Vitamin C : skin food
Vitamin C is a naturally occurring active substance with multiple uses such as photoageing, hyperpigmentation, tissue inflammation and promotion of tissue healing. Humans lack the enzyme required for synthesis of Vit. C; hence, they must acquire it from natural sources such as citrus fruits, green leafy vegetables, strawberries, papaya and broccoli.
The bioavailability of Vit. C in the skin is inadequate when it is administered orally. The use of topical ascorbic acid is therefore favored in the practice of dermatology.
BENEFITS OF VITAMIN C IN SKIN
1.- Antioxidant action:
Vit. C, is one of the most plentiful antioxidants that co-exist to protect the skin from reactive oxygen species. Vit. C protects the skin from oxidative stress by sequentially donating electrons to neutralize the free radicals.
2.- Collagen synthesis:
Vit. C stimulates collagen synthesis increasing collagen production in young as well as aged human skin as well as stimulating qualitative changes in the collagen molecule.
3.-Pigmentation:
Vit. C decreases the melanin formation. However, Vit. C is an unstable compound. It is therefore often combined with other depigmenting agents such as liquorice for better depigmenting effect.
4.- Anti-inflammatory:
Vit. 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.
TOPICAL FORMULATIONS OF VITAMIN C
From a clinical point of view, it is important to note that the efficacy of the Vit. C serum is proportional to the concentration, but only up to 20%. A persistent reservoir of Vit. C is important for adequate photoprotection, and can be achieved by regular 8-hourly applications.
Some froms of vitamin C in the market are not delivered into the dermis in an adequate quantity, while others do not chemically convert to the biologically active form of Vit. C in the skin.
Magnesium ascorbyl phosphate (MAP) is the most stable and preferred ascorbyl ester. It is easily absorbed into the skin. MAP has a hydrating effect on the skin and decreases transepidermal water loss. It is also a free radical scavenger that is photoprotective and increases collagen production under laboratory test conditions. Other useful stable esterified derivatives are: ascorbyl 6 palmitate, disodium isostearyl 2-0 L-ascorbyl phosphate , ascorbic acid sulfate, and tetraisopalmitoyl ascorbic acid.
Topical Vit. C is largely safe to use on a daily basis for long durations. It can safely be used in conjunction with other common topical anti-ageing agents such as sunscreens, tretinoin, other antioxidants and alfa hydroxy acids such as glycolic acid. Care must be taken while applying Vit. C around the eyes.
Talakoub L, Neuhaus IM, Yu SS. Cosmeceuticals. In: Alam M, Gladstone HB, Tung RC, editors.Cosmetic dermatology. Vol. 1. Requisites in Dermatology. 1st ed. Gurgaon: Saunders Elsevier; 2009. pp. 13–4. [Google Scholar]
Traikovich SS. Use of Topical Ascorbic acid and its effects on Photo damaged skin topography.Arch Otorhinol Head Neck Surg.1999;125:1091–8.[PubMed][Google Scholar]
Farris PK. Cosmetical Vitamins: Vitamin C. In: Draelos ZD, Dover JS, Alam M, editors. Cosmeceuticals. Procedures in Cosmetic Dermatology. 2nd ed. New York: Saunders Elsevier; 2009. pp. 51–6. [Google Scholar]
Wikepedia: [Home Page] Vitamin C: History. [Last Accessed on Aug 11]. Discovery and Sources in Available from: http://en.wikipedia.org/wiki/Vitamin_C
Telang PS. Vitamin C in dermatology.Indian Dermatol Online J. 2013;4(2):143‐146. doi:10.4103/2229-5178.110593