Metabolic and cardiovascular effects of smokeless tobacco.

The nation's largest cigarette companies are selling more smokeless tobacco (ST) products as more cities and states pass smoke-free laws. ST use is already common and is expected to get more popular as a result of these recent changes. Unfortunately, the medical and public knowledge of its risks is inadequate. The literature on the cardiovascular side effects of ST is scant, and there are many controversies associated with its use, for various reasons. Study findings show that ST may modestly increase cardiovascular mortality and produces transient changes in heart rate and blood pressure; however, it does not increase the risk of atherosclerosis or myocardial infarction. The association between ST and diabetes, lipoproteins, and stroke is less clear. Quitting ST causes weight gain, but less so than smoking. Although ST appears to be associated with less cardiovascular risk than smoking, nicotine replacement therapy is a safer and more controlled substitute for smoking than ST; however, ST can be considered in high-risk smokers in whom medicinal nicotine replacement therapy has failed.