Vitamin C is well known for its glow-giving effect while leaving skin with an even texture, tone, and youthful vitality. 

What is vitamin C?

Vitamin C, technically known as L-ascorbic acid, is synonymous with skincare. L-ascorbic acid is the purest form of vitamin C and the most available antioxidant in human skin. However, humans cannot produce vitamin C on their own since they do not have the specific enzyme called L-glucone-gamma lactone oxidase-which is needed for its biosynthesis. Therefore, vitamin C is considered an essential dietary component. 

The flip side of dietary or oral vitamin C intake is there is no way to guarantee those vitamin C goes directly to the skin. But recent research reveals skin receives the maximum benefits of vitamin C when applied topically. So, many believe using serums and other skincare products with vitamin C is the most effective way to reap its benefits when it comes to skincare.

Vitamin C & Its Derivatives

L-ascorbic acid is the most biologically active and science-backed form of vitamin C. Unfortunately, L-ascorbic acid is highly unstable and quickly loses its natural properties, including antioxidant activity, when exposed to heat light, and air. To improve the stability of the formulations, most skincare companies use different vitamin C derivatives. However, according to the white papers published, these vitamin C derivatives are not equally effective. Some vitamin C forms do not penetrate the deeper layer of the skin-dermis at an optimal level. And, some do not convert to the biologically active form of vitamin C in the skin. For example, the magnesium salt of vitamin C -Magnesium Ascorbyl Phosphate (MAP), the most stable derivative, penetrates the skin poorly. So, MAP is less effective than L-ascorbic acid. MAP is also a powerful antioxidant that helps protect the skin from UV-induced damage and promotes collagen production while hydrating the skin. Sodium Ascorbyl Phosphate (SAP) also boosts collagen; in-vitro data shows that it works but is less potent than MAP. An oil-soluble form of vitamin C -Ascorbyl Palmitate has no data yet to show it converts to ascorbic acid in the skin. Other commonly available vitamin C derivatives include Ascorbyl Tetra-Isopalmitate, Ascorbyl Glucoside, and Ascorbyl 2-Phosphate 6-Palmitate. 

Benefits of Vitamin C in Skincare

  • Skin brightening & anti-pigmentation effect
    Melanin is the pigment that gives human skin its color. When skin exposes to sunlight, the melanin absorbs UV as they pass through the upper layers of the epidermis and create a protective coat leaving our skin tanned. Topical vitamin C helps fade dark spots and other discoloration while brightening the complexion by inhibiting the action of the enzyme tyrosinase. 
  • A potent antioxidant
    When the skin comes to contact with UV rays, free radicals like Reactive Oxygen Species (ROS) are produced endlessly. These free radicals are unstable and highly reactive chemical species that bind to vital and sensitive molecules such as proteins (collagen.), fats, and other tissues causing structural damage and eventually premature skin aging. The antioxidant activity of L-ascorbic acid protects the skin from oxidative stress by fending free radicals. 
  • Anti-aging effect
    Collagen provides structural support to the skin. These building blocks start to break down as we age, leading to wrinkling and other typical signs of skin aging. Topical vitamin C is thought to stimulate and promotes collagen production quantitatively and qualitatively. The result is a visible reduction in fine lines and wrinkles.

    In addition, vitamin C helps speed up wound healing and prevent post-inflammatory hyperpigmentation (Ex: acne scars).

What experts say

Although Vitamin C alone can provide photoprotection, it works best in both vitamin C and E (Alpha-tocopherol) products because of synergistic antioxidant activity.

Pairing vitamin C with benzoyl peroxide products is not advised as they can counteract each other’s effects: The benzoyl peroxide can oxidize vitamin C.

Also, it is highly recommended to slather a broad-spectrum sunscreen SPF 30 or above after applying vitamin C for greater UV protection.

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