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Apparently, 87% of women are confused by skincare.

And the word “serum” is confounding enough to make even the most confident, put-together, grown woman break out into a light rash in the Sephora aisle.

So are serums legit? Or are they’re just another “essential” product we’re all coerced into thinking we need in order to be youthful? And if they’re legit, which of the 87,346 serums should I buy?

Welp, here we go.


Simply put, serums are highly concentrated treatments that powerfully target different skin concerns, containing a mix of potent, active ingredients. Our favorite Aesthetician-in-Chief, Candace Marino, calls them "power products." They generally come in “a liquid to gel-like texture,” and consist of “high concentrations of active ingredients in smaller molecules that are able to penetrate the skin and go to work at a deeper level where they can create change.”

They come in all sorts of formulas and categories, and here are just a few different types:

  • Hydrating
  • Exfoliating
  • Anti-Acne
  • Brightening
  • Anti-Aging 


Like anything else, some serums are more effective than others, but generally, serums are not total bullshit. There have been tons of clinical trials demonstrating their efficacy for everything from fine lines to hydration and sun damage. And dermatologists, like Dr. Abigail Waldman, instructor of dermatology at Harvard Medical School, highly recommend them as effective treatments, especially to address anti-aging concerns.

And while you don’t have to spend hundreds of dollars to find a serum that works, you need to find serums that use quality ingredients. Candace believes that “medical grade serums are your best skincare investment because these companies spend their dollars on quality ingredients, research, formulation and clinical trials, while mass-produced brands spend their money on marketing and have less quality control.”

The quality of ingredients matters, so if you’re new to serums and not sure what to spend your money on, we recommend this:

  • Start with brands that validate their ingredients and products with clinical studies, like iS Clinical, PCA Skin, and SkinCeuticals.
  • Take full advantage of sampling—ask sales associates at Sephora, the department store, or your local beauty store if you can take home a sample of a few different serums, that way you can test them before you commit to buying. But don’t expect magic after two nights. Try to be sure you don’t have a bad reaction, and that the product agrees with your skin.
  • Ask your aesthetician/dermatologist for recommendations. They usually know the best, science-backed skincare on the market, and they’ll know what works well for your price point.



Targeted skincare treatments that will clear my pores and shrink my wrinkles and hydrate and soothe and brighten? Done. Yet, knowing how and when to apply a serum can feel perplexing, especially when most of us can barely remember to remove makeup or put on sunscreen.

But, it’s actually pretty simple; serums go after cleansing and toning/spritzing, and before moisturizer, SPF, and/or a hydrating oil. An easy, serum-inclusive skincare routine might look like this:

  • Cleanse
  • Tone and/or Spritz
  • Serum
  • Moisturize
  • SPF (only during the day)


If you’ve ever even considered buying a serum, you’ve likely stumbled across facial oils only to wonder if these are one in the same. Are oils serums? Are serums oils? Can we settle this debate once and for all? And how do we use each?

Generally speaking, serums target specific conditions on a cellular level, making them a treatment step, while oils are best suited for hydration. “Oils and serums are not the same,” Candace clarifies, finally putting an end to this madness. “Oils are much larger molecules, meaning they are serving the outermost layers of the skin, which makes them more suitable as a moisturizing step. Serums are smaller molecules which are able to penetrate deeper, making them the ‘worker’ ingredient in your skincare regime.” So, always use your serum before your moisturizer, and never as a replacement. Oils go after your serum or moisturizer, and can be used as your moisturizer.

But here’s the real difference; serums are about efficacy, and oils are about the experience. Of course, you still want facial oils that repair and hydrate. But if you want a luxe, pampering experience that makes you feel like you’re smearing a French garden all over our face, then you should look for that experience from an oil, not a serum. Oils are to have a moment, serums are to do a job, and often, the best serums usually don’t soothe or smell delicious or pamper.



We already know that serums can come in infinite varieties. But let’s start here: day and night, because then you can seek out your serums already knowing how and when you’re going to use them, removing at least one layer of guesswork.

