I grew up with the notion and still maintain the notion that illegal drugs are not good for you.
Being "good for you" is relative. I doubt there is a "legal" pharmaceutical that is 100% "good for you". All have side-effects, some of which can be extremely harmful. But they are utilised simply because their absence would cause greater harm. Thalidomide was legal . . . and touted as good for you. Wonderful cure for morning sickness . . . shame about the side-effects. I've been legally prescribed drugs that have almost killed me.
Legality is a poor way of establishing what is harmful and what is not . . . it may be time to drop the notion.
MJ is illegal in NZ . . . no medical concessions. I won't bore you with my state of health . . . but I grow my own and use it on a regular basis . . . as do my wife and 2 of my 3 grown children (the other doesn't like the effect). The medical benefits are manifest, and I also enjoy the narcotic effect . . . without feeling guilty about it.
I don't drive while heavily influenced and don't drink alcohol. All my family are responsible users. If people wan't to be dangerous and irresponsible . . . it doesn't matter how they gas their tank.
I would say that the pharmaceutical companies have a large stake in this . . . it's too easy to supply yourself, and is too good as a medicine.
Trust Uncle Carl . . . not the Govt.