Addiction is nothing more than a person's physical and psychological reliance on a substance. And this nicotine reliance is referred to as a smoking addiction. Nicotine is a substance found in cigarettes that makes quitting difficult. Nicotine causes a fleetingly pleasurable impact on the brain, and this effect encourages smoking another cigarette and developing an addiction. Use of tobacco damages all of your body's organs. In addition to nicotine, smoking tobacco exposes your lungs, blood, and organs to more than 5,000 toxins, many of which are carcinogens (chemicals that cause cancer). Smoking-related harm can dramatically reduce your longevity. Risk factor of smoking includes: