Indoor tanning increases the risk of skin cancer, which is the most common type. According to the Centers for Disease Control and Prevention, indoor tanning is not as popular as it once was, but around 8 million adults still use indoor tanning machines every year. Now scientists have investigated whether some people might be genetically predisposed to become addicted to tanning.
The researchers found that increased symptoms of depression as well as changes in a gene that is related to dopamine - a molecule involved in reward pathways, can impact tanning addiction in young white women. The work has been reported in the Annals of Behavioral Medicine.
"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," said the lead study author Darren Mays, PhD, MPH, an associate professor of oncology and member of the Cancer Prevention and Control Program at Georgetown Lombardi. "This finding adds to a growing body of evidence from animal studies and neuroimaging studies that have been done in humans."
This work assessed genetic data and surveys from 292 white, non-Hispanic, Washington DC-area female residents aged 18 to 30 who use sunlamps or tanning beds. Small changes in individual base pairs in genes are common, and if more than one percent of the population carries one of those small changes, it's designated as a single nucleotide polymorphism or SNP (pronounced snip). The investigators looked at five SNPs in their cohort, which relate to molecules that are involved in rewarding addicting behaviors.
For two SNPs, there was a roughly two-fold increase in the odds of indoor tanning addiction for those carrying the modifications. For SNPs that may increase tanning addiction risk due to depression, the risk was raised ten-fold if there were changes in a SNP called rs4648318, and modifications to the rs4648318 SNP caused a thirteen-fold increase in tanning addiction risk.
Learn about the dangers posed by tanning beds from this video by Mayo Clinic.
This information might be useful in screens that identify people who are at risk of becoming addicted to an activity that causes cancer. While most of the ultraviolet rays that we're exposed to come from the sun, indoor tanning is blamed for a ten percent increase in skin cancer cases.
Another study that Mays is getting started on will explore the use of text messages as a preventative tool that can help addicts quit tanning.
"This grant will enable us to test behavioral interventions in young women who are addicted to indoor tanning," Mays said. "We have used text messaging to intervene in other behaviors and have found that the personalized conversation we can deliver through this medium can help people take steps to quit."