Eating is one of the most fundamental experiences we share, but it’s not without risk. Every time we eat we put several foreign substances into our body that may or may not hurt us, including bacteria and substances that may cause an allergic reaction. The stomach kills harmful bacteria – one of the reasons it produces acid that could scald our skin if applied – relaxes after we eat so we feel pleasantly full and stop eating, and moves the food into the upper intestine without us having to think about it at all.
The gastrointestinal nerves and muscles are silently controlled by a very complex system located in the wall of the stomach and bowel. Sometimes called the “second brain”, it connects to the big brain in the head via large nerve fibres.
We don’t usually feel the movement of food through our intestine, although sometimes we do hear noises or pass gas. Nor is digestion typically felt or sensed; often the only clue our system is working normally is that we feel comfortable but then gradually start to look forward to our next meal.
Enzymes and bacteria quietly break down the food, and we absorb the nutrients and vitamins until just the waste products remain. These move through the bowel and are expelled.
From time to time, however, this system becomes dysfunctional. For some people, eating turns from a pleasure into a pain – or worse....
