This supplement was effective from an anecdotal standpoint. I used this while attempting to recover my testosterone baseline level. About a week in of 2 caps a day I noticed better sleep, an increase in libido, and better recovery time between bouts of activity. In a two month period I raised my testosterone from a total of 86 to over 400 and I have no doubt this supplement helped contribute to that number. Was it absolutely necessary? Of course not, but at the price and potential benefit it is a no brainer.