Indoor tanning beds cause over 170,000 cases of non-melanoma skin cancer in the United States every year, according to a new study conducted by researchers at UC San Francisco.
"The numbers are striking--hundreds of thousands of cancers each year are attributed to tanning beds,'' Dr. Eleni Linos, assistant professor of dermatology at UCSF and senior author of the study, said in a statement. "This creates a huge opportunity for cancer prevention.''
The study analyzed more than 80,000 cases of non-melanoma skin cancer stretching back to 1977, finding that people who used tanning beds are 67 percent more likely to develop squamous cell carcinoma and 29 percent more likely to develop basal cell carcinoma than those who don't. Drawing from a trio of prior reports that also examined the ages of tanners, the study noted an even larger cancer risk for people who used the beds while under the age of 25.
While non-malignant on their own, U.S. Health News explains that both basal cell skin cancer and squamous cell carcinomas can spread to other parts of the body, such as bones or lymph nodes, where they can become fatal.
A 2007 study out of the University of Iowa's Department of Dermatology found that exposure to tanning beds also significantly increases the risk of developing malignant melanoma, especially in women over age 45.
"Indoor tanning is associated with a significantly increased risk of both basal and squamous cell skin cancer," concluded the USCF study's authors. "These findings contribute to the growing body of evidence on the harms of indoor tanning and support public health campaigns and regulation to reduce exposure to this carcinogen."
That suggests indoor tanning is responsible for about 5% of non-melanoma skin cancers, the most commonly diagnosed cancers in the USA, says Thomas Glynn, director of cancer science and trends at the American Cancer Society. Non-melanoma skin cancers strike about one in five Americans during their lifetime, including 30% of whites, Linos says. Those who started tanning indoors before age 25 had the highest skin cancer risk, according to the analysis, which included 12 studies involving 80,000 people in six countries.
The authors noted that fair-skinned people, a group thought to be more genetically prone to skin cancer, are also more likely to utilize tanning beds. However, researchers dismissed that line of reasoning as a link between tanning beds and cancer because most of the studies they analyzed controlled for skin type and sun sensitivity.
In recent years, governments around the world have begun to crack down on indoor tanning. President Obama's Affordable Care Act imposed a ten percent tax on tanning salons both as a revenue generation measure and as a way to discourage the practice.
Last year, California became the first state to ban tanning bed use by people under the age of 18. In May, the state of New York followed suit with a similar prohibition. Thirty other states require some form of parental consent before allowing minors to use tanning beds.
A study conducted earlier this year by the Center for Disease Control estimated that one-third of white, American women have used tanning beds.