University of California at Berkeley researchers investigating the cancer-fighting effects of chemicals in cruciferous vegetables have found that a chemical known as 3,3'-diindolylmethane (DIM) appears to prevent the growth of breast cancer cells.

In addition, prostate cancer cells treated with DIM grew 70 per cent slower than untreated cells. The chemical appears to prevent cancer cells from receiving signals from the hormone testosterone. That, in turn, prevents the cells from growing.

The crucifer family includes brassicas, mustard and cress.