A study of 1,700 smokers concludes that those who smoke menthol cigarettes have more difficulty quitting, possibly because they take in more nicotine and carbon monoxide than smokers of other types of cigarettes.

The study from the University of Medicine and Dentistry of New Jersey found that smokers of menthol cigarettes -- notably blacks and Latinos -- had a harder time quitting even though they smoked fewer cigarettes per day.

"These results build on growing evidence suggesting that menthol is not a neutral flavoring in cigarettes," said Jonathan Foulds, director of the university's Tobacco Dependence Program. "It masks the harshness of the nicotine and toxins, affects the way the cigarette is smoked and makes it more deadly and addictive.²

Researchers believe that the cooling effect of menthol makes it easier to inhale more smoke and get a larger nicotine dose. Menthol cigarettes have been heavily marketed in minority communities, and researchers speculated that tobacco companies target poor young blacks and Latinos because they can become addicted even when smoking fewer cigarettes.

"More than 80 percent of the African American smokers attending our clinic smoke menthols, and they have half the quit rate of African Americans who smoke non-menthol cigarettes," noted Foulds. African-Americans also have much higher rates of lung cancer, he added.

The FDA tobacco regulation bill now working through Congress would ban most cigarette flavorings but still allow sales of menthol cigarettes.

The findings were published online ahead of print in the International Journal of Clinical Practice.