Cigar Smoking and Cancer

by National Cancer Institute

1. What are the health risks associated with cigar smoking?

Scientific evidence has shown that cancers of the oral cavity (lip, tongue, mouth, and throat), larynx, lung, and esophagus are associated with cigar smoking. Furthermore, evidence strongly suggests a link between cigar smoking and cancer of the pancreas. In addition, daily cigar smokers, particularly those who inhale, are at increased risk for developing heart and lung disease.

Like cigarette smoking, the risks from cigar smoking increase with increased exposure. For example, compared with someone who has never smoked, smoking only one to two cigars per day doubles the risk for oral and esophageal cancers. Smoking three to four cigars daily can increase the risk of oral cancers to more than eight times the risk for a nonsmoker, while the chance of esophageal cancer is increased to four times the risk for someone who has never smoked. Both cigar and cigarette smokers have similar levels of risk for oral, throat, and esophageal cancers.

The health risks associated with occasional cigar smoking (less than daily) are not known. About three-quarters of cigar smokers are occasional smokers.

2. What is the effect of inhalation on disease risk?

One of the major differences between cigar and cigarette smoking is the degree of inhalation. Almost all cigarette smokers report inhaling while the majority of cigar smokers do not because cigar smoke is generally more irritating. However, cigar smokers who have a history of cigarette smoking are more likely to inhale cigar smoke. Cigar smokers experience higher rates of lung cancer, coronary heart disease, and chronic obstructive lung disease than nonsmokers, but not as high as the rates for cigarette smokers. These lower rates for cigar smokers are probably related to reduced inhalation.

3. How are cigars and cigarettes different?

Cigars and cigarettes differ in both size and the type of tobacco used. Cigarettes are generally more uniform in size and contain less than 1 gram of tobacco each. Cigars, on the other hand, can vary in size and shape and can measure more than 7 inches in length. Large cigars typically contain between 5 and 17 grams of tobacco. It is not unusual for some premium cigars to contain the tobacco equivalent of an entire pack of cigarettes. U.S. cigarettes are made from different blends of tobaccos, whereas most cigars are composed primarily of a single type of tobacco (air-cured or dried burley tobacco). Large cigars can take between 1 and 2 hours to smoke, whereas most cigarettes on the U.S. market take less than 10 minutes to smoke.

4. How are the health risks associated with cigar smoking different from those associated with smoking cigarettes?

Health risks associated with both cigars and cigarettes are strongly linked to the degree of smoke exposure. Since smoke from cigars and cigarettes are composed of many of the same toxic and carcinogenic (cancer causing) compounds, the differences in health risks appear to be related to differences in daily use and level of inhalation.

Most cigarette smokers smoke every day and inhale. In contrast, as many as three-quarters of cigar smokers smoke only occasionally, and the majority do not inhale.

All cigar and cigarette smokers, whether or not they inhale, directly expose the lips, mouth, tongue, throat, and larynx to smoke and its carcinogens. Holding an unlit cigar between the lips also exposes these areas to carcinogens. In addition, when saliva containing smoke constituents is swallowed, the esophagus is exposed to carcinogens. 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.

5. What are the hazards for nonsmokers exposed to cigar smoke?

Environmental tobacco smoke (ETS), also known as secondhand or passive smoke, is the smoke released from a lit cigar or cigarette. The ETS from cigars and cigarettes contains many of the same toxins and irritants (such as carbon monoxide, nicotine, hydrogen cyanide, and ammonia), as well as a number of known carcinogens (such as benzene, nitrosamines, vinyl chloride, arsenic, and hydrocarbons). Because cigars contain greater amounts of tobacco than cigarettes, they produce greater amounts of ETS.

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. In addition, the larger size of most cigars (more tobacco) and longer smoking time produces higher exposures to nonsmokers of many toxic compounds (including carbon monoxide, hydrocarbons, ammonia, cadmium, and other substances) than a cigarette. For example, measurements of the carbon monoxide (CO) concentration at a cigar party and a cigar banquet in a restaurant showed indoor CO levels comparable to those measured on a crowded California freeway. Such exposures could place nonsmoking workers attending such events at significantly increased risk for cancer as well as heart and lung diseases.

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