A new health study shows that Caucasian women who suffer at least five sunburns before the age of 20 have increased risk of developing melanoma, the fatal skin cancer.

For the study, researchers examined around 20 years of data about 108,916 Caucasian registered nurses, who were a part of the Nurses' Health Study II. The participants were aged between 25 and 42 at the time of the study. They completed an initial interview that measured risk factors for skin cancer, such as frequency of sunburns, the number of moles on the legs and family history. The information was updated every two years.

The researchers noted that nearly 24 percent of the people had painful blisters due to the sun when they were children or adolescents. About 10 percent had more than five blistering sunburns when they were aged between 15 and 20. Overall, 6,955 people were diagnosed with basal cell carcinoma, 880 with squamous cell carcinoma and 779 with melanoma and 445 of the patients with melanoma had invasive cancer.

The study results showed that participants who experienced at least five blistering sunburns when they were 15 to 20 years old had a 68 percent more risk for BCC and SCC. The risk of developing melanoma shot up 80 percent. Furthermore, the researchers found that those exposed to the highest levels of ultraviolet (UV) radiation had a 2.35-fold increased risk of getting BCC and a 2.53-fold increased risk of developing SCC. However, they did not have an increased risk of developing melanoma.

"Our results suggest that sun exposures in both early life and adulthood were predictive of nonmelanoma skin cancers, whereas melanoma risk was predominantly associated with sun exposure in early life in a cohort of young women," said Abrar A. Qureshi, M.D., MPH, professor and chair of the Department of Dermatology at Warren Alpert Medical School of the Brown University and Rhode Island Hospital in Providence.

"Pattern of sun exposure was not uniformly associated with the risk for all the three main skin cancers we see in the United States, suggesting that there are some differences in the pathophysiology of these skin cancers," said Qureshi in a press release. "An individual's risk of developing skin cancer depends on both host and environmental risk factors. Persons with high host-risk traits, such as red hair color, higher number of moles, and high sunburn susceptibility, should pay more attention to avoid excessive sun exposure, especially early in life."

A recent study found a natural way of keeping sun safe during summers. The researchers said people who eat a quarter cup of tomato paste daily experienced lower incidences of sunburn and increased their skin's natural SPF by as much as a third.

The current study was published in the American Association for Cancer Research journal, Cancer Epidemiology, Biomarkers & Prevention.