Sunscreen has long been touted as a protective measure against melanoma and sunburns, but some recent evidence has suggested otherwise. Sunscreens do a good job of blocking ultraviolet (UV)B rays, which are known to cause melanoma, but many do not block UVA rays. Although UVA radiation was long thought to produce only tans, it has recently been linked to melanoma.
Dr Crane said she recommends the newer broad-spectrum sunscreens that block both UVA and UVB radiation, at the highest SPF available.
UVA exposure is more or less constant throughout the day. So although the sunburn danger wanes when the sun is low in the sky, risk for UVA exposure can remain.
This is "an excellent study, very well done, and longitudinal, which is good," said Susan Nohelty, PhD, professor of public health and epidemiology at Capella University in Interlaken, New York, who presented a separate study during the session.
"I have lighter skin, so I do use sunscreen, but you have to wonder if sunscreen does help," Dr Nohelty added.
She also said she wonders if the broad-spectrum sunscreens will prove to be more beneficial. "I think it would be fascinating to evaluate the different kinds of sunscreen," she said.
In addition to recommending such broad-spectrum sunscreens, Dr Crane champions hats and protective clothing. "Kids on the beach should be wearing those swim shirts; they shouldn't be running around with just trunks or a bikini," she said. Broad-spectrum sunscreen can then be used on areas that can't be covered.