Previous e-mails discussed the different forms of skin aging and the role of Vitamin A. Parts 1, 2, 3, 4 of the series on Antioxidants, Anti-aging and Skin Rejuvenation, can be found on our website www.skincare-md.com. This e-mail discusses the benefits of the antioxidant Vitamin C.

Vitamins C and E are thought of as “healing” antioxidants because they help the skin recover from injuries such as ultraviolet radiation and smoking. L-ascorbic acid is the active form of Vitamin C and is the most abundant antioxidant in the skin.¹ Humans cannot synthesize Vitamin C; therefore, we must rely on dietary supplementation. Humans require Vitamin C for collagen synthesis as well as a number of other bodily functions. The minimal daily allowance for Vitamin C, 60 mg per day, may be adequate for providing the skin with sufficient levels of protection against harmful ultraviolet radiation. Unfortunately, our bodies do not store excess intake. The Vitamin C is absorbed through the skin and concentrations of 15-20% aqueous preparation at a pH of 3.5 (acidic pH) generally lasts about 4 days, providing significant protection against photodamage (ultraviolet radiation). The Vitamin C may absorb both UVA and UVB, improves collagen synthesis and is anti-inflammatory.

An interesting study by Fitzpatrick and Rostan² compared Vitamin C (10% water soluble and 7% fat soluble) with just the base, comparing the two sides of the face in ten patients. Clinical evaluation was done at 4, 8 and 12 weeks, and biopsies were performed at 12 weeks on 4 patients. Results showed that Vitamin C results were clinically visible, and statistically significant improvement in wrinkling noted when used topically for 12 weeks. This correlates with biopsy evidence of new collagen formation.

We have been testing Vitamin C products as serums and creams, as well as for ease of use. As Vitamin C oxidizes (turns yellow, then brown), it appears to lose its effectiveness. Most studies use 10-20% L-ascorbic acid, and it is likely that reputable companies can manufacture effective Vitamin C skin care products. For those who desire the additional protection and therapeutic benefits of Vitamin C as a supplement to their skincare program, we now carry Applied Therapeutics Revitalizing Vitamin C Capsules by NPR. This product contains a stable form of 10% Vitamin C in a dual-encapsulation system which eliminates virtually all degradation of the Vitamin C. We also carry Cffective by Obagi in a 5% (for the eye area or for sensitive skin) and a 10% serum. Studies show that Cffective is stable for 2 years, and once opened, is stable for 12-14 months. It is suggested that Vitamin C be used after your cleanser in the morning and before lotions, creams or sunscreens.

Most studies evaluate the benefit of Vitamin C by itself, isolated from other therapeutic programs. The benefits of adding Vitamin C to an effective skin care program are not conclusive. It is important to remember that no single product is the complete answer to skin rejuvenation. Glycolics are excellent for exfoliation of skin, moisturizers are important for proper hydration of the skin, sunscreens are necessary for protection against damaging ultraviolet radiation, and antioxidant vitamins are beneficial in helping the skin recover from injuries such as ultraviolet radiation (see previous e-mails).