In our intestines we have about 500 different species of micro-organisms, mostly bacteria. Usually bacteria are thought to be the bad guys which make us ill, but in fact we need these tiny tenants to keep food bugs and upset stomachs at bay and to produce a number of useful substances for our health. These good guys are called “the intestinal flora”. There are also fungi among them. These can be yeasts, similar to the ones we know for baking bread or making wine or moulds similar to the tasty ones, which make cheeses. Or they can be the black stuff which causes food to ferment and decay. Usually their numbers are small.

Candida is a kind of yeast, a tiny single celled organism, which in normal circumstances is a harmless part of our intestinal flora. However, sometimes when we are not so fit these Candida yeasts can develop the ability to get nasty, grow into large numbers and cause symptoms.