Our bodies contain more microbes than human cells. Without these trillions of bacteria we wouldn’t be alive. This ‘invisible organ’ supports immune function, digestion, and even influences our behavior. More than half of the bacteria in our intestines are Firmicutes that play a key role in immune regulation and intestinal health.
Our bodies contain more microbes than human cells. Without these trillions of bacteria we wouldn’t be alive. This ‘invisible organ’ supports immune function, digestion, and even influences our behavior. More than half of the bacteria in our intestines are Firmicutes that play a key role in immune regulation and intestinal health.
More than 50%
Every person has a unique gut microbiota that consists of more than 1000 different species of bacteria. Roughly 75-90% of these species belong to the phyla Firmicutes, Bacteroidetes, and Actinobacteria. Firmicutes alone account for more than 50%. Included in this group are the genera Staphylococcus, Enterococcus, Clostridium, Faecalibacterium and the well-known probiotic Lactobacillus species. The species Faecalibacterium prausnitzii is probably the most abundant species in the human body, making up around 5% of our total gut microbiota.
Ratios determine function
The most important requirement for a healthy gut microbiota is that it is functionally diverse. One of the more well-researched functions of firmicutes is the production of butyrate. Butyrate is a fatty acid that supports both immune regulation as well as proper functioning of our intestinal lining. Given that different species of bacteria can perform comparable functions, there is not one specific combination of species which guarantees good health. The most important aspect is the proportion of the different phyla to one another. People suffering from obesity often show increased presence of Firmicutes relative to Bacteroidetes. A possible explanation for this is that over-production of butryrate by firmicutes leads to increased caloric intake. On the other hand, there is also a relationship between a decreased presence of butyrate-producing bacteria and the development of colon cancer. Some people have a genetic predisposition to these gut microbiota imbalances, but more frequently the cause lies in choices we make, and more specifically our eating habits.