We sometimes are asked if cigars are safer than cigarettes. There has been more study into the health consequences of cigarette smoking, but there is enough strong evidence about the health problems caused by cigar smoking to answer no, cigar smoking is a very substantial risk to health.
The smoke from cigars contains the same toxic chemicals as the smoke from a cigarette. Compounds in the smoke can cause cancer, heart disease, lung diseases as well as oral and dental disease, which has been linked specifically to cigar smoking. Second hand smoke from cigars increases the risk for childhood asthma, ear infections, and upper and lower respiratory infections in children.
LIke cigarettes cigars contain nicotine, the addictive ingredient in tobacco. A single full size cigar can contain as much nicotine as does a pack of cigarette. The nicotine from cigars is usually absorbed through the lining of the mouth, which can certainly cause addiction. Switching from cigarette smoking to cigar smoking can be particularly harmful because you might inhale cigar smoke the way you inhaled cigarette smoke and possibly ingest much more nicotine than from a cigarette and many more toxins than from a single cigarette.
Although the specific health effects from a single occasional cigar aren't so clear, there is no safe form of tobacco, and the only safe level of cigar smoking is none at all.