Fish and other forms of ocean life that live on upper reefs are exposed to unrelenting sunlight.

So why don't they get sunburned like humans?

The answer is that they produce a protective chemical, a natural sunscreen, which could translate into better sunscreen formulas for humans, researchers have discovered.

This chemical, known as gadusol, protects against UV radiation, which cause sunburn and can lead to skin cancer.

Previously it was believed that fish acquired the chemical through their diet or through a symbiotic relationship with bacteria. But, by doing experiments with yeast, Oregon State University researchers were able to prove that zebrafish produce it internally.

Gadusol is found in other forms of sea life and there is evidence that reptiles and birds also produce it. But humans lack the genetic ability to do so, the researchers said.

They believe their findings could open the door to large-scale production of the gadusol for use in sunscreen and also as an antioxidant for pharmaceutical uses.

"The fact that the compound is produced by fish, as well as by other animals including birds, makes it a safe prospect to ingest in pill form," says Professor Taifo Mahmud, lead author of the study.