Why? Because of the more than 4,000 chemicals in tobacco smoke, nicotine is the primary one that acts on the brain, altering people's moods, appetites, and alertness in ways they find pleasant and ...

Why? Because of the more than 4,000 chemicals in tobacco smoke, nicotine is the primary one that acts on the brain, altering people's moods, appetites, and alertness in ways they find pleasant and ...