What Is the Microbiome & How to Improve It

February 8, 2024
Gut microbiome

The human body is a complex ecosystem, housing trillions of microorganisms that make up the gut microbiome. This intricate network of bacteria, viruses, fungi, and other microbes plays a crucial role in maintaining our overall health and well-being. From supporting the immune system to aiding in digestion and nutrient absorption, the microbiome is a powerful force within us.

A healthy gut contains diverse populations of bacteria. Its composition is unique to you. Your diet, who you touch, whether you have pets, illnesses, age, genetic factors, smoking, alcohol use, where you live, and birth method (vaginal or c-section) can all affect your microbiome.

Researchers are working to better answer the question, “What is the microbiome?” Learn more about your microbiome and how your choices affect it, which, in turn, affects your overall health.

What is the Microbiome?

At its core, the microbiome refers to the diverse collection of microorganisms that inhabit our body, particularly the gut. These microorganisms include bacteria, viruses, fungi, and archaea. Researchers estimate that an average-sized person is made up of 3.8 x 1013 bacteria and 3.0 x 1013 human cells.1 Close to 3,000 bacterial species have been identified in human stool.2

The gut is the entire digestive system. Each area of the gut has its own microbiome. The conditions in these mini-microbiomes can vary. For example, microorganisms may need to withstand the extreme acidity in the stomach.2

Most of the microbes living in your gut live in the cecum. This is a large outpouching of the large intestine. The cecum is an ideal environment for microbes to inhabit because it:

  • Is spacious and less mobile than other parts of the gut
  • Is rich in undigested fibers and complex carbohydrates
  • Allows for a close relationship between gut bacteria and immune cells in the wall of the cecum

What is the microbiome? Although the term microbiome is often used interchangeably with microbiota, it is important to note the distinction. The microbiota refers to the actual microorganisms, while the microbiome encompasses their collective genomes and the interactions between them.

A graphic of gut bacteria answering the question: what is the microbiome?

The Role of the Microbiome

The microbiome influences various aspects of our well-being, including immune function, digestion, metabolism, and even mental health. The microbiome acts as a symbiotic partner with its human host. Gut microbiota are essential for human health, and the human gut provides a hospitable environment for the microbiome.

The Gut Microbiota and Immune Function

Gut microbes play a crucial role in shaping and modulating the immune system. Gut microbes teach your immune system how to react to pathogens. They help immune cells distinguish between harmful pathogens and harmless substances or beneficial bacteria.

The gut microbiome contributes to maintaining a healthy gut lining. They help keep harmful bacteria and other pathogens from crossing the gut lining and entering the bloodstream.

Gut microbiotas produce chemicals such as short-chain fatty acids that can directly influence immune function. Short-chain fatty acids have anti-inflammatory properties that can help keep the immune response in check.

Inflammation and Diseases

Imbalances in the gut microbiota can lead to dysregulation of the immune system, resulting in chronic inflammation. This inflammation has been linked to various diseases, including autoimmune conditions, allergies, type 2 diabetes, psoriasis, obesity, cardiovascular disease, autism spectrum disorder, and others.2,3

Influencing Your Dietary Choices

The microbiome is also crucial to determining your dietary choices. Your senses of sight, smell, texture, and taste help you choose which foods to consume. Once you consume the food, the gut will determine its nutritional value. Sensory cells, called neuropod cells, transmit impulses up the vagus nerve to your brain. You will seek out more of these foods, especially sweet foods. Researchers have found that even if you bypass the sense of taste, animals and humans will seek out sweet foods.4

Influencing Your Mood

The gut releases chemicals that influence brain function, including mood. Research suggests that gut microbiomes in people living with depression, anxiety, and bipolar disorder are more likely to have higher levels of bacteria that increase inflammation and lower levels of protective bacteria.5

A woman with stomach pain

Improving your Microbiome

Since many factors influence your microbiome, you may be able to improve your gut health and diversity.

Enhancing the Microbiome Through Diet

Diet plays a significant role in shaping the composition of the gut microbiome. Consuming a diet rich in fiber, fruits, vegetables, and whole grains provides nourishment for beneficial microbes. These foods are known as prebiotics, as they serve as fuel for the growth of healthy bacteria in the gut.3

Gut bacteria ferment prebiotics and generate molecules such as short-chain fatty acids. These molecules supply the gut lining with nutrition, lower gut acidity, reduce inflammation, elongate the microvilli lining the gut, and protect the gut from pathogens.

Incorporating fermented foods, such as plain yogurt, kefir, sauerkraut, and kimchi, can also introduce beneficial bacteria into the gut as long as they contain live active cultures. In one study, researchers found that a diet rich in fermented foods increases microbiota diversity and decreases inflammation.7

Probiotics and the Microbiome

Probiotics, which are live bacteria and yeasts, can be a valuable tool in promoting a healthy microbiome. Probiotics are thought to reduce intestinal permeability, decrease gut acidity, protect against pathogens, and improve immune function.3

Probiotics can increase beneficial bacteria and assist in digesting and absorbing food nutrients. However, the response, if any, is individualized.

Antibiotics can disrupt the microbiome. Probiotics can help restore a healthy microbiome after taking antibiotics.8 Probiotics may also be helpful to restore the microbiome after an infection.

It is important to recognize that the U.S. Food and Drug Administration does not regulate probiotics. The microbe concentration in probiotics can vary. Probiotic effectiveness can vary from person to person. Look for supplements carrying the U.S. Pharmacopeial (USP) Convention seal.

Stress Management

Chronic stress can disrupt the delicate balance of the gut microbiome. High levels of stress hormones, such as cortisol, have been shown to increase gut permeability, leading to inflammation and imbalances in the microbiota.

Implementing stress management techniques, such as meditation, exercise, and adequate sleep, can help support a healthy microbiome.

Physical Activity

Regular physical activity has been associated with a more diverse and resilient microbiome. Exercise promotes gut motility, which aids in eliminating waste and promoting a healthy digestive system. Engaging in activities such as walking, jogging, or yoga can positively impact the composition of the gut microbiome.

Maintaining a healthy microbiome is a lifelong journey. By prioritizing a diet rich in prebiotic foods, consuming fermented foods, reducing sugar intake, incorporating probiotics when appropriate, managing stress levels, and engaging in regular physical activity, you can foster a thriving microbiome that supports your overall health.

The gut produces the hormone GLP-1. The microbiome impacts GLP-1 hormone production. Research suggests that the microbiome impacts your risk for weight gain and obesity. Medications such as the semaglutide supplement GLP-1 reduce appetite and food cravings and lead to significant weight loss. If you have questions about semaglutide, contact a treatment specialist at Invigor Medical.

Get started today with a subscription for Semaglutide.

Author: Leann Poston, M.D.
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