I remember when hyaluronic acid was catapulted into the skin care stratosphere. It was almost as if overnight, the humectant became A-List status (well, in beauty circles at least), rivaling the likes of retinol and vitamin C. We went from editors having to teach people how to pronounce it—hi-ah-lew-ron-ic—to everyday folks rattling it off as part of their daily skin care staples. A star is born, indeed.For insiders, the rise to fame was peculiar. Hyaluronic acid had been part of cosmetic chemists’ classic arsenal well before it gained name recognition. Not to mention, the body makes its own supply of hyaluronic acid. So it certainly has never been “new.” Regardless, hyaluronic acid proved to have massive staying power—especially in serum form. Hyaluronic acid serums are a wonderful product for almost any skin type and concern—but it’s particularly helpful for those with dry or maturing skin. If you’d like to add it to your own routine, check out our favorites below. All tested and vetted by the mindbodygreen beauty team. It’s a thinner, more gel-like texture than other HA serums. I love that it spreads over skin effortlessly, and provides an immediate refreshing effect. Thanks to the quick absorption time, I found it to fit easily into my skin care routine, and it played well with my other products.However, Schneider notes she found it to be a bit more slimy than other HA serums she’s tried. “It’s a bit slimier than other options, which is my only hesitation. I personally don’t mind a bit of stickiness if it means I’m getting drenched in hydration, but worth noting for folks who prioritize consistency.”In addition, she notes she doesn’t mix it with oil-based products, so be sure to allow for dry down time: “I also found it to pill under oil-based products like SPF and makeup. But if you follow up with a water-based moisturizer and let the combo fully dry down, you should be A-OK.”It almost feels more like a light lotion than a gel (it still is, however, very much a serum—so use it during your treatment step). A little goes a long way, and be sure to spread it out in one thin layer, so it sinks in easier. There is not a trace of residue or tackiness after application. It goes on like silk.Schneider agrees: “It’s still thin enough to remain serum-like, but it’s opaque and spreadable unlike most formulas I’ve tried,” she told me. “There is zero stickiness, tackiness, or pilling with this formula. It practically melts into the skin—for me, it has the best texture by far.”It also works well with other products, she says: “Not sticky or tacky at all, and it wears exceptionally well under makeup! It’s so hydrating, in fact, that I bet you could even use it in place of moisturizer on warmer days.”This is capital-H Hydration. Skin looks noticeably dewier instantly after applying. It creates a smooth, soft canvas for the rest of the routine to follow. However, the real magic is in the long-term results.Ourself is known for their biotech delivery system (called Subtopical Firming Technology) that drives the ingredients deep into the skin to exactly the layer they need to go. This, naturally, improves the ingredient’s efficacy. And in the case of their HA serum, it means that the HA molecules can provide sustained hydration. When I use this product, my skin stays moisturized no matter what. As Schneider told me, “This serum certainly fills out fine Iines, but I noticed other formulas perform more immediately in terms of plumping. Over time, though, I definitely saw smoother results.”There is no regulated definition of “clean” or “natural” in the beauty industry. So it’s really up to brands, publications, and individuals to create their own definition.Natural ingredients are plant- or mineral-derived and are extracted from natural-world sources. We prioritize natural ingredients when they make sense in the formula, as many botanicals are hugely beneficial for the skin. (A few below!)But we also understand that lab-derived ingredients can sometimes be the better alternative, as they can be more environmentally friendly and less irritating for the skin. We also believe that “natural” formulas are a spectrum, as it’s very rare that a product is 100% natural—so a natural formula may still contain ingredients that are synthetic. Clean formulas can include both natural and lab-derived ingredients. Clean ingredients are those that are identified as safe for the skin and overall health as backed by research. Clean formulas tend to be more gentle for skin, as they avoid sensitizing ingredients. We believe that what ingredients are deemed “safe” is an ongoing conversation.