It's okay to smoke tobacco. Tobacco doesn't kill you, Native Americans are culturally involved with tobacco smoking and they live longer than we ever will. There are over 400 chemicals in cigarettes, and those chemicals are what makes them dangerous aside from the nicotine. The nicotine is the addictive part that gives your body a high-feel good feeling and it takes your neurotransmitters and gives them an overdose of them, and then once you get off the high, your body doesn't have any at all really, which makes you feel like you need more nicotine because you are replacing your natural source of neurotransmitters, with a drug that hyper-creates them temporary, building a bluff to your brain. And so you'll smoke another cig to make up for the loss etc...