When you walk out into the sun on a bright day and you’re not wearing sunglasses / clip, what do you do?

You might raise a hand to block the sun from your eyes. You may lower the sun visor in your car or try to stay in the shade. But your first reaction when confronted by bright light is probably to squint.

The more you squint, the deeper the grooves in your crow’s feet will become and the older you will appear, according to the American Academy of Dermatology Association. And if you try to focus on anything with blinding light in your eyes, your eyebrows will furrow, deepening the wrinkles between your eyebrows as well.

If you wear sunglasses, you won’t need to strain to see while you’re outside on a sunny day. You can avoid squinting (and brow-furrowing in concentration), which will help delay part of the aging process.