Vitamin C

Vitamin C is considered a stable and effective antioxidant for skin. For skin lightening, several studies have shown it can have benefit for inhibiting melanin production. What complicates the issue of vitamin C is that the vitamin has many forms, and these are used in skin-care products in a wide variety of concentrations. Some of the options may be magnesium ascorbyl phosphate, L-ascorbic acid, ascorbyl glucosamine, and ascorbic acid. While the amount of research isn’t definitive the vitamin offers other benefits along with its skin-lightening ability. Still, there are very few studies showing any of these to have benefit for inhibiting melanin production and the tests that do exist used concentrations far greater than what shows up in most skin-care products. Generally the amount of vitamin C in these studies ranged from 5% to 10%, while most skin-care products containing vitamin C use less than a 1% concentration. (Source: International Journal of Dermatology, August 2004, pages 604-607.)