The connection between tar and nicotine is, put simply, smoking. Tar accumulates in a smoker's body, and this accumulation is thought to contribute to a wide range of negative effects, including emphysema and cancer. A connection between tar and nicotine has long been a component of tobacco marketing, because the amounts of both substances generally are required to be disclosed when a cigarette enters the market. Tar and nicotine are lumped together in various written and oral communications about the dangers of smoking, because each substance can be linked to an unhealthy result, but tar and nicotine actually act on separate mechanisms within the body.
"Tar" is the term given to a range of compounds that are produced when tobacco undergoes partial combustion during smoking. Tar is so named because it physically resembles road tar, although it is chemically different. Tar and nicotine are found alongside one another in commercial tobacco products such as cigarettes, but nicotine inhalers, nicotine gum and nicotine lozenges are all sources of nicotine that do not include tar.
Nicotine is a stimulant in low doses and is recognized as the key addictive component in cigarettes. Nicotine and cancer might not have a strong correlation, but because nicotine is an addictive substance, there are a host of other health problems that can result from its use. Once an individual is addicted, it can be extremely difficult for him or her to break free of the addiction, and because of the way that nicotine affects the metabolism, withdrawal symptoms can be quite unpleasant.
The brain's reward system is modified through addiction to nicotine, and depression can result from its unexpected absence. It is difficult to alter the smoking behavior if an individual is experiencing emotionally painful withdrawal symptoms. Therefore, nicotine replacement, which omits tar, is considered a stepping stone on the path away from actual tobacco smoking.
Chemical dependency is never ideal, so the use of nicotine lozenges or other replacements should be a temporary measure. Doctors, however, recognize that eliminating tar from the smoker's system significantly reduces the risk of irreversible damage, so nicotine replacement is often prescribed as an initial measure for individuals who hope to quit smoking. In the absence of tar produced by smoking, the body is able to heal itself, and lung function makes progress back toward optimal levels. This can be an encouraging feeling for the individual who is quitting, and he or she must then attempt to break free of nicotine as a separate measure, which is easier for some than quitting tar and nicotine together.