Dermatologists have long recommended vitamin C for brighter, healthier skin. With the rise of the skin care industry, vitamin C serums generate billions in annual sales. But the growing literature suggests that the reality is more complex than marketing claims suggest.
Without a doubt, vitamin C is essential for human skin. Studies have shown that normal skin contains a high concentration of the vitamin, with epidermal levels two to five times higher than in the dermis.
Different roles are associated with this compound, including that of a cofactor for the synthesis of collagen, acting as an antioxidant against the radicals formed by ultraviolet rays, suppressing melanin and stimulating the formation of ceramides, the lipid molecules which bind skin cells together.
However, the real problem lies in the seepage of vitamin C into the skin.
Being a soluble, water-loaded nutrient, it is usually repelled by the skin’s surface. Beneficial penetration only occurs when formulations have a pH below 4.
For better stability and penetration, manufacturers typically use derivatives such as magnesium ascorbyl phosphate, ascorbyl glucoside, and ascorbyl palmitate. However, they must be converted into active vitamin C once inside the skin.
Most serums never penetrate deep enough to work. Those who only have three things, including:
- Pure vitamin C (L-ascorbic acid) at low pH
- Delivered in opaque, airtight bottles to prevent oxidation
- Combine vitamin C with vitamin E often for best results.
But if vitamin C levels are already saturated through diet or oral supplements, topical application may not increase skin levels further.
