Vitamin C is a water-soluble vitamin found in citrus fruit, but don’t go putting slices on your face just yet. That’s not how you’re going to buff up your skin’s defense system against the environment because this is a case where application supersedes digestion. (And you’ll just pee out the extra vitamin C you ingest.)
Your skin’s gonna love this: As the first line of defense against the sun, your skin bears a lot of the brunt of oxidative stress. Vitamin C is like an ally in the army, helping your skin fight sun damage, wrinkles, and abnormal pigmentation. It’s able to fade existing pigmentation and brighten skin tone. You might also see a decrease in fine lines and wrinkles due to its ability to increase collagen formation.
Where to find it: Look for ascorbic acid in the ingredient list. The best follow-up ingredients in the product should be vitamin E (tocopherol) and ferulic acid, two other antioxidants that help stabilize it.
Vitamin C is a powerhouse antioxidant that is known for its unparalleled ability to target hyperpigmentation and prevent pigmentation. It also has anti-inflammatory properties and helps fight free radical damage!
While some skincare ingredients are shrouded in obscurity, others are much more familiar—one of the latter being vitamin C. It's so ubiquitous in brightening products and treatments that whether you're just dabbling in skincare or you're the friend everyone texts for advice, we're willing to bet you've heard of the powerful antioxidant. But if you have yet to incorporate a vitamin C product into your skin routine, allow us to convince you of the many reasons why you should.
INGREDIENT NAME: Vitamin C
TYPE OF INGREDIENT: Antioxidant
MAIN BENEFITS: Protects against free radical damage, evens skin tone, and promotes collagen production.
WHO SHOULD USE IT: Vitamin C is not recommended for those with extremely sensitive skin and can be problematic for those with oily skin. Herrmann recommends asking your board-certified dermatologist which brand may be best suited for your skin type.
HOW OFTEN CAN YOU USE IT: Herrmann recommends using vitamin C daily or every other day.
WORKS WELL WITH: Vitamin C works well with complementing antioxidants like, vitamin E and ferulic acid, which will boost the efficacy and stability of the molecule.
DON'T USE WITH: According to Herrmann, avoid it using with benzoyl peroxide, which can oxidize the vitamin C and make it useless very quickly. Also avoid using it with other acids, which may cause excessive skin irritation, especially if used daily. And lastly, don't it use with retinol, which can make the vitamin C more unstable and less likely to penetrate the skin.1
According to Robinson, vitamin C is an essential nutrient required for the growth and repair of tissues in all parts of the body, including the skin, but we cannot produce it on our own. The powerful antioxidant is found naturally in fruits and vegetables and commonly produced synthetically in skincare products, such as moisturizers, toners, and, most often, serums.1
"It is important to note that vitamin C has both active and inactive forms, Guanche explains. "Depending on the skin care formulation, applying vitamin C can do absolutely nothing or can work as a powerful antioxidant." The first form of vitamin C worth mentioning is the pure form, L-ascorbic acid. Herrmann says this is the most biologically active and well-studied form of vitamin C, but there are also several vitamin C derivatives, such as sodium ascorbyl phosphate, ascorbyl palmitate, retinyl ascorbate, tetrahexyldecyl ascorbate, and magnesium ascorbyl phosphate.
Vitamin C is an impressive skincare ingredient that is shown to be effective in the following areas:
Generally, vitamin C is safe for daily use. However, in high concentrations, it can be irritating, especially if mixed with other acids.5 Herrmann says those with extremely sensitive skin may not be able to tolerate it, and in which case, should avoid it. Many vitamin C products are also oily, which can be problematic for those with oily skin, so Herrmann recommends consulting your board-certified dermatologist to find a brand or product that is best suited for your skin type.
One highly debated topic when it comes to vitamin C is what time of the day is best for application. While some argue that morning is best for protecting the skin, others are in favor of night time when the skin's vitamin C is most depleted. According to Herrmann, consistency is most important, whether you decide to apply it in the morning or before bed, but avoid using it at the same time as benzoyl peroxide. She also suggests using it daily or every other day, and if you're using a serum (the most common vehicle for vitamin C), apply it after cleansing.
As great as it is, vitamin C isn't without obstacles. First of all, it's inherently unstable and reactive and easily loses its antioxidant properties when exposed to heat, light, and air. As a fix, cosmetic companies have been jumping on the powder form of vitamin C to help improve stability, which would, in theory, make it last longer and increase the shelf life.
Unfortunately, though, Herrmann says it’s not as simple as just mixing one part C-powder to one part your favorite moisturizer; Vitamin C also does not easily penetrate the skin's barrier.4 "Depending on the skin care formulation, applying vitamin C can do absolutely nothing or can work as a powerful antioxidant," adds Guanche.
To be effective, Herrmann says vitamin C must be in a concentration of at least 10%, and the pH of whatever you’re adding it to must be acidic to allow for its absorption. "It’s hard to know the pH of products, and even if you get it right, the powder can crystallize on the skin before it has a chance to absorb, which is a must-do for efficacy." For this reason, Herrmann advises against the DIY trend. "I think it’s wiser to stick with high-quality products that have resulted from extensive research and development to make sure their vitamin C is made available in an optimal formulation for enhanced stability and skin penetration," Herrmann says.
Although it can also be consumed orally, Robinson says because of the level of vitamin C necessary for significant skin improvement, it would need to be applied topically. Ingesting it would likely not provide enough.
The typical color of a vitamin C serum is anywhere from a clear to a pale yellow shade. If your serum turns to a very dark yellow, orange, or brown, it's probably a good idea to toss the product.
If your vitamin C serum has turned a golden yellow or brown, it has oxidized. There aren't any studies showing that using oxidized vitamin C will harm the skin, but it will be less effective.
Vitamin C won't necessarily help reduce acne, but due to it's high antioxidant content, it will help decrease redness, irritation, and help treat post-inflammatory hyperpigmentation.