So we all know hyaluronic acid to be the MVP of skincare—or, at least, that's what you've read/heard/seen in every single story, commercial, and product for the last year. (We get it, hyaluronic acid—YOU'RE POPULAR.) And although, yes, this little ingredient is usually the key to plump, glowing skin, it still needs to be used correctly, or it can make your face sincerely unhappy.
So if you have officially reached peak levels of confusion about WTF hyaluronic acid even is and how to use it, please allow dermatologist Lily Talakoub, MD, to explain everything you need to know about hyaluronic acid benefits and the correct way to use it in your skincare routine.
What is hyaluronic acid?
Hyaluronic acid (HA) is a type of molecule naturally found in your skin that pulls water from the air and sucks it into your face like a sponge, helping your skin stay moist throughout the day. Because of its ability to retain water, you'll also find it in a lot of hydrating skincare products, like face serums, moisturizers, and makeup products, like foundations and concealers. It's also the go-to ingredient used in fillers (see: lip injections), since, according to Dr. Talakoub, it works similarly when injected as it does topically, binding to water in your body and making the skin plump up.
Which hyaluronic acid product is best?
Gels, gel moisturizers, moisturizers, serums—you can find hyaluronic acid in all kinds of skincare products. In short, Dr. Talakoub recommends using a gel-based product for oily skin, or an oil-based product for dry skin. But if you're using a straight-up serum, you absolutely need to layer it under a moisturizer and/or face oil (more on that below).
What is another name for hyaluronic acid?
If you've scanned the ingredients list on your favorite hyaluronic acid product and don't see anything that says "hyaluronic acid" on there, don't freak out. Different products include different forms of the ingredient, one of the most common being sodium hyaluronate (a salt form of hyaluronic acid). So when it comes to sodium hyaluronate vs. hyaluronic acid, is one better than the other? Although they are different, Dr. Talakoub says the many synthetic hyaluronic acid molecules on the market essentially do the same thing: Retain moisture in the skin.
Can I use hyaluronic acid every day?
Yup! And you can even use it twice a day as long as you're applying it to clean, damp skin, then locking it in with a moisturizer and face oil. "If you put hyaluronic acid on top of sunscreen or a moisturizer, it’s not going to work," Dr. Talakoub says. "It’s got to sit on that top layer of your skin to hold the moisture in so it doesn’t evaporate from your skin barrier."
It might seem obvious, but it's actually one of the biggest mistakes people with dry skin make with hyaluronic acid: Thinking the only thing they need to use is a serum. Instead, think of hyaluronic acid as a team player that works best when used with a cream. Dr. Talakoub says even though hyaluronic acid holds water in the skin, a normal moisturizer that’s made for people with very dry skin has an emollient to lubricate the skin and an occlusive to hold the oils in the skin.
Is hyaluronic acid bad for your skin?
On the contrary! Hyaluronic acid is great for your skin—when used and applied correctly and in the right order. Here's the deal: If your dry skin is sitting in a humid room, and you slather on hyaluronic acid, it'll pull moisture from the air and into your dry face. But—but!—if your moisturized skin is sitting in a dry room, the hyaluronic acid sitting on top of your face will pull water out of your skin and evaporate it into the air, leaving your face drier than before.
How do you prevent this? By applying your hyaluronic acid to slightly damp skin, then immediately slathering on a rich moisturizer to lock it all in. And, ideally, topping it off with a layer of face oil before bed to maximize the hydration.
What are the side effects of hyaluronic acid?
According to Dr. Talakoub, hyaluronic acid is something that everybody's skin could use, and it very rarely has any side effects (our bodies naturally make it, remember?). With that said, there are different sizes of hyaluronic acid molecules found in products that penetrate your skin at different depths. Studies show that hyaluronic acid with lower molecular weights penetrates deeper into the skin, which can cause inflammation, so if you're noticing any dryness or irritation from your HA serum, stop using it and switch to another, or ask your dermatologist for options.
Overall, hyaluronic acid is great for sitting on top of your skin and preventing the moisture from being lost to the outside environment—but it's not foolproof, so use it wisely. Always apply it to clean, damp skin, lock it in, and consult your derm if you're noticing anything unusual. But all in all, it's a pretty harmless and helpful ingredient.
This article originally appeared on Cosmopolitan.com. Minor edits have been made by the Cosmo.ph editors.