As a powerful antioxidant (which helps prevent and reduce skin cell damage) that also lightens hyperpigmentation and helps smooth fine lines, there’s a lot to love about vitamin C. But there are a few important points you’ll want to consider when choosing—and using—a vitamin C product.
Look for this specific kind of vitamin C.
First, be aware that vitamin C is really more of an umbrella term. Just as there are different types of retinoids, there are lots of different kinds of vitamin C. Generally, experts agree that L-ascorbic acid is the most effective of them all. It’s the most biologically active, which means that your skin can use it immediately.
But. It’s not quite that clear-cut. For one, L-ascorbic acid is also the least stable of all the vitamin C variants, so it degrades quickly when it’s exposed to light, air, and heat. And while it does penetrate the skin well, that’s only when it’s formulated in a product that has an acidic pH of about 3.2. Even more, a pH of that level means an increased likelihood of irritation, especially for those with sensitive skin.
One last caveat: L-ascorbic acid is water-soluble, so stick with serums. They’re far more effective than creams and moisturizers.
Hone in on the product label.
Beyond the type of vitamin C, you’ll also want to take notice of its concentration. Which you should be able to find easily on the product’s label. If you can’t, vitamin C should be one of the first three or four ingredients listed. Otherwise, the vitamin C is too diluted to have any effect.
Vitamin C products usually come in concentrations of five, 10, 15, and 20 percent. If you’re new to them, start at 10 percent and increase gradually, as tolerated.
The packaging matters, too.
Remember the part above about L-ascorbic acid being very unstable? Well, all forms of vitamin C are susceptible to some degradation when exposed to light and air. For that reason, only buy vitamin C products that are housed in dark, opaque glass bottles. And make sure to store them in a drawer or cabinet, away from heat and light.
Effective products probably won’t be cheap.
“You get what you pay for” doesn’t always hold up with skincare products, but it does where vitamin C is concerned. A well-formulated product with L-ascorbic acid is probably not going to be cheap. The reality is that it’s expensive to manufacture vitamin C products properly.
Stick with short ingredient lists.
Finally, you’ll also want to be mindful of how vitamin C interacts with other ingredients. It plays particularly well with other antioxidants, like vitamin E and ferulic acid. Beyond those, vitamin C can be pretty finicky. So opt for products with short ingredient lists, especially where L-ascorbic acid is concerned. The more ingredients there are in a formula, the less likely it is the product will be at the pH level that’s necessary for vitamin C to be effective.
In that vein, you should also avoid using your retinoid and vitamin C products together. Retinoids work better at a higher pH level, and the discrepancy can render both inactive. Go with vitamin C in the morning and retinoids at night.