Did you know that your body is a host to bacteria? The human microbiome consists of trillions of bacteria who call your body home. The majority of these are located in your gut (gastrointestinal tract). It’s a mutually beneficial relationship: the bacteria rely on us and we rely on them. In fact, the role gut bacteria play in health is something we are constantly learning about and is the subject of much of the current research.

The levels of good and bad bacteria in the gut are constantly in flux due to changes in our diet and lifestyle, which start at a young age. Babies are born with a sterile gut, which becomes inhabited on different types of bacteria based on what they consume. The effect of diet on bacteria continues into adulthood.

Bacteria in the gut have a number of beneficial functions. By sticking to our gut cells, good bacteria physically prevent pathogenic bacteria (disease-causing) from colonizing by secreting proteins. Gut bacteria also produce nutrients such as vitamin K, biotin, and vitamin B12, which all play a role in the maintenance of good health.

Given the beneficial effects of gut bacteria, it makes sense to try to support them. One of the easiest ways to support your gut bacteria is to eat prebiotics. Prebiotics are fiber and fiber is found in ALL whole food sources of plants.  Resistant starches are another prebiotic which are also found in plant and have a similar effect. They can be found in unripe bananas, pulses,  potatoes, and potato products.

Prebiotics pass through the gastrointestinal tract undigested until they reach the colon. Here, they act as food for our gut bacteria. The bacteria in the gut ferment these fibers and produce short-chain fatty acids, which in turn provide energy to the cells lining the gut. These fatty acids help us too, as they create an environment that is unsuitable for pathogenic bacteria.

Another way to help your body is to actually eat healthy bacteria or probiotics. These are found in fermented foods such as sauerkraut, kimchi, and kombucha, along with commercially prepared probiotic supplements. Check out this article for food sources of probiotics, and this menu for ways to use them. If you wish to take a probiotic supplement, ask your registered dietitian for advice as many probiotics are not scientifically proven to have any effect.