Early in 2014, the United States Food and Drug Administration moved tanning lamps into a new category of “moderately harmful” medical devices, and with good reason, researchers say.

In a review of the evidence that indoor tanning does damage, and has no health benefits, the study authors point out that the new rules will force device manufacturers and salons to do more to protect users.

"We feel that this is a very positive move by the FDA," said Dr. Henry Lim, chairman of dermatology at Henry Ford Medical Center in Detroit, Michigan, and senior author of the review. "There is a lot of evidence that early and frequent use of tanning beds increases the risk of skin cancer."

Among the new requirements is that all sunlamps have a “black box warning label” that says they shouldn’t be used by people under age 18, Lim's team writes.

This is the strictest warning that the FDA puts on products, and it is used when there is reasonable evidence of a serious hazard, Kim and his coauthors point out in a paper released online November 11 in the Journal of the American Academy of Dermatology.

"The new regulations don't ban the use of tanning beds for children and teens," Lim cautioned. "That will be up to the discretion of the salons."

However, the FDA guidelines will probably prompt more states to enact legislation, Lim told Reuters Health. Currently, 41 states including the District of Columbia have some type of regulation in place, such as requiring parental consent.

Several states have completely banned indoor tanning for minors, as has Brazil. In July, Hawaii became the 10th state to do so, joining Vermont, California, Illinois, Louisiana, Minnesota, Oregon, Nevada, Texas and Washington.

"Earlier exposure to indoor tanning is associated with a greater risk for developing basal cell carcinoma at a young age," said Margaret Karagas, director of the Children's Environmental Health and Disease Prevention Research Center at Dartmouth University in Hanover, New Hampshire.

"The new FDA regulations reinforce the science that teens and young adults may be especially vulnerable to developing skin cancer if they use tanning beds," said Karagas. She was not involved in the review but recently published a study showing that a high proportion of patients with early-onset basal cell carcinoma had used indoor tanning.

However, Lim’s team also points to studies that found people who were exposed to tanning beds before the age of 35 years had a significantly higher risk of developing melanoma.

In their report, the researchers review the science of how skin’s exposure to ultraviolet light from tanning beds, or the sun, causes the DNA damage that can lead to cancer. “Tanning is a clinical manifestation of cellular stress,” they emphasize.

“Moreover, the common misconception that tanned skin offers protection from future UV radiation is proved false as there is no biochemical mechanism restricting further mutagenesis upon subsequent exposure,” they write.

The study team covers evidence that use of tanning beds can be addictive in the same way as a drug. And they point out that the devices primarily emit UV-A light, which is less effective at inducing skin to make vitamin D than UV-B, so there’s no argument for a health benefit there.

It’s uncertain how much of an effect these new regulations will have on tanning bed users, Lim’s team says.

Nearly 30 million Americans use tanning beds each year, and more than 2 million of them are teenagers, according to the American Academy of Dermatology.

And about 70 percent of users are girls and young women between the ages of 16 and 29 years old.

These data are the most troubling, they write, since young women are known to be the most at-risk population for developing melanoma associated with the use of tanning beds.

"Pediatricians should counsel parents and patients about the risks of using tanning beds," Karagas said.

Lim’s team hopes their review will be used by doctors as a resource for doing just that.