As a kid, vitamin C likely made its way into your a.m. routine through the glass of O.J. your mom forced you to gulp down before school. Now, as an adult, it should be considered just as integral to your mornings—only this time, you ought to be using a vitamin C serum on your skin for serious brightening benefits.

“Vitamin C is a great skin-care ingredient because it’s safe to use on any skin type and has a ton of incredible anti-aging, hydrating, and brightening benefits,” says Shuting Hu,  cosmetic scientist, formulator, and founder of Acaderma Skincare. The ingredient is a mainstay in cleansers, moisturizers, and masks, but in order to harness its full skin-transforming properties, you’ll really want to integrate it into the treatment step of your routine. The reason? Serums offer a whole lot more bang for your buck. Keep reading to find out why.

Vitamin C serum benefits

1. Protects against environmental aggressors

Vitamin C is one of the most potent skin-care antioxidants on the market, which means that it helps to protect you from something called oxidative stress—one of the main culprits behind signs of aging. Environmental stressors introduce free radicals onto your skin, which degrade your collagen reserves and cause dull, saggy skin. Antioxidants, like vitamin C, work to gobble up those free radicals before they can do any damage. “Think of antioxidants as the protection that you apply before you head out into the world and are faced with all the components of the external world that contribute to aging skin like UV light, pollution, stress, and heat,” says Corey L. Hartman, MD, a board-certified dermatologist and the founder of Skin Wellness Dermatology in Birmingham, AL. “So antioxidants, like vitamin C  are essential components of a good skin care regimen focused on anti-aging.”

2. Fades hyperpigmentation

In addition to the short term defensive benefits of vitamin C serum, you’ll also get the added perk of a more even skin tone. “The vitamin is great for fading pigmentation, reducing redness, and evening out your skin tone, which will help your skin have a more youthful appearance,” says Dr. Hu. Thanks to its antioxidant prowess, it can decrease the production of melanin—which causes dark spots—in your skin. As Dr. Hartman puts it, “the best way to cause your skin to start sagging and develop spots is to skip the vitamins,” so be sure to use yours every morning.

3. Brightens complexion

When you see a product that touts itself as “brightening,” chances are that it contains vitamin C. Because oxidative stress can lead to dullness, the fact that vitamin C fights off that oxidative stress before it can leave its mark will help to give you an even, inside-out glow.

4. Aids in hydration

Though you still need your usual hydrating ingredients, like ceramides and hyaluronic acid, to moisturize your skin, vitamin C can help those ingredients work up to their full potential. “A vitamin C serum decreases transepidermal water loss,” explains Dr. Hu, which means that it helps to seal moisture beneath the surface of your skin to keep it from evaporating  into the environment. Strengthening your skin barrier—which vitamin C serum does—is tantamount to keeping your skin hydrated and healthy, so think of your daily antioxidant application as a mini workout for your complexion.

5. Smooths fine lines and wrinkles

While vitamin C isn’t quite as effective in the anti-aging department as, say, retinoids and peptides, it does help to stimulate your skin’s natural collagen production. This is important because as we age, this natural collagen production slows down. Adding an ingredient that will kick the system into gear can aid in reducing the appearance of fine lines and wrinkles. “Collagen production peaks at age 22 and decreases every decade thereafter, so it is imperative to produce and prevent breakdown of as much as possible,” says Dr. Hartman. Vitamin C helps to curb that degradation by keeping free radicals at bay, and the result is a smoother complexion overall.

Why serum is the best way to get your vitamin C

You can find vitamin C in a whole range of different skin-care products, including cleansers and moisturizers, but serums are the best way to get the most bang for your buck out of the ingredient. “The main reason I prefer serums to moisturizers is that they contain fewer fillers and thickeners,” says Dr. Hu. “Serums are more potent than a cleanser or moisturizer so using a vitamin C serum will deliver the benefits to your skin more directly.” Because serums tend to have higher concentrations of actives (and, as Dr. Hu mentioned, lower concentrations of other stuff), your skin will receive peak amounts of vitamin C.

