Dec. 15, 2003 -- Using a sunscreen when you're outside will only lower your risk of skin cancer, not raise it. A new review of research on sunscreen and skin cancer risk disputes recent reports that sunscreen use may increase the risk of melanoma rather than prevent it.
Although melanoma is the least common form of skin cancer, the number of people who get melanoma is growing faster than any other type of cancer in the U.S. Approximately 54,000 new cases will be diagnosed this year.
The recent rise in melanoma cases has caused researchers to take a closer look at what factors affect a person's risk of developing the skin cancer. Most researchers believe the increase is largely the result of people spending more time in the sun, but a few recent reports have suggested that sunscreen use may increase rather than decrease the risk of melanoma.
Setting the Record Straight on Sunscreen and Melanoma Risk
In this study, published in the December 16 issue of the Annals of Internal Medicine, researchers reviewed all the studies between 1966 and 2003 on the issue of sunscreen use and melanoma risk.
Researchers found no good evidence that people who use sunscreens have a higher risk of melanomas. They say several studies did not take into account the fact that light-skinned people with several risk factors for skincancer tend to use more sunscreen that those at low risk. Despite this, the studies failed to show an association between sunscreen use and increase risk of melanoma among sun-sensitive people.
The major risk factors that may increase the risk for melanoma are:
- Family history of melanoma
- Large number of moles and freckles or unusual looking moles
- Sun sensitivity (light skin color, tendency to burn, inability to tan, etc.)
- Regular exposure to ultraviolet (UV) radiation from the sun or tanning beds
In addition, researchers say there was no proof of a dose-response effect with frequency of use or years of sunscreen use associated with melanoma risk. Many of the studies were also flawed because they relied only on people's memory of sunscreen use and sun exposure.
But many of the studies were old and did not have information about newer sunscreens with a sun protection factor (SPF) of greater than 15, the ability to block both UVB and UVA radiation, and are water-resistant. Researchers say future studies will have to address these issues.
SOURCE: Dennis, L., Annals of Internal Medicine, Dec. 16, 2003; vol 139: pp 966-978.