15 Nov What Is The Role Of The Gut Microbiome In Health And Disease?

People often stress the importance of diet, but the gut microbiome is often overlooked as people try to address health problems or freshen up healthcare routines. What is the role of gut microbiome in health and disease, and how can you get tested to find out more about your own?

What is the gut microbiome, and how does it impact health and disease?

The gut microbiome is a complex system of viruses, bacteria, fungi, and other living microorganisms that exist in your intestines. They are primarily located in the large intestine within a natural “pocket” known as the cecum and collectively weigh 2-5 pounds – similar to the human brain. There are a number of health aspects that the gut microbiome can affect.

Obesity

The connection between gut microbiome and obesity has gained much attention in recent years. Studies have revealed that the makeup of bacteria in the gut can influence whether a person is likely to gain weight.

A specific bacteria strain called Christensenellaceae minuta is more common in people with a low body weight. A study conducted by Cornell University and King’s College London researchers found that genes play a strong role in whether this bacterial strain is present in the gut.

Another study indicates that a lack of certain bacteria in the gut can lead to slowing brown fat activity, which slows the burning of calories and white fat.

A different study involves a woman who had a fecal microbiota transplantation procedure from an overweight donor, after which she became obese over a short period of time.

Depression

The gut microbiome plays an important role in mental health, producing 95% of the body’s supply of serotonin according to the American Psychological Association (APA).

A 2014 study indicates that prebiotics may help reduce stress and anxiety because they boost healthy bacteria in the gut. Those who received prebiotics in the study were more apathetic to negative stimuli, and had lower cortisol levels.

Autism

The connection between the gut microbiome and autism has been more closely examined in the past decade. Researchers in a 2013 study hypothesized that gut microbes alter metabolites associated with communication between the gut and brain. They found that children with autism had lower levels of three specific bacteria: Prevotella, Coprococcus, and Veillonellaceae.

In infants

The gut microbiome plays an essential role in infant development, impacting physical and neurocognitive function, as well as the risk of disease later in life. In general, the more diverse the gut microbiome is, the healthier it is.

However, infants are born with a much less diverse gut microbiome than adults. The first three years of life appear to be key in the development of the gut microbiome, and factors like mode of delivery, early use of antibiotics, and diet all influence the composition of the gut microbiome.

Cancer

Gut bacteria has been linked both to the development of cancer as well as playing a role in more effective cancer treatment. Lactobacillus johnsonii is a bacteria linked to the development of lymphoma; Helicobacter pylori may play a role in causing stomach cancer and duodenal ulcers by interfering in the regulation of inflammation. Other specific combinations of gut bacteria have been associated with colorectal cancer.

However, other studies indicate that a healthy gut microbiome enables immunotherapy, chemotherapy, and some anti-tumor drugs to work significantly better.

Human gut microbiome viewed across age and geography

Once a child reaches 3 years of age, their gut microbiome is usually similar to that of an adult. Environment, lifestyle, and diet all continue to strongly influence gut microbiome as you age. Later in life, changes in digestion, monotony in diet, and decreased nutrient absorption can cause a decrease in the gut microbiome’s diversity.

Gut microbiomes can be strongly impacted by lifestyle and cultural dietary choices. Multiple studies comparing the gut microbiomes of various cultures and ethnicities indicate their strengths and weaknesses often correlate with the diets consumed.

In other words, diets that emphasize proteins have more bacteria that facilitate the breakdown of proteins in their gut microbiomes; those who eat more carbohydrates have more bacteria related to the breakdown of carbohydrates. This offers both advantages and disadvantages to individuals; luckily, research indicates that a change in diet can restore balance to the gut microbiome.