An interesting study showed that taking SOD — superoxide dismutase — an enzyme that clears up free radicals that can contribute to erectile dysfunction — has some benefit (at least in rats).
Read it here: LINK to article.
The good thing about SOD is that you can buy it at a health food store. The bad news is that SOD breaks down in your digestive tract; so you have to buy a version that is absorbed without being digested. They have these at health food stores. This is one of the supplements I take every night, by the way.
Here’s the experiment I would like: take all of these supplements, and try them one at a time with rats. For example, which would be better – arginine, Viagra, SOD, etc etc.