Soy and cruciferous vegetables reduce cancer risk by enhancing DNA repair

Nutrients found in soy and cruciferous vegetables have recently been shown to have anti-cancer activity for hormone-responsive tumors (i.e. breast and prostate cancers). The February 13, 2006 issue of the British Journal of Cancer reported that genistein (a soy isoflavone) and indole-3-carbinol (I3C) found in vegetables such as broccoli, enhance DNA repair.

After adding increasing doses of I3C and genistein to two prostate cancer and two breast cancer cell lines, the scientists found a rise in levels of certain proteins which repair damaged DNA. Additionally, when researchers added I3C and genistein together in low doses to the cell lines, the results were synergistic, providing greater benefit than that obtained by either compound alone.

The finding could explain, in part, the protective effect these compounds have shown against some cancers. The study is also among the first to discover a cellular explanation behind the ability of increased vegetable intake to reduce the risk of cancer.

British Journal of Cancer (2006) 94,407-426.