Consumers are relying too much on Sunscreen Factor Protection (SPF) values and are confused by sunscreen terminology, says a new study conducted by Northwestern Medicine and published in the journal JAMA Dermatology. The study reveals that only 43 percent of people surveyed understand the definition of SPF and only seven percent know what to look for on a label if they want a sunscreen that offers protection against early skin aging.
Sunscreens with SPF help protect the skin from ultraviolet UV-B rays which are the main cause of sunburns. Research has also shown that UV-A and UV-B can contribute to premature skin aging and skin cancers.
In 2001 the Food and Drug Administration announced new regulations for sunscreen labels to emphasize the importance of broad-spectrum protection sunscreen that protects the skin from UV-A and UV-B rays.
The Sunscreen Survey
One-hundred and fourteen people who attended the Northwestern Medicine dermatology clinic during the summer of 2014 were surveyed to find out how well they understand new sunscreen labels as well as evaluate how much they know about sun protection.
- About 80 percent of those surveyed had purchased sunscreen in 2013, and 75 percent said preventing sunburn was a top reason they wore sunscreen, followed by preventing skin cancer - almost 66 percent.
- The three top factors influencing their decisions to purchase a particular sunscreen were highest SPF value, sensitive skin formulation and water and sweat resistance.
- Almost half reported buying sunscreen with the highest SPF value available.
The participants were also shown an image of the front and back of a common sunscreen with an SPF of 30 to find out what they knew about the label.
- Many had trouble identifying sunscreen terminology on the label.
- Only 38 percent correctly identified terminology associated with skin cancer protection.
- About 23 percent were able to correctly identify how well the sunscreen protected against sunburn.
- Only seven percent were able to correctly identify how well the sunscreen protected against early skin aging.
They were also shown another sunscreen label where UV-A protection was designated with a star rating and UV-B protection was designated as an SPF value. Nearly 80 percent were able to determine the level of UV-A protection and close to 90 percent could determine UV-B protection.
"We need to do a better job of educating people about sun protection and make it easier for them to understand labels," says Dr. Roopal Kundu, lead author of the study, associate professor in dermatology at Northwestern University Feinberg School of Medicine, and a dermatologist at Northwestern Memorial Hospital. "We recommend you buy a sunscreen lotion labeled 'broad spectrum protection' - which helps to protect against both types of UV rays with an SPF of 30 or higher that is also water resistant. SPF 30 blocks 97 percent of the UVB radiation, but, you need to reapply it every two hours, using about a shot glass full of lotion over your exposed skin, for the best results. Just because you buy SPF 100 doesn't mean you are 100 percent protected. Staying out of the sun is the only way to guarantee 100 percent protection. A lot of people seem unsure about the definition of SPF, too. Only 43 percent understood that if you apply SPF 30 sunscreen to skin 15 minutes before going outdoors, you can stay outside 30 times longer without getting a sunburn."