Low-Fat Diet Lowers Breast Cancer Recurrence Up to 42%

By reducing the amount of fat in their diet, postmenopausal women who've been treated for early stage breast cancer may lower their risk for cancer recurrence. The study of more than 2,400 women, ages 18 to 79, found that the rate of cancer recurrence after five years was 9.8% among women who ate a low-fat diet (about 33 grams of fat per day) and 12.4% among those who ate a standard diet (about 52 grams of fat per day).

That means that, compared with those on the standard diet, the women on the low-fat diet had a 24% reduction in the relative risk of breast cancer recurrence, the study said.

The most significant risk reduction-42% was noted in women on the low-fat diet whose tumors did not respond to the presence of the hormone estrogen. In women whose tumors did respond to estrogen, the risk reduction was 15%.

Breast cancer that doesn't respond to estrogen is called estrogen receptor negative (ERnegative), and women with this form of cancer usually have poorer outcomes than women with ER-positive disease.

"Reductions were predicted in women with ER-positive disease because of the association between fat intake and estrogen levels, but the effect on ER-negative disease is, if verified, a surprising and potentially important observation regarding breast cancer and signals a possible new avenue of research." said John Milner, chief of the Nutritional Science Research Group at the National Cancer Institute.