One of the most powerful ways to reduce your risk of breast cancer is to eat freshly ground flaxseeds regularly.  Flaxseeds are the richest source of a type of phyto-estrogen called lignans.  More specifically flaxseeds contain lignan precursors.  When flaxseeds are eaten, bacteria in the digestive tract convert lignan precursors into two main lignans called enterodiol and enterolactone.  This conversion is dependent on sufficient quantities of good bacteria being present in the digestive tract.

Lignans have the ability to bind to estrogen receptors in breasts and exert an anti-estrogenic effect there. Experiments done on mice with estrogen receptor positive breast cancer, and experiments performed on isolated cells in test tubes (in vitro studies) have confirmed the ability of flaxseeds to block the action of estrogen induced tumor growth and even reduce tumor size.  Flaxseeds were also able to block the growth of new blood vessels in solid tumors (called angiogenesis), thereby reducing the ability of tumors to spread.  Flaxseeds increased cell apoptosis (cell death) in tumors. When flaxseeds are eaten at the same time as taking the drug tamoxifen, they improve the cancer fighting effects of tamoxifen.

Flaxseeds are delicious when freshly ground. You can add them to smoothies, stir them into yogurt or sprinkle the ground seeds onto fruit. For more information on reducing the risk of breast cancer, or cancer recurrence, see my book The Breast Cancer Prevention Plan.


Bergman Jungestrom M, et al. Flaxseed and its lignans inhibit estradiol-induced growth, angiogenesis and secretion of vascular endothelial growth factor in human breast cancer xenografts in vivo.  Clin Cancer Res 2007;13(3):1061-7
Chen J, et al. Flaxseed alone or in combination with tamoxifen inhibits MCF-7 breast tumor growth in ovariectomized athymic mice with high circulating levels of estrogen.  Exp Biol Med (Maywood) 2007;232(8):1071-80