Researchers believe poor diet, lack of sunlight and low levels of vitamin D may have led to the rise.

Cases of inflammatory bowel disease, which includes Crohn's disease and ulcerative colitis, have soared.

A total of 436 under-16s were diagnosed with inflammation of the colon and small intestine between 2003 and 2008, compared with 260 between 1990 and 1995.

David Wilson, professor of paediatric gastroenterology and nutrition at the University of Edinburgh, said: "Children in Scotland are more likely to develop IBD than those in any other nation in the UK."

It was found that youngsters were being diagnosed with Crohn's disease and ulcerative colitis at an earlier age.