Researchers from City of Hope National Medical Center in Duarte, Calif., said that UVB light is more harmful to skin because the body is less able to repair the DNA damage it causes than the damage caused by UVA light.
The scientists exposed three sets of cells to UVA light, UVB light and simulated sunlight. They compared these cells to an unexposed control group to analyze how well these cells were able to repair the damage.
The study, published in the July issue of The Federation of American Societies for Experimental Biology Journal, found cells were more easily able to repair the damage caused by the UVA light. However, scientists and public health experts caution that UVA light can and does cause serious damage that can and does lead to skin cancer.
"We know that sunlight causes skin cancer and that breakdown of the ozone layer exposes us to ever more ultraviolet radiation," Dr. Gerald Weissmann, editor in chief of The FASEB Journal said in a statement. "This work tells us that both forms of UVA and UVB in sunlight cause damage to DNA."