Milk products and intestinal health

Milk products may improve intestinal health by means of the cytoprotective effects of their high calcium phosphate (CaPi) content. We hypothesized that this cytoprotection may increase host defenses against bacterial infections as well as decrease colon cancer risk. This paper summarizes our studies of these proposed protective effects. In rats, lactic acid in yoghurt and CaPi in milk products inhibited the gastrointestinal survival and colonisation of salmonellae. CaPi also inhibited translocation of salmonellae to extraintestinal organs, probably because it stimulates protective bacteria, like lactobacilli, and strengthens the mucosal barrier in the small intestine. In the large intestine, cytotoxic surfactants, like secondary bile acids and fatty acids can damage colonic epithelial cells and thus induce a compensatory hyperproliferation of crypt cells, which increases colon cancer risk. In rats this carcinogenic sequence is inhibited by milk CaPi. Also in humans, milk CaPi precipitates colonic cytotoxic surfactants and thus inhibits colonic cytotoxicity. These results suggest that milk products may decrease colon cancer risk. (C) 1998 Elsevier Science Ltd. All rights reserved.