Vitamin C in Skincare: What’s the Hype?

Annie Wester, MD, MS, FAAD

 

Vitamin C is a hot topic in Dermatology due to its multifaceted benefits, but not all vitamin C products are created equal. The variety of vitamin C serums on the market and conflicting information about their use makes picking the right one overwhelming. We’ll break down the importance of vitamin C in your daily skin routine and highlight the products with proven efficacy.

 

What is vitamin C?

In scientific terms, vitamin C is an antioxidant that neutralizes free radicals. Free radicals are unstable atoms, created by exposure to triggers such as sun exposure, smoking cigarettes, and air pollution. Free radicals can damage our body’s cells, contributing to multiple health issues, such as atherosclerosis and skin aging.  Vitamin C is also an essential cofactor for biologic processes, including collagen formation and wound healing. Lastly, vitamin C inhibits the production of melanin, the molecule responsible for brown pigment in skin, by blocking the enzyme tyrosinase.

 

How does vitamin C benefit the skin?

Because of these antioxidant & enzymatic effects, when applied to the skin, vitamin C prevents aging induced by sun and environmental exposures, promotes collagen development, inhibits pigment production, and reduces transepidermal water loss. In short, a Vitamin C serum is a great addition to your skin care regimen as it improves sun-induced aging, lightens certain types of brown spots, and moisturizes the skin.

 

What’s with all the different types of vitamin C?

The pure form of vitamin C is known as L-ascorbic acid (L-AA). This is the most biologically active and well-studied form of vitamin C.  However, this form is oxidized, and thus inactivated, quickly in air, heat, light, or extreme pH.  Scientists have stabilized L-AA for cosmetic use by combining it with vitamin E and ferulic acid. Many other formulations of vitamin C exist, including 3-0 ethyl ascorbic acid, ascorbyl glucoside, magnesium and sodium ascorbyl phosphate, tetrahexyldecyl ascorbate, ascorbyl tetraisopalmitate, and ascorbyl palmitate. These derivatives are not pure vitamin C, but contain modifications to increase the stability and tolerability of the ascorbic acid molecule. In terms of efficacy, many of these formulations have conflicting data or need further research to validate their claims. L-ascorbic acid stabilized with vitamin E & ferulic acid, tetrahexyldecyl ascorbate, and ascorbyl tetraisopalmitate have the most data supporting their use. 

 

Which vitamin C product should I use?

Skinceuticals CE Ferulic is the most studied and validated vitamin C product. It is an L-ascorbic acid with vitamin E 1% and ferulic acid 0.5% added for L-AA stability. CE Ferulic’s formula is patented, so no products exist on the market with this exact formulation.

For patients with sensitive skin, Revision Vitamin C lotion 30% is a great option, as vitamin C products can cause mild irritation.  Rather than L-AA, Revision is formulated with tetrahexyldecyl ascorbate, a modified Vitamin C with deeper penetration and less irritation than the pure form. 

Our office carries an excellent product with L-AA and tetrahexyldecyl ascorbate, stabilized with vitamin E, called PuraSkin MD Vitamin C Brightening Serum. This is less expensive than the Skinceuticals product with a more elegant vehicle for application. 

Three other popular products are Skinbetter Alto Defense, Drunk Elephant Vitamin C Day Serum, and Vichy Peptide C.  

 

How should I use vitamin C?

Vitamin C is best applied to the entire face and neck in the morning, followed by a moisturizer with SPF 30 or higher. Vitamin C is inactivated by retinoids and benzoyl peroxide.  If you are using a prescription retinoid (tretinoin, retin-A, differin, adapalene) or an over the counter retinol, be sure to space out the application of vitamin C and these products. I recommend patients apply their vitamin C serum in the morning and their retinoid at night. There are reports that benzoyl peroxide can accelerate skin aging. For this reason, and to prevent inactivation of the vitamin C, ditch your benzoyl peroxide. Salicylic acid is a safe alternative if an acne wash is needed.

Try out a vitamin C product & let us know how you like it. If you have any questions, ask a board certified Dermatologist at your next appointment. 

 

Summary

  • Vitamin C serums prevent photoaging, lighten some brown lesions, and hydrate skin
  • L-ascorbic acid with vitamin E & ferulic acid, tetrahexyldecyl ascorbate, and ascorbyl tetraisopalmitate are the Vitamin C derivatives that have the most data supporting their efficacy
  • Vitamin C is inactivated by retinoids, so apply your vitamin C serum in the morning and your retinoid at night
  • Recommended Vitamin C products:
    • PuraSkin Vitamin C Brightening Serum ($126)
    • Skinceuticals CE Ferulic ($166)
    • Revision Vitamin C Lotion 30% ($122)
    • Skinbetter Alto Defense ($155)
    • Drunk Elephant Vitamin C Day Serum ($80)
    • Vichy Peptide C ($30)