Yikes: This One Common Mistake Makes Your Vitamin C Serum Lose Its Power
Remember that time we said you should apply serums on damp skin? It's true: Your application matters when slathering on, and a damp canvas makes your hydrating products work 10 times better (especially as the weather gets crisper).
Well, to every rule comes an exception: the notoriously unstable vitamin C, an ingredient you shouldn't really fuss with. It's great for keeping the skin bright and collagen pumping but not so great when exposed to the elements.
Why you shouldn't apply vitamin C serum on damp skin.
Look, vitamin C is hailed for good reason: It has a laundry list of benefits for all skin types, including supporting collagen production, fading hyperpigmentation1, decreasing moisture2 loss, reducing skin inflammation1, fighting against photodamage3, and keeping the complexion bright4—all of which are reduced if you apply it topically on damp skin.
Because along with all the glowing reviews, there's one important rider to mind: Vitamin C degrades and deactivates quickly. It's a water-soluble vitamin, so it loses its potency5 as soon as it's exposed to air, heat, light, and—you guessed it—water. As board-certified dermatologist Julia T. Hunter, M.D., founder of Wholistic Dermatology, puts it: "It starts oxidizing and losing its chemical power."
That's why a vitamin C serum has a relatively shorter shelf life than the other products in your repertoire. (When it starts to visibly oxidize in the bottle, resulting in a yellow-brown substance, it's probably time to toss it.) All that said, you don't want to introduce vitamin C to any more air and water droplets than you already have to (like, every time you open the bottle)—so why would you willingly pat it onto moist skin?
The solution here is simple: Just make sure your face is completely dry before pumping out product. Most experts will recommend waiting 30 to 60 seconds between cleansing and massaging in vitamin C—and if you love a good hydrating toner or essence, perhaps skip the spritz or wait until it completely dries.
Now, if you're a skin care aficionado, you may at this point be thinking, Hey what about all that advice about skin being more permeable when wet? To which we say, Wow you are correct and really know your skin care facts! But even if your skin is more permeable, what's the difference if what you're applying isn't as effective? That's why it is advisable to apply vitamin C on dry skin—and feel free to stick to damp for most of the rest.
Finally, and just as important, following your application you must wait for the product to dry itself. If you don't give your skin adequate time to drink in the actives before slathering on a cream or lotion, you may mix the antioxidant with another ingredient that it doesn't play well with; this, too, will make it less effective.
Unstable actives like vitamin C (and retinoids, too, but that's a story for a different day) shouldn't go on damp skin. While other ingredients (namely, hydrating formulas) fare quite well with a little moisture, vitamin C loses its power when it's exposed to air and water. To really reap the benefits of the beloved ingredient, let's make sure you have a dry canvas.
Jamie Schneider is the Beauty Editor at mindbodygreen. She has a B.A. in Organizational Studies and English from the University of Michigan, and her work has appeared in Coveteur, The Chill Times, and more. In her role at mbg, she reports on everything from the top beauty industry trends, to the gut-skin connection and the microbiome, to the latest expert makeup hacks. She currently lives in Brooklyn, New York.