Preventing Sun Damage With Antioxidants
Not all sunscreens are living up to their SPF. Ensure proper sun protection.
A study published in the Journal of Investigative dermatology (1) reaffirms the need for full protection from ultraviolet (UVA and UVB) radiation in sunscreen formulas. The study indicated that ultraviolet radiation (at wavelengths of 280–400 nanometers) inhibits the function of immune cells known to fight skin cancer. However some sunscreens are only offering protection for up to 320 nm, this does not offer any protection from UVA radiation (up to 400nm), which is the primary cause of skin cancer and wrinkles. “Sunscreens are widely advocated to protect against skin cancer but if they offer insufficient protection ... they may inadvertently increase skin cancer risk. This human study evaluated [the immune protection provided] by a commercial sunscreen preparation (labeled sun protection factor 15) offering primarily ultraviolet B (280-320 nm) protection.” It protected against sunburn from the UVB rays, but fell short of shielded the skin from the UVA rays that depletes the skin’s immune system. This study suggested that sunscreens should be formulated to offer full protection from both UVB and UVA rays.
There is also growing research showing that topically applied antioxidants can help protect from sun damage. Antioxidants do not replace the need for sunscreen, however, when used in combination antioxidants are highly effective and a wonderful addition to the protective value of a well-formulated sunscreen (2). Vitamins (especially C and E) have been the topic of several studies on the photoprotective effects of antioxidants when combined with sunscreens. It appears that both vitamins C and E have unique abilities to boost the effectiveness of active sunscreen ingredients, offering better protection from UVA and UVB radiation, respectively. In tests on animal skin, the combination of vitamins C and E with sunscreen proved to offer more protection than sunscreenalone (3). Vitamin A (in the form of retinyl palmitate) has also shown photoprotective effects when used topically. A study on human skin showed that topical application of retinyl palmitate was as
effective at preventing sun-induced redness as a sunscreen rated at SPF 20 (4).
Other antioxidants that have shown protective promise for use in sunscreen formulations include selenium, resveratrol, natural and synthetic astaxanthin, and canosic acid5. Many other antioxidants are being studied as well. Antioxidants also serve as topical anti-inflammatory agents and this is fortunate, because keeping skin inflammation to a minimum is critical to healthy function and outward appearance.
1 Journal of Investigative Dermatology, January 2003, pages 65–71.
2 Source: Journal of Cosmetic Science, November-December 2003, pages 589-598; Cosmetics & Toiletries, August 2002, page 100; and Photodermatology,
Photoimmunology, and Photomedicine, April 2003, pages 56-72.
3 Source: Journal of Investigative Dermatology, August 2003, pages 406-411.
4 Source: Journal of Investigative Dermatology, November 2003, pages 1163-1167.
5 Sources: Toxicology & Applied Pharmacology, Volume 186, Issue 1, January 2003, pages 28–37; Archives of Biochemistry and Biophysics, Volume 412,
Issue 1, April 2003, pages 90–94; Journal of Dermatological Science, Volume 30, Issue 1, October 2002, pages 73–84; and Free Radical Biology and
Medicine, Volume 32, Issue 12, June 15, 2002, pages 1293–1303
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