Lots of Soy Lessens Endometrial Cancer Risk
Soy Foods May Cut Uterine Cancer Risk -- Especially for Heavy Women
May 27, 2004 -- The more soy foods a woman eats, the lower her risk of endometrial cancer.
About nine out of 10 uterine cancers arise in the lining of the uterus -- the endometrium. It's a common cancer in women. But Asian women get three to five times less endometrial cancer than Western women do. They also eat about 25 times as much soy food.
Is there a connection? Wang Hong Xu of the Shanghai Cancer Institute in China, and colleagues identified 832 Chinese women with endometrial cancer. They compared these women's soy intake with that of 846 age-matched women without cancer.
Sure enough, a woman's risk of endometrial cancer went down as the amount of soy food she ate went up.
"Regular intake of soya foods is associated with a reduced risk of endometrial cancer," Xu and colleagues conclude. Their report appears in the May 29 issue of the British Medical Journal.
The effect was stronger in women with higher body mass and with larger girth.
It's not completely clear why soy foods might fight cancer. Because fat cells produce estrogen, heavier women tend to have more estrogen than slim women do. This supports the idea that soy somehow protects against the cancer-inducing effects of estrogen. But soy seemed to protect women both before and after menopause -- and estrogen hormone therapy didn't diminish the protective effect.
Excellent sources of soy include soy milk, raw young soy beans (edamame), tofu, tempeh, and dried soy beans (soy nuts). Soy fiber products are also available.