A study [3] of nearly 1,700 smokers attending a quit-smoking clinic at the University of Medicine and Dentistry of New Jersey (UMDNJ) found that menthol [4] cigarette smokers have a harder time quitting than people who smoke non-menthol cigarettes, even when the menthol smokers smoke fewer cigarettes per day. Jonathan Foulds, Director of the Tobacco Dependence Program at UMDNJ said, "More than 80 percent of the African American smokers [5] attending our clinic smoke menthols, and they have half the quit rate of African Americans who smoke non-menthol cigarettes." Researchers believe that menthol's cooling effects make it easier to inhale more nicotine from each cigarette and thus obtain a more potent and addictive dose of the drug. Epidemiological studies show a significantly higher use of mentholated cigarettes, and consequently smoking-related cancers, among African Americans than in the white population of the United States.