Soy may prevent breast cancer
May 23, 2006
Women who eat lots of soy foods appear to have a lower risk of breast cancer, researchers have discovered.
Women who eat lots of soy foods appear to have a lower risk of breast cancer, researchers have discovered.
Teams at Johns Hopkins University in Baltimore and Georgetown University in Washington looked at 18 different population-based studies of soy and breast cancer. They found an overall relative reduction of 14% in breast cancer risk in Caucasian women who ate soy, they reported in the Journal of the National Cancer Institute recently.
Many of the studies involve people in Asia whose diets are naturally high in soy. In contrast, Western women often seek short cuts by taking soy supplements.
“The important aspect is eating actual soy-based foods like tofu, not highly purified isoflavone supplements. Highly-refined components of soy can have very different biological effects than eating tofu or drinking soymilk,†said Bruce Trock, an associate professor of urology, epidemiology at Johns Hopkins. Soy is high in compounds called isoflavones, which may block estrogens, promote the destruction of faulty cells, including tumour cells, and fight inflammation.
Trock said soy exposure early in life may be the most important factor in reducing cancer risk.
One of the studies showed Asian-American soy-eaters born in Asia had lower rates of breast cancer than those born in the United States, possibly reflecting soy exposure in-utero and before puberty.
Ends
Teams at Johns Hopkins University in Baltimore and Georgetown University in Washington looked at 18 different population-based studies of soy and breast cancer. They found an overall relative reduction of 14% in breast cancer risk in Caucasian women who ate soy, they reported in the Journal of the National Cancer Institute recently.
Many of the studies involve people in Asia whose diets are naturally high in soy. In contrast, Western women often seek short cuts by taking soy supplements.
“The important aspect is eating actual soy-based foods like tofu, not highly purified isoflavone supplements. Highly-refined components of soy can have very different biological effects than eating tofu or drinking soymilk,†said Bruce Trock, an associate professor of urology, epidemiology at Johns Hopkins. Soy is high in compounds called isoflavones, which may block estrogens, promote the destruction of faulty cells, including tumour cells, and fight inflammation.
Trock said soy exposure early in life may be the most important factor in reducing cancer risk.
One of the studies showed Asian-American soy-eaters born in Asia had lower rates of breast cancer than those born in the United States, possibly reflecting soy exposure in-utero and before puberty.
Ends