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Nicotine Replacement Therapy Helps Reduce Smoking Temporarily, But Reduction Alone May Not Improve Health

En Español (Spanish Version)

About 36 million Americans smoke cigarettes on a daily basis. While the profound health risks associated with smoking are well-known, so too is the difficulty of quitting. Annual quit rates are less than 4%. Researchers are investigating methods that may lessen cigarettes’ toxic effects among people unable or unwilling to quit, such as reducing the number of cigarettes smoked per day.

Two British researchers carefully analyzed a number of trials designed to reduce daily cigarette use among smokers with the help of nicotine replacement therapy (NRT). Their findings, in the July 18, 2007 Cochrane Database of Systematic Reviews 2007 , showed that smokers using NRT were twice as likely to cut their daily use of cigarettes by 50% and more likely to quit, than those given placebo. However, few smokers maintained the cigarette reduction over time, and blood levels of carbon monoxide did not drop significantly.

About the Study

British researchers scoured the Cochrane Tobacco Addiction Group Specialised Register for controlled trials designed to assist smokers in cutting down on—but not quitting—cigarettes. Data from eight trials that used NRT to reduce smoking were analyzed together. Researchers compared the number of cigarettes smoked per day, blood levels of carbon monoxide (a biomarker for tobacco exposure), and smoking cessation rates between the groups receiving NRT and those that did not.

Among the 3,273 smokers in the meta-analysis, those who used NRT were twice as likely to cut their daily use of cigarettes by 50% than those given placebo. However, few smokers maintained this lower level of smoking over time. Carbon monoxide levels were lower with NRT, although not significantly so, making the long-term health benefits of cutting down on cigarettes unclear. NRT also increased the rate of quitting, from 1%-3% in the placebo groups to 6%-9% in the NRT groups.

These findings are limited by the different methods used in the eight trials. In addition, measuring the number of cigarettes may not be a true marker of toxin exposure as it does not account for potential “compensatory smoking,” in which a smoker strives to obtain the maximum amount of nicotine from each cigarette.

How Does This Affect You?

Are efforts to reduce smoking worthwhile? Yes, but cigarette reduction should be viewed as a means to an end—complete cessation—not an end in itself. The health burden of smoking is too great and the benefits of cutting back are too small to make cigarette reduction a satisfactory end point. In addition, the small changes in carbon monoxide levels in this study suggest that reducing daily cigarettes may not be enough to produce clinically significant health improvements.

The grip of a nicotine addiction is remarkably strong and breaking this grip is no small matter. There are many methods available to help smokers quit including NRT, prescription drugs, and support groups. If you smoke, talk with your doctor about getting started on the method that’s right for you.




  • Cigarette smoking among adults—United States 2004. Morbidity and Mortality Weekly Report . 2005;54:1121-1124.
  • Stead LF, Lancaster T. Interventions to reduce harm from continued tobacco use. Cochrane Database of Systematic Reviews 2007, Issue 3. Art. No.: CD005231. DOI: 10.1002/14651858.CD005231.pub2.

Last reviewed October 2007 by Richard Glickman-Simon, MD

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