“Gut health” is one of the biggest buzzwords in the wellness community. A quick visit to any holistic living blog or health influencer’s Instagram page will likely turn up several posts about this trendy topic. But what exactly does microbiome mean?

Tens of trillions of microbes, or bacteria, have been residing in our digestive system since the beginning of time. Most of these organisms live in the large intestine, with only about 10,000 populating the small bowel. Approximately one-third of the gut microbiome is the same across all humans, with the remaining portion being unique to each individual. (1.)


So what are these microbes for? Well, basically everything. It’s a well-known fact that our gut bacteria aid in digestion. Each time we eat, they help us extract and assimilate essential nutrients from our food, turning the remnants into waste. What many people aren’t aware of, however, is just how many other hats these microscopic beings wear when it comes to shaping our overall health. Here are several of their many functions:


Science estimates that about 70% of our immune system originates in the gut. Microbes communicate with immune cells and control how the body responds to infection. (2.)

Brain health:

Emerging research suggests the central nervous system, which is in charge of brain function, and gut microbiome are closely related. 

Blood sugar control:

A study revealed that less diverse gut microbiota are associated with type one diabetes in infants. It also discovered that certain gram-negative bacteria became more prevalent just before diagnoses. Additionally, postprandial blood sugar varies widely across the population, even when we consume the same food. And this could be due in part to differences in gut bacteria. 

Mental health:

Most of our neurotransmitters, such as serotonin and dopamine, are located in the digestive tract rather than the brain. The two organs talk to one another via the gut-brain axis, which means our mental and gastrointestinal wellbeing have a very close relationship. Not only does the food we eat have a profound effect on our mental state, but psychological stress also negatively influences digestion. 

Cardiovascular health:

The gut microbiome plays an integral role in promoting optimal levels of HDL cholesterol and triglycerides. Certain strains of bacteria convert nutrients found in red meat to TMAO, a chemical that contributes to blocked arteries, which can lead to myocardial infarction or stroke. Conversely, other species such as Lactobacilli may lower LDL cholesterol when taken in probiotic form. 

Weight control:

Many studies have shown an association between gut dysbiosis, or an unfavorable balance of good and bad microbes, and obesity. In rodent experiments, those implanted with an obesogenic microbiome gained more weight than those receiving bacteria from a lean person. This was true even when they ate the same diet. 

This by no means an exhaustive list. Hopefully, it illustrates just how important the gut microbiome is for all facets of health. Now that we’ve established that let’s move on to some of the worst things a person can do for their gut health. 


Eat a diet low in diversity.

A diverse microbiome is healthier than one with fewer strains of bacteria because different microbes have their unique defense mechanisms against harmful influences such as antibiotics.

Drink alcohol excessively.

Chronic overconsumption of alcohol is associated with gut dysbiosis. Beverages such as gin decrease the number of beneficial bacteria. However, moderate red wine consumption improves overall digestive health; this is likely due to the polyphenols present. 

Take antibiotics.

While antibiotics are crucial for such illnesses as strep throat and urinary tract infections, they can have long-lasting repercussions in the body. These powerful drugs eradicate both good and bad microbes. But levels of beneficial bacteria can also remain suppressed for years. Besides, antibiotic use can temporarily increase the population of harmful bacteria such as Clostridium. (3.)

Lead a sedentary lifestyle.

Regular physical activity has many health benefits, one being a definite alteration of the gut microbiome. Athletes’ microbiomes contain more organisms that produce butyrate, a short-chain fatty acid essential for overall health. Active people also have higher levels of Akkermansia, a microbe that plays a crucial role in metabolism and obesity prevention. 

Get inadequate sleep.

Much like the rest of our body, the gut also follows a circadian rhythm. Altering that biological clock via sleep deprivation can increase numbers of bacteria associated with weight gain, type 2 diabetes, and fat metabolism. 

Stress excessively.

Stress is unavoidable in our fast-paced society, but finding ways to mitigate its effects is crucial for maintaining a healthy gut. In mice, high stress levels increase gram-negative bacteria while decreasing beneficial populations. 

