The role of dietary phytosterols in colon carcinogenesis

Epidemiological and experimental studies have shown that increased intake of plant foods and decreased meat consumption are correlated with a decreased risk for colon cancer. Many components of plant foods are suggested to mitigate colon carcinogenesis, including vitamins, minerals, and dietary fiber. Phytosterols are a common component of plant foods consumed in relatively large quantities by vegetarians, who are at lower risk for colon cancer development than individuals on a Western diet low in phytosterols. In addition, phytosterols have been shown experimentally to inhibit colon cancer development. Dietary cholesterol, although structurally similar to the phytosterols, is correlated etiologically to the incidence of colon cancer, with changes in serum cholesterol levels and fecal bile acid profiles suggested to increase susceptibility to colon tumorigenesis. The objective of this paper is to discuss the effect of dietary phytosterols on cholesterol and bile acid metabolism and how these effects may lead to a decreased risk for colon cancer development.