Beta sitosterol is a plant sterol often found in fruits, vegetables, nuts, and seeds, and is abundantly in saw palmetto, pumpkin seeds, and pygeum africanum.
Over the past few years, concentrated extracts of this particular phytosterol have been tested for supporting normal cholesterol levels and promoting prostate comfort and health. Roger Mason's book on prostate health is considered by many to be essential reading when it comes to a healthy, alternative approach to prostate health. The most positive reviews seem to come from men who have tried Mason's advice on diet and supplements (including beta sitosterol).
It may have additive effects with herbs and supplements possessing similar properties like chromium picolinate, flaxseed, garlic, gaur gum, niacin, oat bran, and psyllium!