IBD Is More Common in Canada – Why?

IBD stands for inflammatory bowel disease, and comprises ulcerative colitis and Crohn’s disease. (It’s not to be confused with IBS, or irritable bowel syndrome.) IBD, in general, is more common, in northern countries, but it’s especially common in Canada . About 0.5% of Canadians, or one in 350 persons, have it. A survey published in the American Journal of Gastroenterology reports that the frequency is the highest reported for any country; 194 cases of ulcerative colitis and 234 cases of Crohn’s disease for every 100,000 Canadians.

The obvious question is “why?” The hygiene hypothesis supplies an answer. Living in an environment that’s very clean or sterile as a child means the intestines are not exposed to the same numbers or types of bacteria that one would be exposed to in a tropical country. (This is obviously the case for Canada .) Lack of exposure to bacteria means the intestines cannot tolerate bacteria as one gets older, and, in the words of the investigators, “they start to destroy themselves”.

What’s the answer? Well, if you’re born elsewhere, you may have natural protection; Asian immigrants have less IBD than Caucasians. Maybe one could “buy” some protection by eating more yogurt? That remains to be researched. But yogurt today tastes so good that it’s worth trying.