Soy protein is beneficial to approx 80% of women. Women who are considered secretors (a term that describes the way food is absorbed into the blood stream) can benefit largely from SOY...more so from whey protein, in fact. However, men should stick to whey protein, and women who work out, should still drink a whey protein shake after they work out. Soy protein feeds your muscles over a longer period of time as opposed to whey which can be utilized by the body immediately.