I don't believe this is a question with a yes or no answer, as it involves things personal that go to the likes of what to eat or not eat. I've known and seen more very sincere Christians smoking, usually younger ones. I smoked when younger, hooked as a teen, yet while quite Christian, never once had thoughts of sinning against God or anybody. On the other hand, I had a consciousness of the stupidity and dirtiness of the habit, as public awareness was growing more and more, and, I suppose to some extent, sin, in that it was something of the flesh we weren't created to need, like food, water, or air which I didn't have dominion over. I also believe the Lord broke me of smoking. But to call it out as sin to others, when there are a zillion other things of the world drawing us from the mind of Christ or, such as diet, bad for health most all Christians allow, if anything, such issues should point out to all of us that there are none qualified to cast stones at somebody for smoking.
Remember, the woman caught in adultery even involved real, explicit, codified sin,
John 8:7 So when they continued asking him, he lifted up himself, and said unto them, He that is without sin among you, let him first cast a stone at her.
Romans 14:22-23 Hast thou faith? have it to thyself before God. Happy is he that condemneth not himself in that thing which he alloweth. And he that doubteth is damned if he eat, because he eateth not of faith: for whatsoever is not of faith is sin.