Summer 2015 Health Tips: What You Need to Know About Sunscreens, SPF & Your Skin

Most Americans know that wearing sunscreen can help protect the skin against the sun's harmful UV rays as well as prevent premature aging and skin cancer. However, a new study shows that many consumers are confused about their sunscreen and the terminologies printed on its bottles.

According to the American Academy of Dermatology, sunscreen labels can help indicate the product's effectiveness at preventing or protecting different kinds of skin conditions brought about by the exposure to the sun.

A sunscreen labeled with "broad spectrum" means that it can protect the skin against two types of harmful UV rays, which are UVA rays and UVB rays. It can also protect against skin cancer, sunburn and premature skin aging as well.

UVA contributes to skin aging and wrinkling and is responsible for tanning the skin. UVB causes sun burn and skin reddening and plays a major part in the development of skin cancer, according to the Skin Cancer Foundation.

Sun protection factor or SPF is indicative of how long it will take for the skin to get sunburned with the application of the sunscreen. It is recommended to select a sunscreen with an SPF rating of at least 30. Experts, however, warn against using sunscreens with SPF higher than 50. They recommend to lather sunscreen generously for maximum protection and to reapply it as necessary.

Sunscreen labeled with "water resistant" indicates that the product will stay on the skin even if it gets wet. Most water resistant labels are followed with "40 minutes" or "80 minutes" and this indicates how long you need to reapply the product again.

A new study published in the journal JAMA Dermatology by scientists from Chicago's Northwestern University Feinberg School of Medicine shows that many people are confused about sunscreen terminologies.

For the research, the scientists interviewed 114 patients who had visited the Northwestern Medicine dermatology clinic in the summer of 2014. They were quizzed regarding sunscreen terminologies and labeling.

Only about 80 percent of the participants bought sunscreen in the last year to protect themselves against sunburn and skin cancer.

"A lot of people seem unsure about the definition of SPF, too," said lead author Dr Roopal Kundu of Northwestern University, as perScience World Report. "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."

According to the New York Daily News, less than 40 percent of the patients understood how sunscreen works.

"They think that SPF means everything," Dr Kundu said. "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."

Dr Kundu adds that there needs to be a new kind of labeling system that involves stars to indicate UVA protection and the SPF index for UVB protection.