When summer rolls around, we’re all reminded to “wear sunscreen!” We’ve all heard about how it’s important to wear sunscreen with a high SPF—but do you really know what SPF means, or why it’s so important? As dermatologists, we see a lot of confusion around SPF and how it protects your skin. So, let’s take a few minutes to break it down.
What Does SPF Actually Mean?
SPF stands for Sun Protection Factor. It’s a measure of how well a particular sunscreen protects your skin from UVB rays, which are the main cause of sunburn and a significant contributor to skin cancer.
If your skin would normally start to burn after 10 minutes in the sun, applying a sunscreen with SPF 30 should theoretically allow you to stay in the sun as much as 30 times longer—up to 300 minutes—without burning. It’s important to note that this is under ideal conditions, with proper application and no sweating, swimming, or wiping it off. That’s why it’s important to choose a sunscreen with a high SPF and to