The gastrointestinal (GI) tract of a healthy mammal is home to a complex community of bacteria. This microbial community is often called “microbiota,” “gut flora,” or “beneficial bacteria.” These microbes have evolved with us to coexist in a mutually beneficial relationship.
An Introduction to Gut Microbes
We need beneficial gut microbes for proper B vitamin production, digestion, and assimilation. Some bacteria also synthesize vitamin K. In fact, we need bacteria for synthesization, digestion, and assimilation of many vitamins, minerals, proteins, fats, and many other nutrients. Healthy bacteria also keep the population of other microbes (like candida) down to healthy levels. Healthy bacteria colonies form a biofilm that keeps the intestinal wall healthy and acts as a barrier against pathogens. Healthy bacteria move slowly and crowd out unwanted pathogens. A healthy gut biofilm is a home to thousands of different beneficial bacteria, the more the better. And they don’t just reside on our gut. Some of them can and do pass through the gut wall and they live all over our body. It’s often said that bacteria in our body outnumber our own cells by about ten to one. That’s incorrect, but there are more bacteria cells than human cells in the human body. The ratio is about 39 bacterial cells to every 30 human cells.
