diarrhea and aid in the treatment of inflammatory bowel diseases (IBD).  Ulcerative colitis and Crohn’s disease are two types of IBD, and both have symptoms of chronic inflammation of the bowel.  SCFA, such as butyrate have been shown to have anti-inflammatory properties, which makes them beneficial in the symptom improvement in these diseases.

Bifidobacteria and Lactobacilli are healthy bacteria that help to fill in the gaps between intestinal cells, which can prevent the leaky gut syndrome.  They are also found in many probiotics or yogurt and can reduce symptoms of irritable bowel syndrome (IBS).

Weight Gain

There have been many studies looking into a connection between the gut microbiome and weight gain.  It is still unclear if there is a direct association, but the gut microbiome's health can be a contributing factor to weight gain.

The journal Open Forum Infectious Disease published a case report in 2015 about a woman who underwent fecal microbiota transplantation (FMT) using an overweight donor and unexpectedly gained weight after the procedure.  According to the authors, the woman was not obese before the procedure. While there could be other contributing factors to the weight gain, there is a possibility the weight gain was a consequence of the FMT donor being overweight.

How can You Improve Your Microbiome?

Here are a few of the many ways to improve your gut microbiome:

  • Eat a diverse range of food: the more diverse your gut bacteria, the better it is for your health, and diet can impact that bacteria
    • Vegetables, legumes, beans, and fruit are great options because they are high in fiber, which will promote the growth of beneficial bacteria such as Bifidobacteria in the gut.
    • Fermented foods like yogurt contain healthy bacteria such as lactobacilli
    • Whole grains also contain fiber, which will promote the growth of beneficial bacteria
  • Limit artificial sweetener intake: Artificial sweeteners have been shown to alter the gut microbiome's make-up, leading to increases in blood sugar
  • Breastfeed child for at least six months: Breastfeeding can promote the growth of the beneficial bacteria Bifidobacteria because that bacteria digests the sugars found in breastmilk 
  • Take a probiotic supplement: Probiotics may not impact healthy individuals' gut microbiome, but they can help restore it in those that are sick. Always check with your pharmacist or primary care physician first before starting any supplements as probiotics may not be appropriate for all individuals.

The bottom line

The gut microbiome contains trillions of microbes that play an essential role in your health.  If there is an imbalance in the healthy and unhealthy bacteria, it can potentially impact your weight and gut health. The key to a healthy gut microbiome is to eat a variety of fruits, vegetables, whole grains, and fermented foods. The more diverse your gut microbiome, the better it is for your health.

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Published July 9th, 2020 by Dr. Kaylea Swearingen, PharmD
Fact Checked by
Chris Riley

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