Not that I'm putting a stake into either side of this debate, but workaholism is clearly also extremely detrimental to your health; there are ways to abuse drugs while being careful about your health just like there are ways to work 70 hours a week and still take care of yourself --- it's just that in both cases people rarely pull it off.

Heroin is actually not that bad for your health per se -- it's the stretching agents that'll get you.