Compared to those who have never used it, young people who use indoor tanning have a 69% higher risk of developing a type of skin cancer called basal cell carcinoma (BCC), according to a new study led by researchers from the Yale School of Public Health in the US that was published online on 12 December in the Journal of the American Academy of Dermatology.

The researchers found the risk was strongest among women and went up with every year of using indoor tanning.

A number of studies published recently shows an increase in people, particularly young women, with BCC. The researchers in this study concluded that a quarter of cases of early-onset BCC could be prevented, and as many as 43% among women, if people never used indoor tanning at all.

Senior author Susan T Mayne, professor at the School of Public Health, told the press:

“Indoor tanning was strikingly common in our study of young skin cancer patients, especially in the women, which may partially explain why 70 percent of early-onset BCCs occur in females.”

Mayne said they were also “surprised to find that one-third of our study participants with BCC had already had at least one additional BCC before age 40, which is very alarming as skin cancers increase in frequency with age”.

BCC is the most common type of skin cancer, it rarely spreads or kills, but it can invade surrounding tissue and cause unsightly disfigurement. Most occur on parts of the body that are repeatedly exposed to the sun, such as the head and neck, but there appears to be an increase in cases of them appearing on the torso.

For the study, Mayne and colleagues interviewed 376 patients diagnosed with BCC and 390 controls without BCC who had been diagnosed with minor, benign, skin conditions. All subjects were under 40 years of age. They answered questions about whether they had ever used indoor tanning, and if so, at what age they started, how often they used it, how long did sessions last, the number of burns received as a result of tanning, and the type of tanning machine.

Using statistical tools, they then calculated the odds of developing BCC, using those who had never used indoor tanning machines as the referent group.

The analysis showed that:

  • Ever using an indoor tanning machine was linked to a 69% higher risk of early-onset BCC.
  • This link was stronger among young women, for those who developed more than one BCC, and for those whose BCCs appeared on the torso or extremities.
  • The risk went up in a “dose-dependent” fashion for each of three variables: each year of using indoor tanning, number of overall burns, and burns to biopsy site.
  • 27% of early-onset BCCs, and as many as 43% in women, could be prevented if individuals never used indoor tanning machines.

The researchers conclude:

“Indoor tanning was a strong risk factor for early-onset BCC, particularly among females. Indoor tanning should continue to be targeted by both policy-based and behavioral interventions, as the impact on BCC-associated morbidity may be substantial.”

They say due to some of the study limitations, such as “potential recall bias of indoor tanning by patients and generalizability of the control population”, the results need to be confirmed by further research.

Should these findings be confirmed, they add to recent evidence that indoor tanning is linked to melanoma, a less common but much deadlier form of skin cancer that is also increasing among young women.

First author Leah M. Ferrucci, a postdoctoral fellow at the School of Public Health, said:

“Importantly, indoor tanning is a behavior that individuals can change. In conjunction with the findings on melanoma, our results for BCC indicate that reducing indoor tanning could translate to a meaningful reduction in the incidence of these two types of skin cancer.”

Estimates suggest around 30 million Americans use indoor tanning beds every year, with young women being the most common users.

Written by Catharine Paddock PhD