We do. But man getting evidence in this area is hard. Human tendencies towards pleasure (from basic desire for good feelings/self-gratification to utterly destr

We do. But man getting evidence in this area is hard. Human tendencies towards pleasure (from basic desire for good feelings/self-gratification to utterly destructive addiction) and towards greed (from dealers/cartels to HMOs) are both actively confounding the discovery and codification of good data regarding drug use, benefits, and abuse.