Sunscreen doesn't work as well as it says: What to do?

"Even a single exposure increases risk of melanoma," says Dr. Len Lichtenfeld, deputy chief medical officer at the American Cancer Society.

Back in 2012, the FDA did a major update of sunscreen standards, including banning the inaccurate, misleading terms "sunblock" and "waterproof."

[...] manufacturers can only label products "water resistant" and must state how soon they break down from swimming or sweating, either 40 or 80 minutes.

The level of protection against UVB rays is measured by something called SPF, or sun protection factor.

For UVA rays, which penetrate skin more deeply, sunscreens are rated as passing or failing government standards.

Consumer Reports' recent testing of 65 sunscreens found more than 40 percent didn't meet their SPF claims, so the magazine advises using SPF 40 or 50 to increase chances you're getting at least SPF 30.

Wear clothing that covers your arms and legs, and a broad-brimmed hat to protect your face, ears and neck.

The FDA's Michele notes that ultraviolet rays are stronger, and therefore more dangerous, at high altitudes and in southern states, so people there should be extra careful.