A new study determined that African Americans may be more predisposed to developing nicotine addiction than those with paler skin. The research also reveals that obtained darker skin (that obtained from prolonged sun exposure, not through genetics) is especially linked with tobacco addiction. Researchers from Pennsylvania State University also said they identified a statistical correlation between the frequency of smoking and skin color.
“African Americans are known to have a more difficult time quitting and suffer from more tobacco-related diseases. By addressing the connection between biological aspects of skin color and tobacco use, this has global implications for all groups, especially to populations with high levels of UV radiation,” explained Penn State medical sociologist Gary King, lead author of the paper.
The investigation reveals that the main reason behind this predisposition is the pigment melanin, which determines the overall color of the skin. King said that the chemical appears to have a special affinity towards nicotine, as it binds to it solidly. The connections are not easily broken, so the nicotine, together with other harmful substances in tobacco, accumulates in organs such as the heart, lungs, liver, and brain, where they can cause severe diseases such as cancer.
In humans, melanin can appear in two ways: either by genetic causes where genes are passed on from mother to child, or by prolonged exposure to UV radiation or even cosmetic tanning beds. Either way, King said, there is no distinguishable difference between the two type of melanin, and their chemical affinity towards nicotine is exactly the same.
The researchers also learned that various regions of the body are related to the chances that a darker-skinned person has of smoking more frequently and becoming more addicted to nicotine. Darkness on the forehead exhibited the strongest link, whereas darker skin on the forearm showed no statistical correlation to nicotine addiction.
King said he is still unsure of how this mechanism works, but he hypothesizes that dependency might be given by the fact that darker-skinned people constantly carry a small amount of nicotine in their bloodstream, even some time after they quit smoking.