Cancer preventive properties of varieties of Brassica oleracea: a review.

Cabbage, broccoli, Brussels sprouts, and other members of the genus Brassica have been widely regarded as potentially cancer preventative. This view is often based on both experimental testing of crude extracts and epidemiological data. The experimental evidence that provides support for this possibility is reviewed for the commonly consumed varieties of Brassica oleracea. In a majority of cases the biological activities seen in testing crude extracts may be directly related to specific chemicals that have been reported to be isolated from one of these closely related species, thus the chemical evidence further supports the data from testing extracts and epidemiology.