These exposures probably account for the fact that oral and esophageal cancer risks are similar among cigar smokers and cigarette smokers. Cancer of the larynx occurs at lower rates among cigar smokers who do not inhale than among cigarette smokers. Lung cancer risk among daily cigar smokers who do not inhale is double that of nonsmokers, but significantly less than the risk for cigarette smokers. However, the lung cancer risk from moderately inhaling smoke from five cigars a day is comparable to the risk from smoking up to one pack of cigarettes a day. There are, however, some differences between cigar and cigarette smoke due to the different ways cigars and cigarettes are made.
Cigars go through a long aging and fermentation process.
During the fermentation process, high concentrations of carcinogenic compounds are produced. These compounds are released when a cigar is smoked. Also, cigar wrappers are less porous than cigarette wrappers. The nonporous cigar wrapper makes the burning of cigar tobacco less complete than cigarette tobacco. As a result, compared with cigarette smoke, the concentrations of toxins and irritants are higher in cigar smoke.