While there is a lot of research in this field, so far, there's no solid proof that topical antioxidants slow aging and prevent or reduce skin wrinkling. However, there is some evidence that preparations containing vitamin C, vitamin E and selenium can help repair sun-damaged skin. Here's a quick rundown on what recent studies have shown:
- Vitamin C: Applying topical vitamin C 15 to 30 minutes after sun exposure prompts repair of damaged skin. In an animal study, topically applied vitamin C minimized damage from chronic exposure to ultraviolet light.
- Vitamin E: A number of studies have found that topical natural vitamin E (d-alpha-tocopherol) can lessen sunburn AND reduce UV-induced damage, including occurrence of cancerous cells.
- Selenium: This antioxidant mineral appears to preserve tissue elasticity and slow the aging and hardening of tissues due to oxidation. Recent animal studies have shown that taken orally or applied topically in the form OF L-selenomethionine, selenium protects against both daily and excessive UV damage, with less burning after exposure.
Your question about adding powdered vitamin C to a moisturizer,as a low-cost substitute for antioxidant skin creams is an interesting one. I consulted my colleague Sam Benjamin, MD, an authority in the field. He told me that the preparation you propose would lack proper consistency, resulting in poor control of the concentration of the antioxidant and its speed of absorption into the skin. The best commercial products contain other ingredients that enhance absorption, prevent the vitamin C from oxidizing, and maintain a consistent bioavailability to the skin.
Despite the studies mentioned above, evidence for the efficacy of topical antioxidants is preliminary. Your best bet may be to wait until we know more about how well they work before you invest in the expensive skin products. If your goal is to prevent or reduce wrinkling and sun damage to skin, you would be better off with proven treatments such as alpha-hydroxy acids (AHAs) or Retin A (tretinoin). (Dermatologists have long been using topical derivatives of vitamin A, collectively known as retinols, for a number of skin problems, especially acne and the reversal and prevention of sun damage.)
And, of course, the most effective way to deal with skin problems is to prevent their occurrence in the first place by avoiding the sun damage responsible for wrinkles, age spots and other common problems. Be sure to wear a hat with a brim and protective clothing to shield your skin against the sun's damaging rays and to use an SPF 15 or higher sunscreen whenever you go out at times and places when sunburn is a possibility.
Andrew Weil, M.D.