Although tanning has decreased among high school students, about 20 percent of females engaged in indoor tanning at least once during 2013 and about 10 percent of girls frequently engaged in the practice by using an indoor tanning device 10 or more times during the year, according to a recent study.

Indoor tanning increases the risk of skin cancer, especially among frequent users who started tanning at a young age, according to the study background.

For the study, Gery P. Guy Jr. of the U.S. Centers for Disease Control and Prevention and colleagues estimated indoor tanning trends among high school students using data from the 2009, 2011 and 2013 national Youth Risk Behavior Surveys.

Indoor tanning was defined as using a tanning device (e.g., sunlamp, sunbed, tanning booth, excluding a spray-on tan) at least once during the 12 months before each survey period and frequent indoor tanning was using a tanning device more than 10 times during the same period. The surveys included more than 16,410 students in 2009, 15,425 in 2011 and 13,583 in 2013; overall response rates were 71 percent, 71 percent and 68 percent, respectively.

Results indicate 20.2 percent of female high school students engaged in indoor tanning in 2013 and 10.3 percent engaged in frequent indoor tanning. Indoor tanning was most common among non-Hispanic white girls. Among male students, 5.3 percent engaged in indoor tanning and 2 percent engaged in frequent indoor tanning.

From 2009 to 2013, tanning decreased among female students (from 25.4 percent to 20.2 percent), among non-Hispanic white girls (from 37.4 percent to 30.7 percent) and among non-Hispanic black male students (from 6.1 percent to 3.2 percent), the results shows.

"These decreases in indoor tanning may be partly attributable to increased awareness of its harms. Despite these reductions, indoor tanning remains common among youth," researchers concluded.

The findings are detailed in JAMA Dermatology.