A new study on sunscreen finds that its health benefits may be better than advertised.

Dermatologists have long promoted sunscreen for preventing the sun’s ultraviolet rays from aging the skin and causing skin cancer, but sunblock with as little as SPF30 may also slash the risk of melanoma, the deadliest form of skin cancer, according to an Ohio State University statement.

Scientists hadn’t been able to test whether sunscreens prevented melanoma in the past, because sunscreens are often manufactured as cosmetics and therefore tested on volunteers or synthetic skin models. However, scientists at Ohio State were able to develop a mouse model that will let them test for the ability of sunscreen to prevent melanoma as well as burns.

Melanoma is the most dangerous type of skin cancer, killing 10,000 people every year and sickening 76,000 annually.

Melanomas appeared much more rapidly and with more tumors when mice exposed to a single dose of ultraviolet light per day after the addition of a chemical called 4-hydroxytamoxifen.

Then, researchers tested numerous SPF30 sunscreens, and found that all delayed the onset of melanoma.

“Over the past 40 years, the melanoma incidence rate has consistently increased in the United States,”Christin Burd, PhD, an assistant professor in the Department of Molecular Genetics and the Department of Molecular Virology, Immunology & Medical Genetics, said in the statement. “Sunscreens are known to prevent skin from burning when exposed to UV sunlight, which is a major risk factor for melanoma. However, it has not been possible to test whether sunscreens prevent melanoma, because these are generally manufactured as cosmetics and tested in human volunteers or synthetic skin models.

“We have developed a mouse model that allows us to test the ability of a sunscreen to not only prevent burns but also to prevent melanoma,” added Burd. “This is a remarkable accomplishment. We hope that this model will lead to breakthroughs in melanoma prevention.”