Nicotine is also a known carcinogen (cancer causing chemical). All tobacco products contain many carcinogens. As an example, a burning cigarette for has around 60 cancer causing agents that the user inhales as they are smoking. Others are exposed to these carcinogens by breathing second-hand smoke. Some of the poisons inhaled are arsenic, tar, carbon monoxide, ammonia, DDT, and cyanhydric acid, as well as many others.

Dip and chewing tobacco is sometimes thought of as a safer alternative than smoking because it contains fewer carcinogens; however, it contains more nicotine per serving. As a result, addiction is imminent and the chance of cancer of the head or neck is greatly increased when compared likelihood of developing lung cancer due to smoking, even among younger users. Furthermore, the type of mouth cancer one would get from dipping and chewing is very aggressive and will likely require extensive and facial deforming surgery.

Cancer statistics provide powerful incentive to stop smoking. Lung cancer is almost never felt by the person infected, so by the time it is detected it has already reached an advanced stage or spread to other surrounding organs.