Research scientist James Greenblatt’s provocative idea — that numerous psychiatric woes can be solved by targeting the digestive system — is increasingly reinforced by cutting-edge science. For decades, researchers have known about the connection between the brain and the gut. Anxiety often causes nausea and diarrhea, and depression can produce changes in appetite. The connection may have historically been well established, but scientists thought communication was one way: it traveled from the brain to the gut, and not the other way around.
While mental health researchers have established a compelling link between gut bacteria and mental health, they’re still trying to figure out the extent to which the human microbiome — once it’s populated in early childhood — can be transformed. “The brain seems to be hardwired for anxiety by puberty and early adolescence,” Foster said. If the microbiome is part of that hardwiring, then it would suggest that once we pass a certain threshold, the impact of bacterial tweaks on problems like depression and anxiety might wane.”