Turns out, a few oral sunscreens already exist, based on the theory that antioxidants offer sun protection. Laboratory studies provide some evidence in support of this idea. When scientists feed vitamin E to hairless mice, the animals show less skin damage upon exposure to ultraviolet light. Dermatologist Salvador González Rodríguez has studied an extract made from a fern called Polypodium leucotomos. The substance, which is high in antioxidants, may decrease sun-related DNA damage in humans, he says. But as a consultant for a Spanish company that makes an oral sunscreen, Rodríguez has skin in the game, so to speak. And he admits that oral sunscreens don’t work that well when measured in the standard ways: “If we evaluate protection in terms of how conventional sunscreens are evaluated, then antioxidant-based oral sunscreens provide very low SPF.”
That doesn’t mean we’ll be stuck slathering our bodies with goopy lotion as we lurch into a globally warmed future. Many marine creatures that live in shallow water produce chemicals called mycosporine-like amino acids, which function as a natural sunscreen by absorbing UV light. These compounds have been found in bacteria, algae, and fungi. Some scientists think it may be possible to pass the compounds on to humans too, though so far, no one has had much success.
This article originally appeared in the August 2014 issue of Popular Science.