What if you were to look at it from a strictly medical viewpoint, does it do anything other than injurious things? I suppose you could argue that it relieves stress which may prolongue life in one sense/prevent suicide perhaps? But what about the number of deaths caused by smoking? Preventable in terms of cause by not smoking, maybe islam would prevent those particular deaths. But again its, would I rather smoke, die younger, and have fun than live a boring life worshiping something never proven, I think I would