Throughout history, what we eat has varied widely depending on what was available, but it has always been crucial to our overall health. Our brains and digestive systems have evolved and must stay in close contact to ensure we get the necessary nutrients. We also require a sound alarm system to prevent us from eating the wrong thing or slowing down digestion when necessary.

The relationship between the gut and the brain is complex and two-way. Signals are transmitted in both directions between the digestive and central nervous systems; any health or disease in either system can affect the other. The enteric nervous system, the vagus nerve, and the gut microbiome are all important components in this connection.