It's not that menthol cigarettes are more dangerous, it's just that — for some reason — they appear to be harder to give up than regular cigarettes.

Cigarette smoking causes about 440,000 deaths in the United States each year. African Americans tend to smoke less than European Americans, but they have disproportionately high rates of cancer, cardiovascular disease and other smoking-related illnesses.

Could menthol be the reason?

"For a variety of historical and cultural reasons, including targeted advertising by the tobacco industry, African American smokers are much more likely to smoke menthol cigarettes than European American smokers (approximately 70 percent vs. 30 percent)," according to the authors of a new report.

Mark J. Pletcher, M.D., M.P.H., University of California, San Francisco, and colleagues compared the effects of menthol and non-menthol cigarettes in 1,535 smokers. They measured the association between exposure to menthol cigarettes and quitting smoking cessation; coronary calcification, an early sign of coronary artery disease; and change in lung function over a 10-year period.

As reported in the September 25, 2006 issue of Archives of Internal Medicine, the authors report that those who smoked menthol cigarettes in 1985 were more likely still to be smoking at follow-up examinations years later. In 2000, for example, 69 percent were still smokers vs. 54 percent of non-menthol smokers. Most of this difference was explained by the fact that African Americans were both more likely to smoke menthols and less likely to quit smoking.

"Among smokers who tried to quit, menthol seemed unrelated to quitting, but menthol was associated with a lower likelihood of trying to quit in the first place," the authors write. Analyzing the data over time, they found that menthol smokers were almost twice as likely to relapse after quitting and also were less likely to stop for a sustained period of time. Both coronary calcification and a decline in lung function over 10 years were associated with the number of cigarettes smoked, but whether the cigarettes were menthol or not did not appear to make a difference.

"Mentholation of cigarettes does not seem to explain disparities in ischemic heart disease and obstructive pulmonary disease between African Americans and European Americans in the United States but may partially explain lower rates of smoking cessation among African American smokers," the authors conclude. "It is possible, therefore, that switching from menthol cigarettes to non-menthol cigarettes might facilitate subsequent quitting, especially in African Americans."