Soy study suggests reduced prostate cancer risk
October 04, 2007
by Eric Schroeder
ST. PAUL, MINN. — A new study appearing in the Oct. 1 issue of The Journal of Nutrition suggests consumption of soy protein may play a key role in reducing the risk of prostate cancer in men. As part of the study, 58 men supplemented their diets with 1 of 3 protein isolates — isoflavone-rich soy protein isolate (SPI+), alcohol-washed soy protein isolate (SPI-), or milk protein isolate (MPI) — each with 40 grams of protein per day. Both soy groups had higher urinary estradiol excretion than the MPI group at three and six months. "After taking biopsies of prostate tissue, androgen receptors were reduced in the prostate, which is consistent with a reduced risk of prostate cancer," said Dr. Mindy Kurzer, lead author of the study and a professor in the Department of Food Science and Nutrition at the University of Minnesota. "In addition, significantly fewer of the men who consumed soy protein progressed to cancer by the end of the six-month study. We are encouraged by the results, but more studies must be performed."