No milk today

摘要

Although I am not a gastroenterologist , I feel that I am well qualified to write on this topic. My "gut rot" really started around seven years ago, in my mid-30s. I had been diagnosed as having irritable bowel syndrome as a student, but this was something more. The symptoms became quite distressing and, after a negative colonoscopy, a simple test revealed that I was lactose intolerant. The milk sugar lactose is a disaccharide found naturally only in milk products. In non-sufferers it is split in the small intestine by lactase into glucose and galactose, which are readily absorbed. In the absence of endogenous lactase enzyme, the sugar passes into the large bowel, where it is broken down by lactobacilli, part of the normal flora. The products of this digestion include hydrogen, some of which is absorbed and excreted via the lungs, the remainder leaving by an alternative route. The raised level of hydrogen in exhaled breath forms the basis of the lactose tolerance test. In addition, unabsorbed lactose has an osmotic effect not unlike that of lactulose, a synthetic laxative, increasing the amount of fluid retained in the bowel. It does not take too much imagination to see the effect that this fluid and gas might have on the colon, with the diarrhoea, colic, and flatulence being similar to the symptoms of irritable bowel.