SPF — Higher really is better
A recent study on SPF published in the Journal of the American Academy of Dermatology (JAAD, 2018; 78: 902-910) demonstrates that higher sun protection factor sunscreens really do provide additional benefit. This study evaluated skiers in a double-blind, split-face, randomized study. In this study, skiers in Vail, Colorado wore SPF 50 on one side of the face and SPF 100 on the other side of the face. They were allowed to do their normal activities and were then evaluated the next day to see if there was any evidence of sunburn erythema. The SPF 100 sunscreen side was found to be significantly more effective in protecting against sunburn.
The study supports our belief that if you are going to be out in a lot of sun, the higher the sun protection factor, the better! Another factor that may be important is that many of us apply far less sunscreen than we should, so you might think you are getting an SPF 50. However, you might be applying such a thin layer that you are only getting the equivalent of SPF 20! Consequently, make certain you apply enough sunscreen to provide adequate protection and if you decide to go to a higher sun protection factor,