This Fish Makes Its Own Sunscreen

As a fair-skinned person who hates the daily ritual of slathering on sticky sunscreen, I’ve often lamented the absence of a simple pill to protect my skin from UV radiation. Researchers know I'm one of many, and they have been testing various sunscreen alternatives for years. So far they haven’t found anything effective enough to replace your SPF 50. This is good news for the $1.3 billion sunscreen industry, but bad news for me and my sunburn-prone compatriots. 

Now researchers from Oregon State University may have found a solution in the lowly zebrafish. These tiny creatures produce a chemical called gadusol that absorbs dangerous UV radiation. It’s also found in other marine species like sponges and cod. Researchers originally thought they ingested the chemical through their diet, but they've discovered that zebrafish actually produce this chemical on their own. This means we might someday manufacture the stuff in large quantities for our own sun-safety use. 

Taifo Mahmud, lead author of the study, first had to figure out how the zebrafish make the gadusol. It’s a bit complicated, but the recipe calls for a particular enzyme and another protein that, when combined, biosynthesize the sun-blocking chemical. Mahmud and his team think the process is triggered by light exposure. They wanted to see if they could replicate the process in the lab, so they moved the zebrafish genes onto yeast and voila: they made gadusol.

The hope is that this process could be used to create a sunscreen pill for human use. “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," Mahmud said. 

But there are hurdles ahead. For example, getting something from the stomach to the skin isn’t easy. “If you think about taking a pill by mouth, it has to go through multiple steps,” Henry Lim, a dermatologist at the Henry Ford Hospital in Detroit, Michigan, explained to Nature. “It has to be absorbed, go through the blood and then through the liver before it gets to the skin.” 

We also don’t know how the fishy sunscreen would be absorbed into the human body or what side effects it could have, so further research is needed before gadusol can be mass produced. But the next time you break out the Coppertone, take heart in knowing that protecting your skin by popping a pill may not be that far away.