Milk and dairy products in cancer prevention: focus on bovine lactoferrin

Milk and dairy products constitute an important part of the western style d iet. A large number of epidemiological studies have been conducted to deter mine effects of consumption on cancer development but the data are largely equivocal, presumably reflecting the different included components. It has been proposed that whereas fats in general could promote tumor development, individual milk fats like conjugated linoleic acid could exert inhibitory effects. There is also considerable evidence that calcium in milli products protects against colon cancer, while promoting in the prostate through sup pression of circulating levels of 1,25-dihydroxyvitamin D3. Whey protein ma y also be beneficial, as shown by both animal and human studies, and experi mental data have demonstrated that the major component bovine lactoferrin ( bLF), inhibits colon carcinogenesis in the post-initiation stage in male F3 44 rats treated with azoxymethane (AOM) without any overt toxicity. The inc idence of adenocarcinomas in the groups receiving 2% and 0.2% bLF were thus 15% and 25%, respectively, in contrast to the 57.5% control value (P < 0.0 1 and P < 0.05, respectively). Results in other animal models have provided further indications that bLF might find application as a natural ingredien t of milk with potential for chemoprevention of colon and other cancers. (C ) 2000 Elsevier Science B.V. All rights reserved.