Baz Luhrmann preached the importance of sunscreen to the ladies and gentlemen of the class of ’99 (and everyone else who listened to the radio in the late ‘90s). Mr. Luhrmann told us the “long-term benefits of sunscreen have been proven by scientists” and he was correct(-ish).
While studies have shown that sunscreen use reduces the risk of both nonmelanoma and melanoma skin cancers (see more details below), some experts question the strength of the scientific evidence supporting this claim. Even the National Cancer Institute (NCI) acknowledges that it is “not known” if sunscreen reduces the risk of skin cancers stating “not enough studies have been done to prove this.” But, this does not mean sunscreen is not beneficial, particularly from preventing sunburn which could indirectly incrase cancer risk.
Even though questions regarding the direct links between skin cancer prevention and sunscreen revolve primarily around a lack of rigorous and robust prospective studies, many organizations providing health care recommendations still encourage the use of sunscreen and skin protection. In addition to the NCI, the Centers for Disease Control (CDC), the American Academy of Dermatology Association (AAD), the American Cancer Society (ACS), and the Food and Drug Administration (FDA) all recommend sunscreen use.
Another challenge directly correlating sunscreen to skin cancer prevention lies in the diversity of many different types of skin cancer. Skin cancer is not a generic malignancy, and in fact, several subtypes of skin cancer exist.
The two most frequently diagnosed skin cancers, basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), rarely metastasize. Oncologists can treat BCC and SCC, sometimes called nonmelanoma skin cancers, effectively in most cases resulting in a favorable statistic: only about 2,000 people in the US die from these malignancies annually.
Compared to nonmelanoma skin cancers, melanoma can become much more serious, especially when diagnosed late. The ACS estimates almost 100,000 new cases of melanoma in 2023. While localized cases of melanoma have a greater than 99% survival rate, only about 32% of patients diagnosed with distantly spread melanoma will survive five years after diagnosis.
Fortunately, the link between sunburn and skin cancer is far less nuanced. A history of severe sunburns increases an individual’s risk of melanoma. One study showed that five sunburns, occurring at any age, doubled melanoma risk. So, since sunscreen can certainly prevent sunburn, it remains an important tool capable of protecting the skin.
Overall, sunscreen provides a relatively low risk approach to preventing skin damage, including sunburn, that could lead to skin cancer. The sun also provides an essential source of vitamin D, needed to support bone density, so some sun exposure is beneficial. Just like evidence definitely linking skin cancer risk and sunscreen, the links between sunscreen and vitamin D remain nuanced due in part to limited long-term prospective studies and potential differences among sun protection factors (SPF).
Each year the National Council on Skin Cancer Prevention (NCSCP) recognizes “Don’t Fry Day” on the Friday before Memorial Day. As Memorial Day weekend serves as the “unofficial start of summer” for many, Don’t Fry Day presents an opportune time to educate, advocate, and raise awareness about skin cancer prevention. The NCSCP website provides tools and resources, such as videos, kids’ activities, and sun safety tips, to help everyone enjoy the sun safely!
Sources: Lancet, J Clin Oncol, J Am Acad Dermatol, Br J Dermatol
