Bacteroides, Bifidobacteirum, Faecalibacterium, Ruminococcus– these are the names of some of the 100 trillion bacteria who are living and working in your gut. These microscopic critters, collectively known as the microbiome, help our body to digest food, process nutrients, make vitamins B and K, and produce immune molecules that fight inflammation and heal wounds. The most impressive role of this busy workforce may be, surprisingly, in the brain.
While the digestive tract and the brain feel far apart in your body, they are actually connected via a 24/7 direct line of biochemical communication, set up by special nerve cells and immune pathways. It’s called the gut-brain axis. Down in the gut, bacteria make neuroactive compounds, including 90% of our neurotransmitter serotonin, which regulate our emotions. In turn, the brain can send signals to the gastrointestinal system, for example, to stimulate or suppress digestion.
A healthy microbiome is a diverse microbiome. A rich community of varied species protects against one dominating and causing trouble in our gut and beyond. Shifts in the composition or function of the microbiome have been implicated in inflammatory bowel disease, autism, and blood cancers. Researchers are now discovering that a disrupted microbiome, in certain contexts, may contribute to Alzheimer’s disease and related conditions that cause dementia.
