What Is Serum and How to Apply It According to Derms in 2022

Trust me: You definitely aren’t alone if you get a little overwhelmed when you hear the word “serum.” Like, wtf even is a serum—and how (slash why) should you add one to your skincare routine? Well, turns out serums are a lot less complicated than you might think: They’re basically super-concentrated liquids that blast your skin with active ingredients (whether that’s brightening niacinamide, hydrating hyaluronic acid, or zit-fighting salicylic acid) to treat everything from dry, sensitive skin to fine lines and wrinkles. And since there are, like, thousands of serums on the market, they’re super customizable (think: you can get super specific about your preferences and needs).

So to get the full low-down on serums—including their long list of benefits, how exactly to apply them, and the best ingredients to look out for—I called up dermatologists Joshua Zeichner, MD, and Michelle Henry, MD, to find out everything there is to know. Keep reading for the ultimate guide, plus a few product recs you’ll definitely want to add to cart.

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What exactly is a serum?

Serums are lightweight skincare products designed with one goal in mind: delivering a high concentration of active ingredients to your face. The best part about serums? They’re super customizable to your skin type and concerns. That means you’ll want to choose one that addresses your skin’s particular needs, says Dr. Zeichner, since not all serums are created equally. Think: Your best friend’s favorite serum might work great for her fine lines, but you’ll probs need something different for your dark spots.

So, what exactly makes a serum different from other products in your lineup? Dr. Henry credits the high concentration of actives.“Serums are made to deliver hyper-concentrated levels of active ingredients, and therefore are better for getting more immediate results and addressing specific concerns,” she says. “Serums are far more concentrated than creams, which is why they are also more expensive.”

What are the benefits of face serum?

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One more time for the ppl in the back: Serums are completely customizable to your routine and specific needs, which means the benefits are vast. They can hydrate, soothe, protect, exfoliate, plump, you name it—it all just depends on your serum’s active ingredients (more on that in a bit, though popular ingredients include hyaluronic acid, niacinamide, glycolic acid, and more.). There’s just one thing to keep in mind: Even though serums are an excellent addition to most skincare routines, they shouldn’t replace any of your products—you’ll definitely want to pair with your usual cleanser and moisturizer (and if you’re applying in the morning, SPF).

What’s the difference between serum and essence?

Great question. Essences—like serums—are also made with active ingredients, but they’re typically more watery and a tad less concentrated. That means essences are less likely to cause irritation if you have ultra-sensitive skin, says Dr. Henry. BTW: Hydration is usually the name of the game when it comes to essences, so if you’re extra dry (or, again, sensitive or prone to irritation), you might want to consider adding one to your routine (like the or the ).

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How do you apply face serum?

If you’re looking to add a serum to your skincare routine, knowing how (and when!) to apply it is key. Serum is typically applied as the second or third step in your skincare routine—directly after your cleanser and (if you use it) toner. Dr. Zeichner recommends smoothing a pea-sized amount over your clean, dry skin. You’re then going to want to wait 30 to 60 seconds to layer on your remaining products (think: spot treatments, moisturizer, face oil, and sunscreen).

P.S. If you’re still a bit confused about the whole skincare order thing, Dr. Henry recommends applying your products from the thinnest to thickest consistency.

What’s the best serum?

Since there’s no “one size fits all” when it comes to serums, you’ll first want to figure out your skin’s specific needs. If you’re acne-prone, go for serums spiked with ingredients like salicylic acid, benzoyl peroxide, or sulfur to treat and prevent existing breakouts. Dry skin bugging you? A ceramide, hyaluronic acid, or vitamin E serum could be right up your alley. If you aren’t quite sure where to start, try booking an appointment with a dermatologist who can better gauge exactly what’s going on with your skin and how to find the best serum for your routine.

And while serums can definitely address more than one issue, they’re generally categorized as antioxidant, acne, hydrating, brightening, or anti-aging. Here’s what you can expect from each:

1. Antioxidant serums

    Antioxidant serums are great for overall skin protection and serve as a nice addition to just about anyone’s skincare lineup. They help protect against environmental and UV damage and are also great anti-agers, thanks to ingredients like vitamins C and E, resveratrol, niacinamide, and more. If you’re applying an antioxidant serum during the daytime, make sure you follow with a minimum of SPF 30.

      2. Acne serums

      Acne serums are, you guessed it, the ones that treat and prevent breakouts (and/or the dark marks and spots they leave behind). Hero ingredients typically include chemical exfoliants like salicylic acid (it’s great for getting rid of blackheads, whiteheads, and excess oil) and glycolic acid (it’s excellent for fading hyperpigmentation and minimizing the appearance of pores) or medications like benzoyl peroxide (it’s a tried-and-true acne fighter for blackheads, whiteheads, pustules, and cysts).

      These serums can definitely be on the harsh side, so it’s never a bad idea to chat with your dermatologist before adding one to your routine.

        3. Hydrating serums

        The primary goal of a hydrating serum is to give your skin an extra shot of moisture. They typically contain ingredients like hyaluronic acid, which acts like a sponge to grab onto water and pull it into your skin. Dr. Zeichner says you should always apply face cream over your hydrating serums (especially hyaluronic acid ones) to help lock in the moisture. These bbs can be especially great for dry or sensitive skin types.

          4. Brightening serums

          Look for a brightening serum if you’re trying to lighten dark spots and even out your skin tone. Vitamin C is usually the go-to here, which Dr. Zeichner says helps block the production of abnormal pigmentation to brighten up dark marks. Niacinamide, tranexamic acid, and kojic acid are also great choices, all of which help address hyperpigmentation and minimize discoloration.

          5. Anti-Aging serums

            Trying to minimize your fine lines and wrinkles? Anti-aging serums are your best bet, which usually call on ingredients like retinol (it speeds up collagen production so your skin looks plumper and firmer), glycolic acid, and peptides, says Dr. Henry. One thing to keep in mind: Even though retinol is an excellent anti-ager, it takes a minimum of three months to see a visible reduction in your fine lines. It’s also pretty drying during the first few weeks, so it’s best to start low and slow when adding a retinol serum to your routine.

            The final word

            If you’re looking for an easy way to level up your skincare routine, you can’t go wrong with a serum. They’re kinda the perfect solution for treating your most pressing skin issues (whether that’s dryness, acne, fine lines, dark spots, etc.), and they’re v easy to apply (remember: always slather on your serums to clean skin—post-cleanser, pre-moisturizer). Who knows, a face serum might just be your answer to getting soft, dewy-as-hell skin.

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            Valeriya Chupinina

            Valeriya Chupinina is a freelance beauty and wellness writer exploring the multifaceted connection between the aesthetic and internal. You can find her work in outlets like Coveteur, HYPEBAE, and NBGA. In addition to her editorial work, she consults on social media strategies for brands. You can keep up with her on Instagram @valeriyaliyevna.