It was lifted by the IFpa/Oco allowing it to be used for their competetions. The best research that has been done on it is from Henry Lardy and his collaborators at the University of Wisconsin.
if your interested in it read~ and most important look at the Facts~after the claims made for and against.
also these can have interactions with -dhea
Substances metabolized by the CYP3A4 enzyme
Summing this all up a month supply at 300-1400 mgs is just as safe as the food we eat.