May 10, 2009

Skin color linked to nicotine dependence

Higher concentrations of melanin -- the color pigment in skin and hair -- may indicate increased susceptibility to nicotine dependence, U.S. researchers say.

We have found that the concentration of melanin is directly related to the number of cigarettes smoked daily, levels of nicotine dependence, and nicotine exposure among African Americans, Gary King of Pennsylvania State University says in a statement.

The researchers recruited 150 adult African-American smokers from three sites in inner city Harrisburg, Pa., during summer 2007. Participants provided researchers with the average number of cigarettes smoked each day and answered a questionnaire that measured nicotine dependence.

Researchers also measured the smokers' cotinine levels -- a metabolic byproduct of nicotine that can be used as a biomarker for tobacco use.

The total amount of melanin acquired genetically -- plus the amount from the tanning effect of sunlight -- is significantly linked to the number of cigarettes smoked per day, the study said.

However, the researchers caution that additional studies with larger samples of smokers with varying levels of skin pigmentation will be required to provide a clearer picture.

The finding is scheduled to be published in the June issue of the journal Pharmacology, Biochemistry and Behavior.