Vitamin C serums are one third of the holy trinity of skincare products for a reason: they work. Along with sunscreen and retinol, any dermatologist will be quick to tell you that vitamin C is essential in every basic skincare routine.
So, what makes vitamin C so great? The antioxidant treats a number of common skincare concerns including dark spots, fine lines, wrinkles, and uneven skin texture. While vitamin C is extremely effective, you'll only see results if you're using it correctly. And just like any other skincare ingredient, it comes with some dos and dont's.
Because knowledge is power, we turned to board-certified dermatologists Dr. Michelle Henry and Dr. Lily Talakoub to break down the skincare benefits of vitamin C, along with how to properly incorporate it into your routine.
What Is Vitamin C?
Vitamin C is a powerful antioxidant that neutralizes free radicals, which can lead to premature signs of aging like wrinkles and fine lines. In other words: Antioxidants help keep skin healthy by preventing or reducing damage to skin cells by reactive molecules, aka free radicals. "The antioxidant activity of vitamin C protects against UV-induced damage caused by free radicals, which will prevent accelerated aging and skin cancer," explains Dr. Henry. It also boosts firmness by regulating collagen production.
The antioxidant can be used to treat dark spots and hyperpigmentation. Dr. Henry says that vitamin C can have lightening effects because it interferes with the enzymes used in melanin production.
How Can You Add Vitamin C to Your Routine?
First off, there's multiple forms of vitamin C. Ascorbate and ascorbic acid are naturally occurring forms of the antioxidants, and sodium ascorbyl phosphate is a synthetic, stable, water-soluble form of vitamin C that's produced to use in skincare products.
When shopping for a vitamin C skincare product keep the following in mind: L-Ascorbic Acid is the most beneficial and effective of all forms. However, if acne is also one of your skincare concerns, Dr. Henry says that there's some research that shows sodium ascorbyl phosphate can be effective at treating breakouts when used in one percent and five percent concentrations when incorporated into skincare routines that also include acne-fighting ingredients like benzoyl peroxide.
If you're looking for a vitamin C product that will deeply penetrate the skin, pick one with oil-soluble tetrahexyldecyl ascorbate, a derivative of L-ascorbic acid.
Generally, serums are the most common and popular vitamin C product category, but the ingredient is also found in moisturizers. Dr. Henry says that you can use vitamin C products twice a day, but recommends including one in your morning routine so that you can use retinol at night. (More on that later.)
Dr. Talakoub, on the other hand, likes mixing a few drops of a vitamin C serum into moisturizer for an antioxidant boost. "I like the serum versions which are bound in oil because they are the most stable forms of vitamin C," she says.
VIDEO: Which Anti-Aging Serums to Buy for Your Skin Concerns
What Are the Side Effects of Using Vitamin C?
Unless you have a specific allergy, vitamin C is an ingredient that's safe for all skin types to use. However, there's some ingredients you shouldn't mix with the antioxidant. Using vitamin C and retinol together can cause irritation and deactivate the ingredients, which makes them ineffective. The same goes for exfoliating AHA and BHA acids.
"Retinoids, Retinols, and AHA and BHA acids should not be mixed with vitamin C as their efficacy may be reduced as they function optimally in environments of very different pH levels," says Dr. Henry. That's why she recommends using vitamin C in the morning, and reserving your acids or retinol for nighttime use.
One final note: While vitamin C is highly-lauded, it's notorious for its bad smell. Both dermatologists say that the infamous "stale hot dog water" smell could be caused by the product's combination of ingredients or the vitamin C in it has gone bad. So, make sure you check the expiration date before slathering that serum on your face.