It’s The First Day Of Summer, How Much Sunblock Do You Need?

How Much Sunblock Do You Need?
YEW Staff
Written by YEW Staff

Since you were a grom, someone’s been yelling at you to put on your sunblock, but how much sunblock do you need? Will a lil dab do you, or is it better to lather yourself up in an armor of white lotion? Well, summer’s here and it’s time to get these questions answered.

First, What is SPF?

SPF, or Sun Protection Factor (“ohhhh, that’s what it means,”) refers to how well sunblock protects you from harmful UVB rays. Simply, the higher the SPF number, the more protection you get from sunburn / skin cancer.

UVA rays on the other-hand, prematurely age your skin, causing wrinkles, sun spots, and leather face. “Broad Spectrum,” or “Full Spectrum,” sunscreens offer protection from UVAs where regular SPF sun blocks do not.

Are higher SPF sunscreens better?

Yes, a sunscreen with a 30 SPF will block out 97% of harmful UVB rays, where a sunscreen with a 50 SPF (or higher) will block 98 percent. Per the American Academy of Dermatology, there isn’t a sunscreen on the market that blocks everything out.

Sunscreen application: how much and how often?

One ounce, or enough to fill a shot glass, every two hours (or more if you’re swimming or sweating.) Avoid uneven application.

The Shadow Test

A super easy way to tell how much UV exposure you are getting is via your shadow:

  • If your shadow is taller than you, UV exposure is likely to be lower.
  • If your shadow is shorter than you, UV exposure is likely to be higher (requiring sunblock.)
how much SPF do you need

Infographic Credit: Department of Dermatology at Keck Medicine of USC

About the author

YEW Staff

YEW Staff