Clearly, the choices we make day-in and day-out have an overarching potential to influence our gut microbiome in either a positive or negative fashion. What we put on our plate is one of the most frequent decisions we face, so it’s time to zero in on the best foods for gut health. 



A prebiotic is a type of fiber that passes through the gut undigested. While it doesn’t provide any nutritional benefit to the host, our gut bugs love it! Microbes feed on this substance, and consuming it regularly promotes their growth and diversity. Prebiotics are naturally occurring in many foods, including legumes, oats, bananas, Jerusalem artichokes, asparagus, garlic, leeks, onions, and nuts. 


While prebiotic fiber feeds our preexisting microbiome, yogurt actually contains the bacteria that comprise it. Full-fat Greek yogurt with no added sugar is the best option because it requires the least amount of processing. (4.)


Another source of probiotics, this German delicacy is shredded cabbage that has been fermented. Make sure the kind you select hasn’t been pickled in vinegar, as it doesn’t have the same benefits. Try it on salads, sandwiches, hot dogs, or simply by the forkful!


This Korean dish is another form of fermented cabbage, except with a spicy kick to it. It has the same beneficial properties as sauerkraut and is most commonly enjoyed with meat and eggs.


Gluten receives a considerable amount of flack in the wellness world, but that is because modern-day wheat and ancient grains are two entirely different crops. The wheat cultivated today is much more concentrated than ever before, which might explain the explosion of autoimmune disease in recent years. Traditional sourdough bread, however, is much easier to digest because of the fermentation process. It also releases slowly into the body, so no need to be concerned about blood sugar spikes!


Essentially a drinkable yogurt, kefir is a probiotic drink made by the fermentation of milk. It is chock-full of good bacteria and makes a wonderful on-the-go breakfast or snack. As with yogurt, look for the simplest, most natural version possible. 


Fresh ginger has been used all over the world for centuries because of its soothing properties. Not only does it aid in the production of stomach acid which helps break down food, but it also stimulates peristalsis: the movement of contents through the digestive system. Add it to soups, smoothies, and Asian dishes, or brew a cup of homemade tea by pouring boiling water on top. 


While this breath bomb may not ward off vampires, it does keep bad gut bacteria at bay and balances yeast. It adds flavor to nearly every dish, so don’t be afraid to go crazy!

Brussels sprouts

Love or hate them, these smelly veggies are extremely beneficial to the gut. They contain sulfur compounds that help combat pathogenic bacteria such as H-pylori, which can result in peptic ulcers if left untreated.


This fermented tea beverage originated in Manchuria, and it’s full of beneficial bacteria. It’s almost like a healthier soft drink, with sweetness and carbonation making every sip more delicious than the last. 

Roquefort cheese

Hailing from France, this soft cheese contains high amounts of probiotics to replenish your gut. It pairs perfectly with crackers, fruit, or even a slice of sourdough. 

Olive oil

A staple in the anti-inflammatory Mediterranean diet, olive oil is a powerhouse of essential fatty acids and polyphenols – both of which our gut bacteria thrive on. Studies have proven it to aid in reducing intestinal inflammation, which contributes to digestive tract diseases such as Crohn’s and Ulcerative Colitis. 


An overall high intake of vegetables positively influences the gut microbiome, but even more so when it contains an equal distribution of soluble and insoluble fiber. Balancing the two is crucial for maintaining intestinal homeostasis, and peas harbor similar amounts of both. 



The trillions of bacteria residing in our guts have a profound impact that extends far beyond the confines of the digestive system. While many factors influence the balance of pathogenic and beneficial microbes within our intestines, diet is a crucial aspect – and one we have control over multiple times per day. 

Overall, a diet high in fruits, vegetables, and essential fatty acids create the most favorable environment for a healthy microbiome. Foods such as yogurt, sauerkraut, olive oil, Brussels sprouts, and traditional sourdough bread provide the prebiotics, probiotics, and polyphenols that allow beneficial gut bacteria to flourish and inhibit the growth of gram-negative microbes.