Why haven't we invented a sunscreen pill?

A question every pale person wants answered

sunscreen pill bottle
Necessary beach suppliesMark Nerys

Antioxidants in Polypodium leucotomos, a tropical fern, can technically block UV radiation. But antioxidants are unstable molecules, so getting them from stomach to skin is hard. Today's fern-extract pills, like Solaricare or Heliocare, reach only SPF 4, not nearly enough for daily protection, let alone a beach day. This instability issue won't be solved soon, so keep slathering up.

Want to know if your fantasy invention could become a reality? Tweet @PopSci or tell us on Facebook. Popular Science reader Chad Wells submitted this question via Facebook.

This article was originally published in the January/February 2017 issue of Popular Science, under the title "I Wish Someone Would Invent...A Sunscreen Pill."