Vitamin C is a naturally occurring antioxidant with multiple desirable effects. Vitamin C boosts up the immune system, reduces the severity of allergic reactions and helps to fight off infections.
Did you know ,Unlike plants and animals, humans are not able to synthesize vitamin C in vivo due to absence of the enzyme L-glucono-gamma lactone oxidase. So, we must acquire it from rich natural sources such as citrus fruits, green leafy vegetables, strawberries, papaya and broccoli.
L-ascorbic acid (LAA) is the chemically and biologically active form of Vitamin C. In natural sources, Vitamin C is found in equal parts as LAA and D-ascorbic acid. Though these isomeric molecules are mutually interchangeable, only LAA is active and useful in medical practice.
Oral vitamin C
Dietary Vitamin C is important for maintaining normal functioning of the skin during keratinocyte differentiation and collagen formation.
Vitamin C deficiency causes Scurvy which is characterised by skin fragility, bleeding gums and corkscrew hairs and impaired wound healing.
Many studies have shown an increase in skin vitamin C content following supplementation with oral vitamin C. But the absorption of Vitamin C in the gut is limited and only a mere amount of the drug reaches the skin inspite of high oral dosage. Hence the use of topical ascorbic acid is favoured for most skin conditions.
Intake of oral vitamin C decreases lipid peroxidation and increases superoxide dismutase activity, thereby improving the Antioxidant activity.
It inhibits the activation of pro-inflammatory cytokines like TNF-alfa, IL1, IL6 and IL8 and has a potential anti-inflammatory activity. It can be used in conditions like acne vulgaris, rosacea, wound healing and to prevent post-inflammatory hyperpigmentation.
Reduces oxidative stress
UV radiation, pollution, and smoking can accelerate damage to the skin through the generation oxidative stress. Vitamin C is one of the most potent antioxidants in the skin as it neutralizes the oxidative stress by a process of electron transfer and/or donation.
Vitamin C interrupts the key steps of melanogenesis and inhibits the action tyrosinase, the main enzyme responsible for the conversion of tyrosine into melanin and decreases melanin formation. It also acts upon the perifollicular pigment. It is used in the treatment of melasma and dark spots.
Wound healing is a complex process composed of inflammation, new tissue formation and remodelling. Vitamin C has beneficial effect on wound healing which is directly related to its co-factor activity for the synthesis of collagen, and impaired wound healing is an early indicator of hypovitaminosis C.
Loss of collagen and changes to the dermal–epidermal junction may contribute to aging. Vitamin C is an important antiaging agent as it is essential for collagen synthesis.
Protection against photoaging
Free radicals released due to absorption of solar ultraviolet radiation are highly toxic molecules that can damage the cellular nucleic acids, proteins, and cell membranes. These UV-induced reactive oxygen species also trigger matrix metalloproteinases (MMPs) which degrade collagen, reduce collagen production, and increase elastin accumulation. This leads to wrinkles and photoaging. Topical Vitamin C inhibits MMP production and collagen damage and thereby reduces skin wrinkling.
Protects against photocarcinogenesis
UV radiation induced reactive oxygen species cause p53 gene mutations which affect the repair of damaged deoxyribonucleic acid (DNA) and induce programmed cell death (apoptosis). Topical Vitamin C has shown to reduce UV-induced apoptotic sunburn cell formation, erythema and thymine dimers, thereby reducing the risk of photocarcinogenesis.
Restorer of vitamin E
Vitamin E is an antioxidant that protects the cellular contents against oxidative stress and maintains the collagen network in the skin. Vitamin E levels are rapidly depleted after UV exposure. Vitamin C is known to be the primary replenisher of vitamin E.
Vitamin C is essential for the development and maintenance of connective tissues. It protects the body from free radical damage and is used as therapeutic agent in many disorders.