In regards to scientific research on herbs, please do NOT use Wikipedia or Snopes. Search the National Library of Medicine's PubMed research database. It covers pretty much all scientific journals and if the research was done using government funds usually the full paper is available to download. If not, at least the abstract is posted.

Here's a good example: Capsaicin Supplementation Reduces Physical fatigue and Improves Performance in Mice

-Blast