There's no such thing as waterproof or sweatproof. It's technically impossible for a sunscreen to be waterproof or sweatproof, says the FDA. Instead, sunscreens can be water-resistant, but only if they retain their original SPF (Sun Protection Factor) after 40 minutes in water.
Credit: Ian McDonnell / Getty Images
Powered By ZergNet
Why the 63-Year-Old American Rock Icon Still Won't Back Down
Plus: Wildfire Epidemic: Climate Change and the Burning of the West
ON NEWSSTANDS NOW
Richard Linklater's Life Advice
Tom Petty Still Won't Back Down
Sign up to receive the Men’s Journal newsletter and special offers from MJ and its marketing partners.