Daytime Serums

Typically, daytime serums are lightweight, hydrating, and protecting. You want to be able to elegantly layer them under makeup without slippage and meltage, so they shouldn’t be too heavy or oily. Day serums are meant to protect your skin from environmental damage using ingredients like Vitamin C, antioxidants, and peptides

Antioxidants/ Vitamin C

Antioxidants protect the skin by counteracting free radicals, which are environmental stressors that damage skin cells. Vitamins C and E are some of the most popular antioxidants in skincare, as they typically work together to protect and heal the skin, and ward off wrinkles, fine lines, and dark spots.

 What To Buy: Alto Defense Serum from SkinBetter Science

This is Candace’s favorite Antioxidant/Vitamin C serum because it has “Vitamin C and 17 other antioxidants in a delivery system that coats all parts of the cell to fight free radicals and prevent damage to the skin. It also improves redness and helps to brighten the complexion.”



Peptides are proteins that help build collagen and elastin fibers, so peptide serums aim to increase collagen and smooth fine lines and wrinkles. But peptides can also protect against free radicals and environmental damage, which is why we like to use them during the day.

What To Buy: PCA Skin Total Strength Serum

This multi-peptide serum has hyaluronic acid and epidermal growth factor to stimulates collagen and helps reduce fine lines (in addition to protecting the skin). It’s lightweight and no-fuss, which makes it a very easy place to start if you’re beginning to dip your toe into the waters of daytime serums.


Nighttime Serums
The PM skincare routine is when you can finally introduce all of those thick, gloopy formulas with 90% retinol (*we’re kidding. Please do not put that on your face*) and give them a solid 7-9 hours (ideally) to do their work. Some stronger formulas, like retinols and acids, are typically recommended at night because they can react with the sun.

We’re condensing nighttime serums into, what we believe are, the 3 most important/all-encompassing PM serum categories.


Retinols are the multi-tasking best friends of aestheticians and dermatologists everywhere. Retinols encourage cellular turnover and collagen production, and retinol serums are potent heavy hitters, treating everything from acne to wrinkles to scarring to dark spots. 

What To Buy: AlphaRet Overnight Cream from Skinbetter Science

We know, it says “cream” in the name, which is confusing, but it’s a serum. Candace loves this retinol serum because it “improves skin texture and color while still lightly hydrating. The formula also delivers these potent ingredients to the skin with little to no irritation, meaning you aren't going through a crazy adjustment phase as you probably have when trying a prescription or OTC retinol product.” 


Exfoliating / Brightening

Exfoliating and brightening serums usually use skin-safe acids to generate cell turnover and slough off dead skin cells, revealing brighter, newer skin underneath. These also work well for acne, aging, scarring, and dark spots.

What To Buy: iS Clinical Active Serum

Another Candace favorite, this serum uses naturally derived exfoliants to “brighten the skin, improve texture, improve acne and congestion, and combat lines and wrinkles.” Candace believes that if you only have the patience to pick one, do-it-all serum, this is it.



Sometimes, your emollient-rich moisturizer and thick facial oil aren’t doing the trick, in which case you need a highly active serum to bind water to your skin. We recommend looking for formulas with ultra-hydrating ingredients like hyaluronic acid and squalane, and prefer to use them at night to give them plenty of time to work their magic.

What To Buy: iS Clinical HydraCool Serum

For some extreme hydration, Candace recommends this serum, which she describes as “a big drink of water for the skin.” It uses hyaluronic acid, which is known to hold 1000x its weight in water, and it works for every skin type.

We know. That was still a lot of information. But here’s what we recommend; for each time of day, pick ONE category (like retinol, exfoliating, or hydrating) that you think your skin needs the most, and then just pick ONE serum to try. Start there. See how it goes.

If you become a serum addict, then by all means, please come back for more. We’ll be here. 

April 02, 2020 — Candace Marino