Although national and international officials have long agreed that indoor tanning is a top risk factor for cancer and a number of skin issues, some studies still suggest that this practice has benefits. But those findings are misleading?
According to 2015 statistics — the latest available— around 3.5 per cent of adults in the U.S. had used indoor tanning facilities in the past year.
The Centers for Disease Control and Prevention (CDC) describes indoor tanning as the practice of”[ u]sing a tanning bed, table, sunbed, or sunlamp to darken[ the] skin.”
Both the CDC and the World Health Organization (WHO) warn that the strong ultraviolet (UV) rays people expose themselves to when indoor tanning can cause skin cancer. Consequently, they warn people to avoid tanning beds and other similar devices.
So why do a lot of studies still suggest that tanning indoors is safe and even beneficial?
A new review of the indoor tanning literature conducted by researchers at the Stanford University School of Medicine in California reveals that work that has received funding from the tanning industry is generally leaning to the side of positive results.
“Financially related research with the indoor tanning industry were much more likely to discuss perceived benefits of indoor tanning and downplay the harms,” says study co-author Prof. Eleni Linos.
“The association is quite striking. We need scientific data to be independent of industry influence. I am concerned that funding sources may influence the conclusions of these papers.”
– Prof. Eleni Linos
Industry funding may skew findings
The writers have looked at 691 articles addressing indoor tanning for the study, which appears in BMJ. These included both empirical research, such as original research, as well as non-empirical research, such as editorials.
Of those reports, 50 admitted the indoor tanning industry had earned some form of financial support.
Positive conclusions about indoor tanning were reached by 78 percent amongst the industry backed studies. Similar findings were reported by only 4 per cent of independent research that had not received funding from industry.
One reviewer first listed all of the relevant articles to perform this analysis before eliminating any information regarding conflicts of interest and funding.
Instead, two of the other investigators were given the job of assessing and rating each article, using a five-point scale that ranged from strongly in favor of indoor tanning to strongly against it.
Finally, the researchers went back to see which studies the industry had financially backed and which ones had not. We could then assess how many positive conclusions about this procedure had been drawn by each form, and how many had highlighted the negatives.
“Although the number of papers with financial ties to the tanning industry was relatively small, if used in legal challenges and promotional material, these papers could have wide traction,” notes review co-author Meghan Halley, Ph.D.
“Tanners receiving these messages may develop a misperception of benefits,” she adds.
The research team also encourages anyone who relies on specialized studies for indoor tanning safety information to evaluate with a critical eye their accuracy and to test whether or not those studies have earned any funding from industry stakeholders.
“This is the first research to investigate conflicts of interest in indoor tanning literature and it confirms what has been said about the scientific impact of the tobacco and sugar industries,” says Prof. Linos.
“When evaluating the evidence relating to the risks and benefits of indoor tanning, researchers, public health experts and members of the general public should be aware of and account for industry funding,” she stresses.
