Evidence Doesn’t Indicate Benefit to Health

About low-tar cigarettes.

Millions of Americans smoke "low-tar," "mild," or "light" cigarettes, believing those cigarettes to be less harmful than other cigarettes. In a new monograph from the National Cancer Institute (NCI) titled Risks Associated with Smoking Cigarettes with Low Machine-Measured Yields of Tar and Nicotine*, national scientific experts conclude that evidence does not indicate a benefit to public health from changes in cigarette design and manufacturing over the last 50 years.

"This report was made possible by the work and cooperation of scientists throughout the country," said Scott Leischow, Ph.D., chief of the NCI Tobacco Control Research Branch. "The monograph clearly demonstrates that people who switch to low-tar or light cigarettes from regular cigarettes are likely to inhale the same amount of cancer-causing toxins and they remain at high risk for developing smoking-related cancers and other diseases." This monograph is the 13^th volume in NCI's Smoking and Tobacco Control Monograph Series, which began in 1991.

Public Health Effects

Epidemiologic studies (studies that examine the relationship of risk factors to health and disease) in the late 1960s and 1970s found that smokers of lower-tar or filtered cigarettes had somewhat lower lung cancer risks than smokers of other cigarettes. This finding was particularly noteworthy because smokers in these studies had been smoking the reduced-yield cigarettes for only a relatively short period of time. It was predicted that as more smokers used lower yield products for longer periods of time, a greater benefit would occur and national lung cancer death rates would fall.

Unfortunately, these reductions have not been seen. Even as the popularity of lower- yield cigarettes grew - 97 percent of the cigarettes now sold in the United States are filtered cigarettes - lung cancer rates continued to rise until the early 1990s. The monograph demonstrates that the overall decline that has been seen since the 1990s can be attributed to the decrease in smoking prevalence, and not to changes in cigarette design.

The new monograph reviews published literature on death rates in the U.S. and the United Kingdom which also demonstrated an increase - rather than a decrease - in smoking risks over a period when machine-measured yields of tar and nicotine were declining. Two studies conducted by the American Cancer Society more than 20 years apart found that, despite the large reduction in machine-measured tar yield over this period, smokers in the later study had an increased risk of lung cancer. This increase was seen even when differences in the number of cigarettes smoked per day and duration of smoking were factored into the analysis. The monograph clearly demonstrates that the expected reduction in lung cancer risk offered by the early epidemiologic studies has not been seen in national lung cancer death rate trends.

Surveys have indicated that among the estimated 47 million adults who smoke in the United States, people who are most concerned about smoking risks or are most interested in quitting use brands labeled "light" or "ultra-light." Unfortunately, the monograph finds that choosing lower-yield cigarettes is not likely to reduce tar intake and resulting disease risks. Furthermore, marketing and promotion of reduced yield products may delay genuine attempts to quit. There is no evidence that switching to light or ultra-light cigarettes actually assists smokers in quitting.

According to David M. Burns, M.D., senior scientific editor of the monograph and a professor at the University of California, San Diego School of Medicine, "The take-home message of this report is that the only proven way to reduce the disease risks associated with smoking is to quit."