Vitamin C, or Ascorbic Acid is a naturally occurring substance that is vital to the proper functioning of many human organ systems. It is found abundantly in vegetables and fruits. As we cannot manufacture Vitamin C in our bodies, humans have to either consume it ot apply it onto our skin as topical Vitamin C.
There are many forms of topical Vitamin C serums in formulations out their in the shops. From a dermatological standpoint, magnesium ascorbyl phosphate (MAP) is the most stable and preferred ascorbyl ester in topical applications. This lipophilic molecule is easily absorbed into the skin and is the biologically active form of L-Ascorbic Acid.
So what are the benefits of topically applied Vit C
Topical Vitamin C as an antioxidant
When the skin is exposed to UV light, superoxide ion, peroxide and singlet oxygen are generated. These are collectively called free radicals. Vitamin C protects the skin from oxidative stress by "donating" electrons to neutralize the free radicals. The oxidised forms of Vitamin C are relatively non-reactive. But they can be convert back to Vitamin C by the enzyme dehydro-ascorbic-acid reductase in the presence of glutathione. Hence the combination of Vitamin C and Glutathione is a potent antioxidant pair found in many dermatologic formulations. Including the controversial Skin Whitening IV infusions.
Topical Vitamin C is photo-protective
Vitamin C is not a sunscreen, hence it does not absorb UV light. But it exerts an UV-protective effect by neutralizing free radicals. It works best in conjunction with Vitamin E, which potentiates the action of Vitamin C four-fold. Vitamin C and Vitamin E synergistically limit chronic UV damage by significantly reducing both cell apoptosis and thymine dimer formation. When used in combination with 0.5% ferulic acid (a potent antioxidant of plant origin), the photo-protective properties of Vitamin C is even further enhanced.
This triple combination was very useful for the reduction of acute and chronic photodamage, and could be used for prevention of skin cancer in the future.
Topical Vitamin C treats hyperpigmentation
L-ascorbic acid or Vitamin C is a substance that interrupt the key steps of melanogenesis. Vit. C falls into the latter category of depigmenting agents. d inhibits action of the enzyme tyrosinase, thereby decreasing the melanin formation. Vit. C also acts on the perifollicular pigment. However, Vitamin C is an unstable compound, and the trick to deliver it in optimum amounts and in it active form L-ascorbic acid make it premium item.
Topical Vitamin C is important in collagen synthesis
Working at various levels, Vitamin C is essential for collagen biosynthesis. It influences quantitative collagen synthesis in addition to stimulating qualitative changes in the collagen molecule. Vitamin C serves as a co-factor for the enzymes prolysyl and lysyl hydroxylase, the enzymes that are responsible for stabilizing and cross-linking the collagen molecules. Another mechanism by which Vitamin C influences the collagen synthesis is by stimulation of lipid peroxidation, and the product of this process, malondialdehyde, in turn stimulates collagen gene expression.
Vitamin C also directly activates the transcription of collagen synthesis and stabilizes procollagen mRNA, thereby regulating collagen synthesis. Signs and symptoms of Scurvy, a deficiency disease of Vitamin C, are due to impaired collagen synthesis.
Clinical studies have shown that the topical use of topical Vitamin C increases collagen production in young as well as aged human skin.
Topical Vitamin C is an anti-inflammatory agent
Working through the stabilization of various interferon and cytokine pathways, topical Vitamin C has a potential anti-inflammatory activity and can be used in conditions like acne vulgaris and rosacea. It can promote wound healing and prevent post-inflammatory hyperpigmentation.