Led by researchers at the University of Sydney, Australia, the study is the first to look at how using sunscreen in childhood could affect the melanoma risk for Australian adults aged 18 to 40 years.
The team looked at data on sunscreen use collected from interviews with 603 melanoma patients and 1,088 control participants.
The results showed that regularly using sunscreen in childhood and adulthood was significantly associated with a decreased risk of melanoma among young adults age 18 to 40, with the risk reduced by 35 to 40 per cent for regular sunscreen users compared to those who rarely used it.
The researchers found that sex, age, ancestry, educational level, skin pigmentation, and sunburn were also factors associated with sunscreen use.
Regular users of sunscreen were more likely to be female, younger, of British or northern European ancestry, have a higher education level, lighter skin pigmentation, and a strong history of blistering sunburn, whereas participants were who were male, older, less educated, or had skin that was darker or more resistant to sunburn were less likely to use sunscreen.
"Despite sunscreen being widely available and recommended for sun protection, optimizing the use of sunscreens remains a challenge and controversies continue to surround its use," commented lead researcher Associate Professor Anne Cust.
"This study confirms that sunscreen is an effective form of sun protection and reduces the risk of developing melanoma as a young adult. Sunscreen should be applied regularly during childhood and throughout adulthood whenever the UV Index is 3 or above, to reduce risk of developing melanoma and other skin cancers."
"Some population subgroups such as people with sun-sensitive skin or with many moles might get a stronger benefit from using sunscreen."
Melanoma is the most common cancer diagnosed in Australian men aged 25 to 49 years and second most common cancer in women aged 25 to 49 years, after breast cancer.
Approximately two in three Australians will be diagnosed with melanoma or other types of skin cancer by the time they are 70 years old.
The results were published online in the journal JAMA Dermatology.
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