Primary adult lactose intolerance protects against development of inflammatory bowel disease

The have compared the incidence of inflammatory bowel disease (IBD) to the prevalence of lactose malabsorption (LM) in several countries. Our observations indicate that IBD is rare where LM is highly prevalent. The correlation between incidence of Crohn's disease and LM is -0.93, p < 0.01, the correlation between incidence of ulcerative colities and LM is -0.89, p < 0.01. We, therefore, propose that LM results in the formation of volatile fatty acids which may inhibit multiplication of potentially pathogenic organisms.