People can become addicted to indoor tanning just as they might to such substances as alcohol or heroin, suggests a study conducted by researchers at the Georgetown Lombardi Comprehensive Cancer Center (GLCCC) published in the journal Annals of Behavioral Medicine.

Indoor tanning has long been criticized by medical professionals for exposing users to gratuitous UV radiation. The cosmetic practice accounts for 400,000 new cases of skin cancer each year, according to the American Academy of Dermatology.

The new finding adds to the growing evidence that tanning can be addictive, and that this has a genetic basis. The GLCCC researchers extracted DNA from salivary samples from 292 white women who described themselves as users of indoor tanning services, including tanning beds, booths and sunlamps. They also gave the women psychological surveys to identify those who were most likely to be addicted to indoor tanning as well as those who showed signs of depression.

Analysis in a genetic lab uncovered a higher incidence of 34 different types of single nucleotide polymorphisms (SNPs)—a variation in DNA—in five genes linked to the development of addictions in the women who used indoor tanning services the most. Women who showed signs of addiction were about twice as likely to have certain SNPs associated with addiction. Women who also displayed depressive symptoms were more than 10 times as likely to have one of those SNPs in particular.

In a statement to Science Daily, lead author Darren Mays, PhD, MPH, said, "By demonstrating that genes in behavioral reward pathways are associated with tanning addiction, we are providing stronger evidence that tanning addiction is a cancer risk behavior in need of intervention.”

Click here to read the abstract.

Click here to read a press release about the study.

Click here to learn more about skin cancer.