All commercial tobacco products are toxic when used as intended. So-called light cigarettes are not less toxic, and consumers are deceived to believe they are.
Nicotine alters the structure of the nervous system's receptor up-regulation.
It also alters the modulation of neurotransmitters, hormones, and brain metabolic and electrical activity. It produces physical and psychological dependence, tolerance, reinforcement, and mood altering effects. The cigarette was specifically designed by the tobacco industry to administer the correct dosage level so to maximize the achievement of these effects. Tobacco may be used for self-medication of depression, anxiety, attention deficit disorder or stress. There are individual differences to nicotine sensitivity.