Lignans May Lower Breast Cancer Risk

NEUHERBERG, GermanyHigh exposure to lignans, a phytoestrogen found in flax and sesame seeds, may be associated with a reduced breast cancer risk in postmenopausal women but additional work is warranted to clarify the association between the two, according to a study published in the American Journal for Clinical Nutrition (May 12, 2010). A systematic MEDLINE search to identify epidemiologic studies published between 1997 and August 2009.Pooled risk estimates (REs) for total lignan exposure, dietary lignan intake, enterolignan exposure, and blood or urine concentrations of enterolactone were calculated, and according to menopausal and estrogen receptor (ER) status of tumors.

A total of 21 studies (11 prospective cohort studies and 10 case-control studies) were included in the meta-analyses. Lignan exposure was not associated with an overall breast cancer risk; however, in postmenopausal women, high-lignan intake was associated with a significant reduced risk of breast cancer. Breast cancer risk was also inversely associated with enterolignan exposure, but not with blood or urine enterolactone concentrations. The associations were not significantly different between ER-status subgroups.