Vitamin C has become an increasingly popular ingredient in cosmetic skin-care products. In 1992, Dr. Sheldon Pinnell of Duke University published the results of a study that proved the vitamin-C form of L-ascorbic acid reduced sun damage. This launched further studies that proved vitamin C’s other positive effects on the skin. Now, in the cosmetics world, vitamin C is a star ingredient in facial serums.

Vitamin-C Basics

Vitamin C is crucial to the body’s immune system, and serves as an aggressive free-radical fighter. Humans are one of the few animal species that cannot produce vitamin C internally, and must incorporate it into diets and supplements to ensure it can perform its many beneficial functions in the body. It reaches every cell of the body and fights off immune-system invaders, while also playing a key role in the body’s connective tissue. It contributes to the cardiovascular system, facilitates fat metabolism, protects tissues from free-radicals, and assists the nervous system. Vitamin C’s protective abilities greatly benefit the teeth, bones, and skin.

Skin Benefits

Vitamin C is a prime ingredient of collagen, the substance that binds cells together. Collagen metabolism and production is are key attributes of healthy, radiant, younger looking skin. Collagen ingredients and ingredients that promote collagen production are widely used and advertised in body and skin care products. Collagen, in fact, depends on vitamin C, which implies the vitamin’s importance to healthy, attractive skin. Stable collagen production fights wrinkles, and ensures evenness in the skin’s tone and texture.

Vitamin C’s function as an antioxidant also benefits the skin, as it is able to protect the skin from damaging free radicals.

Topical Application

All vitamins are subject to oxidation when used topically, meaning that the vitamins lose their potency (sometimes drastically) when exposed to the air. Therefore, scientists have had to develop ways to incorporate vitamins into skin-care products without the risk of degradation, so that they can provide as many benefits as effectively as possible. Vitamin C is included in skin-care products in the form of its derivatives, which include L-ascorbic acid, ascorbyl palmitate, and magnesium ascorbyl phosphate. These derivatives of vitamin C make it possible for consumers to benefit from the protein’s topical application.

Topical Uses and Benefits

Vitamin C is used in skin care as a strong antioxidant, especially in regard to protecting the skin from sun damage. It strengthens the skin barrier and thickens the dermis. It can expedite the healing of wounds and reduce inflammation. In high concentrations, it can reduce the appearance of skin discoloration. Most important, it promotes collagen production, which subsequently plumps the skin and lends it radiance and smoothness. Dermatologists often use vitamin-C products to enhance the effects of cosmetic treatments, such as microdermabrasion and chemical peels.

Facial Serums Versus Moisturizers

A facial serum is not the same as a facial moisturizer, and most cosmetic skin-care lines offer (and recommend) both. A serum, often lighter and thinner in consistency compared to a moisturizer, is applied to the face after cleansing, and before the moisturizer. Serums usually have specific functions, such as anti-aging or free-radical protection. Serums are able to penetrate deep into the skin layers, while moisturizers address only the superficial surface tissue and its condition.

Serums with Vitamin C

A facial serum with vitamin C provides the most benefit in the vitamin’s topical application. In one of its derivative forms, vitamin C will penetrate the surface layers of the skin to deliver its collagen-stimulation benefits, and protect the skin from damaging environmental factors, like ultraviolet rays.


While vitamin C provides sun-protection benefits, its topical application, as in a facial serum, is not a substitute for sunscreen protection. A moisturizer with an SPF, or a separate SPF lotion should be applied daily.