When looking at the ingredients list, if you want a pure form of vitamin C, choose a vitamin C serum to use L-ascorbic acid is the main form of vitamin C. “Known as the purest form of vitamin C, L-ascorbic acid helps neutralize free radicals, minimize the appearance of wrinkles, and brighten skin tone.” Mona Gohara, MD, clinical associate professor at Yale.
If you have more sensitive skin or just want a more stable form of vitamin C, Zeichner recommends vitamin C esters instead of the pure form. “Vitamin C esters are an oil-soluble form, which tends to be less irritating and more stable in cosmetic formulations,” he says. “Examples include sodium ascorbyl phosphate and THD ascorbate. Many have steady light and come in clear bottles. “
