The use of high-factor sunscreen can decrease the risk of developing melanoma, according to a study published recently in the Journal of Clinical Oncology.
The study, “Sunscreen Use and Subsequent Melanoma Risk: A Population-Based Cohort Study,” published by the Department of Biostatistics with the Faculty of Medicine at the University of Oslo, reveals that using high-factor sunscreen instead of low-factor sunscreen can lead to a reduction of melanoma risk by more than 30%.
The research team used data collected from a Norwegian Women and Cancer (NOWAC) study and merged with data from the Cancer Registry of Norway. This allowed them to follow more than 140,000 Norwegian women, ages 40 to 75 years, for an average of 10 years. To assess the melanoma risk associated with use of sunscreen, participants were asked, among other things, to report if they had used sunscreen and its precise sun protection factor.
Sunscreen users reported more sunburn, more sunbathing vacations, and use of tanning beds when compared to those who never used sunscreen, the study found. As a result, non-sunscreen users presented a lower risk of melanoma than those who used low-factor sunscreen.
This is in line with previous results demonstrating that sunscreen users had a slightly increased risk of melanoma, compared to non-users.
“The explanation for this paradox is that some people use sunscreen to prolong sun exposure and acquire suntan. Moreover, many people don’t apply the proper amount of sunscreen, forget to reapply and missed to apply on all exposed areas resulting in sunburn and increased risk of melanoma,” Reza Ghiasvand, the study lead author, said in a press release.
To control for this confounding factor, researchers analyzed sunscreen users based on the sun protection factor they usually used. They found that those who used higher factor sunscreen were less likely to develop melanoma.
“We found that those who used sunscreen with a factor higher than 15 had a 33% lower risk of melanoma compared with those using sunscreen with a low factor,” said Ghiasvand.
Also, according to researchers’ estimates, the use of sunscreen with a factor higher than SPF 15 by all women aged 40 to 75 years could lead to an 18% decrease in melanoma incidence in approximately 10 years.