Nation,
There have been too many times to count of how often people ask about supplements. There is a handy website you can go to that gives an overview as well as recommendations and links to studies describing the efficacy of all types of supplements, herbs, and other natural products:
When you first click on the link it will bring you to www.examine.com/welcome to try to sell you something. Just backspace the "welcome" part so the URL becomes just www.examine.com so you get to the main site.
Use the information for what it is worth. Also recognize that many of the studies are either incomplete or the reviewer(s) have specific biases due to external factors like influence from the AMA or pharmaceutical industry. A perfect example is Saw Palmetto. It is an extract from a berry of the dwarf palm tree native to South Florida that has been used by Native Americans for centuries and countries like France, Germany, and Canada today to treat Benign Prostate Hyperplasia (BPH) and other prostate symptoms as men age. Many studies have shown it is as effective as the drug Finasteride (Proscar and Propecia) which has serious sexual side effects. The JAMA found evidence that it is effective then 8 years later the study authors changed their view citing issues with "consistent potency of the extract and not using standardized methods to determine efficacy" which is the pharmaceutical industry's way of trying to refute studies which obviate the need for their drugs.
I have written articles/posts on supplements and we have discussed them at length on this board. Outside of creatine, whey, and other protein supplements, many others are useless especially testosterone boosters, NO boosters, and pre-workouts. This website is a good central point to do your research before you buy.
John
