Soy Consumption May be Beneficial in Men at High Risk for Developing Advanced Prostate Cancer "Soy protein isolate increases urinary estrogens and the ratio of 2:16alpha-hydroxyestrone in men at high risk of prostate cancer," Hamilton-Reeves JM, Kurzer MS, et al, (Address: Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN 55108, USA. E-mail: mkurzer@umn.edu ). Summary: In a randomized, controlled study involving 58 men at high risk for developing advanced prostate cancer, results indicate that soy protein isolate consumption may be beneficial. The participants were randomized to 1 of 3 groups for a period of 6 months - 1) the SPI+ group: supplemented habitual diet with isoflavone-rich soy protein isolate (107 mg isoflavones/day); 2) the SPI- group: supplemented habitual diet with alcohol-washed soy protein isolate (less than 6 mg isoflavones/day); 3) the MPI group: supplemented habitual diet with milk protein isolate. Urinary estrogen metabolic profile was measured at baseline, and at 3 and 6 month end. The SPI+ and SPI- groups had significantly higher urinary estradiol (E2) excretion than the MPI group at 3 and 6 month end. Additionally, at intervention end, the SPI+ group had a significantly higher ratio of urinary 2-hydroxy estrogens to 16alpha-hydroxyestrone (2:16 OH-E1) than the MPI group. Thus, the authors of this study conclude, "Increased urinary E2 excretion and 2:16 OH-E1 ratio in men consuming soy protein isolate are consistent with studies in postmenopausal women and suggest that soy consumption may be beneficial in men at high risk of progressing to advanced prostate cancer as a result of effects on endogenous estrogen metabolism." J Nutr, 2007; 137(10): 2258-63. Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.