If skin cancer prevention education had to be boiled down to two words, it would be these: Wear sunscreen.
"Sunscreens may not be the end-all, but it's the best we have," said Dr. Michael Gold, a Nashville-based dermatologist.
But slapping on a few drops of 15-SPF down by the pool is no an empty gesture, dermatologists say, but not nearly as effective as needed.
Start early
"You get 80 percent of your sun damage before you hit 18 to 20," said Dr. Gold.
Damage caused in younger years may not show up until later into adulthood. It can take 20 to 30 years to develop skin cancer after a burn, making the importance of emphasizing proper sunscreen use to children.
"Getting burned as an adult is the lesser of two evils," Murfreesboro dermatologist Dr. Michael Bell said, noting that sunscreen use in later years of life is really more about preventing acute discomfort than about preventing skin cancers. Cancerous spots that arise in persons aged 50 and above are likely the result of damage acquired in the 20's and 30's.
Understand SPF
Sun Protection Factor, is a measure of how much UV radiation is needed to burn skin that has been protected by sunscreen, according to the Food and Drug Administration.
"SPF is a curve scale measurement of how fast it takes you to burn," said Dr. Gold. He described the curve in an S-shape. "When you get toward the top of the S, you're hitting about 30. In the middle, you're about 15."
"We always say (use) 30 and above," said Dr. Gold, speaking on behalf of his colleagues in dermatology. And while he said there's not a strong difference between 30 and 50, "there's a big difference, however, between SPF 15 and SPF 30."
SPF only measures UVB protection. UVB are the burning rays, the ones that cause the more acute effect. UVA rays are associated with long-term effects like photodamage, wrinkles and skin cancers.
"That's sort of been neglected in all this," said Dr. Gold. "(Dermatologists) have known this for years, but passing it on to people has not been easy). (A sunscreen labeled) broad spectrum means it has some UVA protection but nobody knows what it is."
A proposed FDA regulation would change the label on sunscreen bottles to include both SPF (UVB protection) numbers and a four star rating system measuring UVA protection.
Use it Right
In the NewsU.S. Sen. Charles E. Schumer (D-NY) has been pressing the FDA to reveal findings on links between skin cancer and retinyl palmitate, a Vitamin A derivative found in most sunscreens.Dr. Gold said he thinks anxieties about retinyl palmitate are premature and mostly unfounded."There's no question if you put an IV in somebody and started giving them retinyl palmitate, eventually they're going to develop a cancer. Vitamin A in toxic doses makes people sick," he said."I can't imagine there would be any concerns (with typical use)." The compound, he said, is very similar to that of Retin-A, which dermatologists use as an anti-skin cancer product.
The efficacy of an SPF is decreased if sunscreen is not applied properly. According to Dr. Gary Claudel, incidence of skin cancer would decrease "if everyone put on a 15 the right way."
The keys to proper sunscreen use are amount, preparation and reapplication.
"The problem is (most people) don't put on the amount that's recommended," said Dr. Claudel, emphasizing the recommended amount of one ounce (about a shot glass full) for all exposed skin.
Reapplication is essential every two to three hours of outdoor exposure, even if the bottle says waterproof.
"Most sunscreens aren't waterproof," said Dr. Gold, "so you have to reapply especially after the water."
The other key is to apply sunscreen 30 minutes before leaving the house.
"The ultraviolet starts to hit you as soon as you walk out the door," said Dr. Claudel.
Dr. Gold said he cringes when he sees his golf buddies spraying on their sunscreen on the first tee. "It's not going to do much for the first 30 minutes to an hour," he said. "The people who I play golf with know they better have their sunscreen on."