Sunscreen Prevents Cancer continued...
Importantly, however, the study participants in that trial carefully and repeatedly applied sunscreen while also seeking shade and wearing protective clothing.
“The best data that’s out there shows the combination of seeking shade, wearing protective clothing and wearing sunscreen, those three things together clearly lower your risk,” says Darrell S. Rigel, MD, a clinical professor of dermatology at New York University.
Rigel says there is an important caveat about this study which should reassure people about their sunscreen.
The latest data used in the study is now about five years old, and he says sunscreens have improved in a couple of key ways since then.
“How long it lasts, 'substantivity' it’s called, has markedly improved, really with new formulations,” he says, and many of the newer formulations offer better broad-spectrum protections against both UVB, the burning rays, and UVA, the cancer-causing rays.
New FDA rules for sunscreens, which will go into effect next year, should make it easier to pick a good product.
That’s important, Rigel points out, because it’s not always possible to stay in the shade or wear longs sleeves.
In those cases, it’s more important than ever to put sunscreen on correctly.
Experts say the rule of thumb is a golf ball-sized blob for every exposed body part, applied at least 30 minutes before going outside, since sunscreen takes that long to absorb into the skin.
That much sunscreen should be reapplied every two hours, and even more frequently, every 60 to 90 minutes, when swimming, sweating, or using a spray product, since those don’t last as long.