What’s more? “The molecular size of a serum lends itself to better penetration and absorption than a lotion or moisturizing cream, so it absorbs deeper into the dermis where the fibroblasts that produce collagen and elastin reside,” says Dr. Hartman. Plus, unlike cleansers which are washed away after only a few seconds, a serum sits on your skin all day so that you’re able to reap the benefits of their vitamin C for hours at a time.

What to look for in a vitamin C serum

Vitamin C can be a fickle ingredient, so you’ll want to be sure you know what to look for when you’re looking for a serum. First things first: Since vitamin C is sun sensitive (which means it can oxidize and become less effective when it’s exposed to the sun), you’ll want to seek out a product in a dark or tinted bottle. On its own, it also tends to be unstable, so your best bet is to find a formula that pairs vitamin C with another stabilizing molecule. “It works really well with vitamin E, which stabilizes vitamin C for maximum skin protection,” says Dr. Hu. “Ferulic acid also works well with vitamin C, because it will help lower the vitamin C’s pH level so your skin has an easier time absorbing the serum.”  Since vitamin C can be irritating on its own, these supplemental ingredients also help to make vitamin C serums more tolerable for sensitive skin types.

As far as concentrations go, Dr. Hu recommends using something that contains at least 8 percent vitamin C, adding that the sweet spot falls somewhere between 10 and 20 percent. You should also be aware that products that label themselves as vitamin C may only include a vitamin C derivative—which isn’t as potent as the real deal—so you’ll want to check the label to be sure you’ve got the right stuff. “Look for L-ascorbic acid, which has the most skin-related research of any form of vitamin C,” says Dr. Hartman. “When properly formulated at a pH of less than 4—2.6-3.2—is the ideal range), this form helps create younger-looking, firmer-feeling skin while fading signs of uneven skin tone and spots.”

How to use a vitamin C serum

Since vitamin C is your skin’s first line of defense against the elements, you’ll want to use it every morning for optimal results. “I recommend using a vitamin C serum after cleansing your skin and then following up with a moisturizer to maximize the benefits of the product,” says Dr. Hu. “Just remember vitamin C does become less effective when exposed to light so wait a few minutes to let the serum fully absorb into the skin before heading out.” And of course, always be sure to follow it up with your favorite SPF so your skin will be fully protected.

The best vitamin C serums, according to pros

Skinceuticals CE Ferulic — $166.00

This serum has long been known as the gold standard in the vitamin C market, and it’s well worth its hefty price tag. It checks all the boxes that derms recommend looking out for—it’s pairs a 15 percent concentration of pure vitamin C with vitamin E and ferulic acid and comes in an opaque, air tight bottle—and won’t irritate dry skin.

SkinBetter Alto Defense — $220.00

For something extra gentle, yet effective, Dr. Hartman recommends this lotion. “It gently hydrates and works well for all skin types,” he says. It’s got your usual vitamins C and E, plus 17 other antioxidants, which means you can walk out of the house every morning knowing your skin is properly protected.

LaRoche-Posay 10% Pure Vitamin C Serum — $31.00

You’re in luck: One of the best vitamin C serums out there happens to be available at the drugstore. “LaRoche-Posay 10 percent Pure Vitamin C Serum is an affordable option that leaves skin protected and radiant without irritation,” says Dr. Hartman.

Acaderma Invisible Shield Defense Serum — $80.00

“I recommend applying this serum in the morning to protect your skin from damaging infrared and blue light, free radicals, and pollution,” says Dr. Hu. “It contains a powerful antioxidant derived from sesame seeds and is combined with 11 other clinically proven actives, including peony, summer snowflake, gold seaweed, ribose, and resveratrol.” Use it every day, and you’ll see the diminished appearance of fine lines and wrinkles, too.

Native Atlas Zahara Vitamin Serum — $60.00

This energizing serum will help ramp up your skin barrier’s defense mechanisms and leave you positively radiant. “It soaks deep to even skin tone, reduce discoloration, and most importantly restore and protect your skin barrier,” says Dr. Hu. It’s made with nourishing plant botanicals that hydrate and heal the skin, plus baobab seed oil, which is known as”the tree of life” thanks to the fact that its packed with vitamins C, D, and E and essential fatty acids that help to stimulate cell regeneration and improve skin elasticity.

For more intel on the benefits of vitamin C serum, check out the video below. 

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