Lactic acid bacteria are one of the most important microorganisms for food fermentation and gut health. It is called “lactic acid” because it is not derived from milk but is produced as a result of fermentation.
These bacteria feed primarily on sugars and carbohydrates. When lactose or plant sugars are fermented, lactic acid is released, which lowers the pH and creates an environment that is inhospitable to harmful microorganisms. This is why lactic acid bacteria are so effective at preserving foods such as yogurt, kefir, sauerkraut, and sourdough.
In fermented foods such as yogurt and kefir, these bacteria cause physical and nutritional changes. occurs when milk ferments.
In the intestines, lactic acid bacteria play a supporting role rather than a dominant one. They tend to act in the upper gastrointestinal tract and early in the colon, where they help regulate acidity and prepare nutrients for other microorganisms downstream.
An important point that is often misunderstood is that lactic acid bacteria do not permanently colonize the intestines in large numbers. Their value lies in what bacteria do during transit, such as fermenting food, producing useful metabolites, and creating conditions that benefit other beneficial bacteria.
Traditional diets regularly provided these bacteria through fermented foods. This is often not the case in modern diets, which is why interest in fermentation has returned. Not as a trend, but as a rediscovery of biological processes that humans have relied on for thousands of years.
