The gut has been described as the second brain. For example, neurotransmitters are produced by microbes. cytokine release by the gut. Some microbes produce steroids which can travel and affect the brain. Other small molecules made by microbes can have an effect on the brain. On the other hand the brain can have an effect on microbial health. We know depression can have a negative effect on your gut community. Other things like stress and anxiety can also have a negative effect. These can lead to IBD and ASD. Antibiotic treatment can have help autism symptoms.
