A new study shows that having at least five blistering sunburns as a teenager is associated with an increased risk of skin cancer later in life, including deadly melanoma.

The study, published in the journal Cancer Epidemiology, Biomarkers & Prevention, showed that people who experienced five or more blistering sunburns between ages 15 and 20 had a 68 percent increased risk of two kinds of skin cancer, basal cell carcinoma and squamous cell carcinoma, as well as an 80 percent higher melanoma risk.

Melanoma is considered the most dangerous kind of skin cancer, killing about 8,790 people each year, according to the Skin Cancer Foundation. While curable if caught early, it becomes harder to treat and can be fatal once it has progressed and spread elsewhere in the body.

Researchers also found an association between ultraviolet radiation exposure and skin cancer. People who were exposed to the most cumulative UV radiation throughout adulthood had a 2.35-fold increased risk of skin basal cell carcinoma, and a 2.53-fold increased risk of skin squamous cell carcinoma.

The study is based on 108,916 Caucasian registered nurses who were part of the Nurses’ Health Study II and who enrolled in the study when they were between ages 25 and 42. At the beginning of the study, they were asked about blistering sunburns they experienced between ages 15 and 20, how many moles they had on their legs, and family history of melanoma. Then, health information was collected from them every two years for approximately 20 years.

By the end of the study, 6,955 people were diagnosed with basal cell carcinoma, 880 were diagnosed with squamous cell carcinoma of the skin, and 779 were diagnosed with melanoma. About one-quarter of all the study participants had had painful blisters during childhood or adolescence, and about one in 10 of all the study participants said they had experienced more than five blistering sunburns between 15 and 20.

“This study adds to a growing body of research indicating that UV radiation exposure early in life through both natural (e.g., sunlight) and artificial (e.g., tanning beds) sources significantly increases the risk of skin cancer,” said Darren Mays, Ph.D., MPH, an assistant professor of oncology at Georgetown Lombardi Comprehensive Cancer Center, who was not involved in the study.

“Although the results show potential differences may exist in the relationships between sun exposure and cancer risk for different types of skin cancer, from a primary prevention standpoint the message to be gleaned from this seems fairly clear: Preventing harmful UV exposure early in life plays a critical role in reducing the risks of melanoma and non-melanoma skin cancer in the future.”