What to Look For When Shopping For the Most Potent Form of Vitamin C

Vitamin C is the antioxidant of choice for those looking to brighten their skin, help with collagen production, reduce inflammation, and protect skin from environmental aggressors.

Vitamin C is in serums, eye creams, moisturisers, and even face masks. If you peek at the product labels, you'll likely see ascorbic acid or L-ascorbic acid listed. This is vitamin C in its most pure and potent form.

L-ascorbic acid is one of the most naturally active forms of vitamin C, and also one of the most unstable — meaning it can oxidize (or go bad) quick. The stability of vitamin C depends on its pH level — the lower the pH, the more stable it is. Other relatively stable forms of vitamin C are magnesium ascorbyl phosphate, sodium ascorbyl phosphate, and tetrahexyldecyl ascorbate.

Topical vitamin C concentrations can typically range up to a potent 20 percent, and there's debate between experts on what exact percentage is needed to actually absorb into the skin. But, if you're a first-timer, look for something in the 5-10 percent range and give your skin time to adjust.

Now that you have a better idea of the different forms of vitamin C, watch the latest episode of POPSUGAR's beauty explainer series The Makeup for more vitamin C tips and product recommendations from our resident beauty expert, Kirbie Johnson.