Well, don’t knock it till you try it—or check out this TikTok user who already did. In the viral video (it currently has one million views and counting), she repurposes a cult-favorite serum and rakes it through the lengths of her hair. “After only two days, I saw and felt a major difference,” she explains. And after a full, two-week experiment, her hair “feels so soft and is way more manageable.” What’s this secret ingredient, you wonder? Oh, it’s hyaluronic acid. In fact, plenty of leave-ins, shampoos, and stylers include the ingredient in their formulas already—hyaluronic acid for hair is not a new concept. But from this TikTok experiment, it seems using a proper skin care serum can be just as effective, if you can spare a few drops. “HA lives in my shower for the face and hair,” says board-certified internal medicine physician and skin care expert Zion Ko Lamm, M.D., in a duet video. If you have dry, frizzy, brittle, or damaged locks, she considers it a worthy addition to your routine (she typically uses it as a pre-shampoo or leave-in treatment). Best part? Like Lamm, you can streamline your routine and keep one vial on hand for your skin and hair—both will drink the HA right up. The only caveat to note is that hyaluronic acid doesn’t exactly seal moisture into the strand. It helps draw in moisture from the environment, yes, but as Lamm says: “It does not take the place of hair oils.” You’ll still want to lock in all that water with an occlusive product, or the precious hydration can seep out, and your hair may become even more limp and dry than before. As we mentioned above, don’t forget to follow up with a hair oil, then feel free to style as usual. (And if you’re partial to an air-dry, check out our handy guide.) Repeat every wash day, if you please, and notice how your hair changes: As the HA plumps the strand with moisture, your hair should appear oh-so-soft and shiny.
