The digestive system is a highly complex series of mechanisms, both for getting things into the body, and for keeping them out.  Through a series of connected mechanical and chemical processes, starting even before we get our teeth into something, it breaks down food so that it can be absorbed into and used by the body.  At the same time, barriers such as the hydrochloric acid in the stomach kill most micro-organisms, and prevent them from infecting us by that route.  Being so complex, and in the first line of battle, it should be no surprise that things often go wrong with the digestive system.   Such a “digestive failure” can affect our whole bodies - and minds.

The first step in the process of digestion occurs in the brain, when we either see or think about or smell food.  This stimulates the production of saliva and gastric juices, in readiness for eating.  State of mind is therefore able to make a large difference to digestion.  Depression reduces our output of hydrochloric acid; anger increases it.

When we put food into our mouths, we chew it in order to break it down into small particles, and increase the surface area on which first the saliva and then the other digestive juices can work.  Grandmothers’ instructions to “chew every mouthful 32 times” may have some basis.  There is even a case on record of a man who suffered from Urticaria when he failed to chew his food, but had no problems when he chewed it thoroughly.