Lizzie McGuire may have thought science class was a drag, but IRL, Hilary Duff‘s quite the DIY beauty queen. Between coffee grinds, coconut oil, and honey, the Younger actress-slash-mama has some serious at-home wellness prowess when it comes to her skin-care habits.

While the star’s got her beauty faves for beating everything from puffy eyes to airplane face bloat, she recently shared a moisturizing hack for a place that tends to be forgotten: your elbows. According to New York dermatologist Joshua Zeichner, MD, due to all the friction, the skin there gets drier than other parts of your body.

Duff’s secret? Everyone’s favorite healthy fat: avocados. “When we were little, my mom would save the avocado peels with some meat still left inside the halves when she was making guac,” she tells me. “She’d then put them on her elbows, and sometimes even her knees, as a moisturizer.”

Yes, she means you rub it on directly from the fruit itself. “It’s super simple,” Duff explains. “Cut the avo in half, and then after eating most of the avocado meat, you just kind of rub the empty shell on the dry skin.”

“Avocado meat is naturally fat-rich, which has moisturizing properties for the skin,” —Shrankhla Holecek.

Does the toast topping truly have skin benefits, though? “There’s actually something to this!” says Shrankhla Holecek, Ayurvedic expert and founder of beauty brand Uma Oils. “Avocado meat is naturally fat-rich, which has moisturizing properties for the skin. Plus, they’re packed with nutrients like vitamins such as B and K, which can have repair properties for the skin as well.”

And don’t worry, it doesn’t matter if the avocado is ripe or not. In fact, clinical researcher and beauty expert Leigh Winters, an instructor at Columbia Business School’s Venture for All program says, the less-ripe the better. “If the fruit is picked too early, it might be too watery to eat, but that may actually make it a better hydrator for your tough elbow skin.”

Just don’t expect the avocado mash to boost your overall skin health too much. “It’s moisturizing for sure,” says Winters. “But in order to see any real difference in skin tone and suppleness, you’re going to need more than the active ingredients in just one avocado,” Winters says, noting that avocado oil may be the fruit’s perfect pairing.

At the very least, the beauty hack’s bound to make your elbows look, ahem, younger (had to).

Everyone loves a good DIY—here are 3 other ingredients you can find in the produce aisle. And PSA, when cocktailing your own products, there are actually some ingredients that you shouldn’t mix into your skin care.