Wednesday, April 23, 2014
On a recent holiday, my girlfriend got sunburn on two separate occassions. The first time she was wearing sunscreen. The second time she was under a sun umbrella, but had no sunscreen on. Despite the first burn appearing to be worse (more red), she is worried the second burn (not as red) may have done more significant damage because of the lack of sunscreen. Is she right to be more worried about the second case?
Regardless of how the sunburn occurs, that is with sunscreen or without, it is a sunburn. That means there is the same effect or damage on the skin if the sunscreen wore off, enough wasn't applied, or none was applied at all. The appearance of the sunburn indicates damage, so she shouldn't be worrying about the second one. Instead, she should be a little worried because she had two sunburns, especially so close together. While an umbrella provides shade, unless the umbrella material is specifically designed to be a UV block, sitting under an umbrella provides very little protection against sunlight. The sun's rays not only can penetrate through the material of the umbrella, but also bounce off the sand and onto your skin. That is why you need to wear a sunscreen that protects against UVA and UVB rays, remember to apply enough of it (a shot glass full) at least 15 min before going out in the sun, and to reapply especially after swimming or sweating regardless if it says it's waterproof.
Tatiana M Oberyszyn, PhD
Associate Professor of Pathology
Associate Professor of Molecular Virology, Immunology & Medical Genetics
College of Medicine
The Ohio State University