Origin
Our body is the habitat of trillions of bacteria. This population of bacteria is called the microbiome. Each part of the body possesses a specific microbiota. Bacteria colonizes the whole body. The composition of the gut microbiota varies by dietary and lifestyle habits, among other factors, and therefore differs between individuals
The gut microbiota not only live in the human gut, but also play large roles in maintaining human health. One of the most fundamental roles of the gut microbiota is in digestion; the gut microbiota strongly influence how ingested food or medicine is digested, absorbed and stimulates gastrointestinal cells.
On the other hand, the substances produced by digestion, known as metabolites, also affect the composition and functions of the microbiota. Therefore, to evaluate the intestinal environment, it is important to understand both the composition of the gut microbiota and the availability of metabolites.