If the fountain of youth were an actual thing, we're willing to bet that it would be filled to the brim with SPF. While there’s no questioning the importance of sunscreen in your anti-aging regimen, not to mention overall skin health, does the same hold true for your hair?

By Jenny Jin
ONOKY - Fabrice LEROUGE/Getty Images

Scientifically speaking, “SPF is not really necessary for the hair shaft because unlike our skin, hair is not comprised of living cells,” says Julia Tzu, medical director and founder of Wall Street Dermatology. That said, you definitely want to keep your scalp protected. “For the best protection, I recommend wearing a hat,” says Heidi Waldorf, director of laser and cosmetics dermatology at the Mount Sinai Center in New York. Another option is to apply your regular sunscreen down your part, and on the tops and sides of your ears. You can also try using stick versions, like Neutrogena Ultra Sheer Face + Body Stick ($8.80, drugstore.com), which are easy to use and reapply.

Cosmetically speaking, “ultraviolet radiation will affect your hair in ways you might want and ways you don’t,” says Waldorf. On natural hair, it can have a lightening effect (think back to those sun-kissed highlights you’d get as a kid). On color-treated hair, it may have more of a fading effect. And regardless of whether your strands are processed or not, “too much sunlight will dry out hair and make it brittle,” warns Edward Tricomi, Master Stylist at Warren-Tricomi Salons.

Luckily, many styling products include UV filters that protect strands while also tamping down frizz and adding shine. Look for ones with moisturizing ingredients like argan, coconut, or sunflower seed oils. Two to try: Fekkai Pré-Soleil Hair Mist ($20, fekkai.com) and Phyto Phytoplage ($30, sephora.com).