Unless we are elite athletes routinely participating in highly competitive events, most of us simply do not need dietary performance supplements. In any case, never ever take supplements without the advice and consent of your doctor or licensed dietitian. Commercial dietary supplements—even so-called “natural” ones—are usually little more than processed concoctions of mysterious chemicals and ingredients. Buyer beware.
http://breakingmuscle.com/health-medicine/shocking-things-you-need-to-know-before-taking-supplements