Here Are All the Why’s and How’s of Building a Healthy Gut Microbiota

This post was contributed by special guest author and nutritionist, Anna Redmayne-Porter. You can find more of her inspiring content—including gut-supporting recipes—on her Instagram feed.

Over the last year there has been a lot of buzz in the media surrounding gut health—with the mysterious microbiome being at the center of that attention. If the headlines about the microbiome have caught your attention, you’re probably wondering, “What is all the fuss about?”

An Introduction to the Microbiome

The human microbiome refers to the collective genetic material of the microorganisms living both on and in our bodies. Experts refer to the human microbiome as an organ in its own right. An individual’s microbiome is composed of a staggering 10–100 trillion microbial cells!

More specifically, a microbiota is the aggregate of microorganisms—including bacteria, fungi and viruses—that reside in a particular location. Areas of the body that are colonized by microorganisms (therefore becoming microbiota) include, but are not limited to, our skin, oral cavity, lungs and, most famously, our gut.

The Importance of a Healthy Gut Microbiota

A gut microbiota—or “gut flora”—that’s considered healthy is one that’s stable and high in beneficial microorganisms. It’s crucial to maintain this state due to the gut’s responsibility of carrying out a range of jobs which support the human body, including the synthesis of nutrients and energy through fermenting non-digestible foods (which helps us fully utilise the food we eat) and the support of the immune system by defending the body against pathogens. Additionally, research suggests that a healthy gut can prevent gut dysbiosis—an imbalance of microorganisms in the gut—which may be related to mental illnesses such as depression and anxiety.

Even skin health can be impacted the by state of the gut, and the importance of a healthy gut microbiota is currently being explored in relation to preventing and treating allergic diseases such as atopic dermatitis (a type of eczema). A recent study of pregnant women and breastfeeding mothers assessed how taking a probiotic supplement for an extended period of time might impact the skin health of the infants; the results show that the prevalence of eczema seen in the infants at the one-year mark was significantly lower in those exposed to probiotic supplementation than those in the placebo group.

In brief, the list of benefits of hosting a healthy gut microbiota is extensive and, put simply, without it we would be unable to function optimally. But it’s also important to note that gut health exists in a delicate balance and there are a number of ways you can both support and disrupt the gut’s natural rhythms.

What Supports a Healthy Microbiota? What Disrupts It?

A healthy gut flora is established during infancy. When an infant is born, its gastrointestinal tract—the organ system responsible for digesting and absorbing nutrients from food—is immediately colonised by microbes (microorganisms). Research suggests that by age one, an infant’s gut microbiota begins to resemble that of an adult as a result of the continuous interaction between the microbiota and the environment. (Note: Some emerging research even suggests that the infant gut could be colonised in utero.)

Gut flora can be impaired after using antibiotics, by experiencing excessive and chronic stress, and by not getting enough sleep or physical activity. It can also be damaged by excessive alcohol consumption. In a study that compared the guts of alcoholics to those of individuals who consume little or no alcohol, “Dysbiosis was present in 27% of the alcoholic population, but it was not present in any of the healthy individuals.”

Additionally, as we age, we may experience a decline in the stability of the gut microbiota due to weakened immune functioning. However the data on gut microbiota and aging suggests that what we eat has the biggest impact on gut health, and that “in the elderly, microbial diversity and composition is primarily driven by dietary factors.” Relatedly, an unhealthy gut microbiota has been linked to obesity; findings from a 2013 study show the obese participants as having lower “bacterial richness” than those who maintained a regular body mass index.

What to Eat for a Healthy Gut Microbiota

With diet being the most important determinant of adult gut microbiota composition, even short-term dietary changes can have a significant impact on its makeup.

Diets high in sugar, artificial sweeteners, food additives and meat products are associated with an unhealthy gut microbiota; results from a recent study show that participants who consumed a diet high in animal products were more likely to host an overgrowth of microorganisms capable of triggering inflammatory bowel disease. Inversely, some studies suggest that well-rounded, plant-based diets are linked to a diverse and healthy gut microbiota.

Even if you’re not able or willing to commit to a primarily plant-based diet at this time, you can still support your gut by focusing on consuming an adequate amount of naturally sourced fiber (as it’s found in fruits and vegetables) and by supplementing with high-quality probiotics. Experts define probiotics as “live microorganisms administered in adequate amounts that confer a health effect on the host.” They’re also commonly referred to as “friendly” bacteria that possess the power to restore and balance bacteria in the gut microbiota.

Foods high in probiotics include fermented products like yogurt, sauerkraut, tempeh, kimchi, miso, kombucha, apple cider vinegar and natto. These products might not be on your weekly shopping list, but they are well worth testing out due to their spectacular probiotic content.

Relatedly, when shopping, check food labels for the following friendly bacteria:

  • Lactobacillus acidophilus
  • Lactobacillus bulgarius
  • Lactobacillus reuteri
  • Streptococcus thermophilus
  • Saccharomyces boulardii
  • Bifidobacterium bifidum
  • Bacillus subtilis

Similarly, prebiotics have been shown to support gut health. Prebiotics are the non-digestible fiber that probiotics feed off. Examples of foods rich in prebiotics include raw or cooked onions, raw asparagus and leeks, bananas, artichokes, and chicory root. These will give your gut microbiota an extra boost of vitality.

Love Your Gut

Taking care of your gut microbiota is imperative as it serves many important health functions. The smallest of changes can upset its balance and have detrimental effects on the body. Following a mainly plant-based diet and avoiding sugar, artificial sweeteners and food additives where possible can go a long way toward building a healthy gut microbiota. If you want to go the extra mile, add some probiotics and prebiotics to your diet—these will give your gut a helping hand.