Saw Palmetto is a 5 alpha reductase, which means it inhibits the production of DHT. In other words, it's an anti androgen.
Since DHT is necessary for muscle "hardness" and libido, I do not recommend Saw Palmetto.
DHT also acts as an anti estrogen. Using Saw Palmetto increases the sensitivity toward gyno.
Other than that, I never believed DHT was the major culprit in prostate problems. New studies confirm this. It's excess estrogen that is a bigger factor.