Can you spot a smoker?
I'm friends with a doctor who says he can tell who smokes just by looking at them. He says he can judge by looks and not smell, voice, cough, etc. That smokers have a certain look... something about their complexion, lips, skin turgor, is how he can spot the smokers, even if they are only teenagers. I think he's full of crap. I can spot someone who's been smoking half their life based upon that assessment, but someone who is 19? I don't think so.