by Craig Weatherby and Linda Sparrow
Growing evidence suggests that the omega-3s from fish can help protect skin from sun damage.
For more on that, see “Dietary Fish Oil Found to Deflect Sun Damage” and “Fish Fats Called Credible Foes of Skin Aging and Skin Cancer.
And there is even more evidence that dietary antioxidants help slow the aging of skin... welcome news that's been spread in several bestsellers by dermatologist Nicholas Perricone, M.D.
Many studies indicate that oral doses of vitamins C and E, which possess antioxidant properties, provide some protection against sunlight.
And research indicates even more skin-protective benefits may flow from consumption of a particularly potent class of antioxidants called flavanols, which abound in berries, grapes, tea, red wine, and cocoa (See “Edible Sunscreen? Colorful Foods Seen to Deter Sun Damage”).
In addition to neutralizing skin-cell-damaging free radicals, antioxidants turn off genetic switches that can perpetuate a cycle of free radical-driven inflammation, which in turn generates more free radicals.
This, loading up on antioxidant-rich foods should help prevent skin damage and the fine lines and wrinkles that follow.
Two years ago, German researchers penned this succinct summary of the abundant research conducted on this topic:
“Plant constituents such as carotenoids and flavonoids are involved in protection against excess light in plants and contribute to the prevention of UV damage in humans… they are [naturally] distributed into light-exposed tissues, such as skin or the eye where they provide systemic photo-protection” (Stahl W, Sies H 2007).
By “photo-protection,” they meant protection of skin against excess sunlight. And carotenoids and flavonoids belong to the larger antioxidant family called polyphenols.
While they can't substitute for sunscreen, new research from Korea supports the notion that food-borne antioxidants offer substantial protection from sun-related skin aging and wrinkle formation.
Korean study finds berries benefits human skin cells and live mice
Researchers at Hallym University in Korea conducted a two part study, whose results support the skin benefits of berries.
First, they exposed human skin cells to a polyphenol antioxidant from berry extracts, called ellagic acid, and then to UVB rays like the ones in sunlight that cause skin aging.
The berry-derived ellagic acid blocked production of MMP (matrix metalloproteinase) enzymes that break down collagen in damaged skin cells and reduced production of ICAM (a molecule involved in inflammation).
In the second part of the study, they applied berry extract topically to one of two groups of hairless mice, but not to the other. (Performing tests on mice is commonly done because of the likeness of their skin to that of human's.)
The researchers then exposed the two groups to UV rays that were sufficient to cause skin damage in humans.
As hoped, the mice smeared with berry extract suffered less skin damage… it deterred collagen destruction and moderated inflammation in the animals’ skin.
As the Korean team wrote, the results demonstrate that “…ellagic acid works to prevent cell destruction and inflammation, thus preventing wrinkle formation and photo-aging [sunlight-induced skin damage] caused by UV destruction of collagen and the inflammatory response.”
Ellagic acid is a polyphenol-type antioxidant found in many fruits, vegetables and nuts—especially colorful ones like berries, greens, and cocoa.
Earlier studies suggest that, like ellagic acid, many polyphenol-type antioxidants protect against the free radicals and inflammation generated when sun strikes the skin.
But the benefits of eating foods rich in ellagic acid, such as raspberries, strawberries, and cranberries, extend well beyond cosmetic ones.
Population studies, backed by voluminous lab research, shows that antioxidant-rich diets probably help prevent heart disease, inflammatory diseases, diabetes, and some cancers.
Free radicals naturally occur in the body as a byproduct of food metabolism and other processes, but are also generated by external sources such as cigarette smoke, pesticides, and other environmental pollutants.
Whether applied to the skin—as cosmetic companies are increasingly doing—or eaten in the form of whole berries, polyphenol antioxidants may rank among the most effective ways to support the health of human skin.
- Bae Ji-Young, Young-Hee Kang, M.D., Jung-Suk Choi, Sang-Wook Kang, Dong Shoo Kim, and Jung Lye Kim. Ellagic Acid Prevents Ultraviolet Radiation-induced Chronic Skin Damage of Skin Cells in Hairless Mice. FASEB. 21 April 2009.
- Greul AK, Grundmann JU, Heinrich F, Pfitzner I, Bernhardt J, Ambach A, Biesalski HK, Gollnick H. Photoprotection of UV-irradiated human skin: an antioxidative combination of vitamins E and C, carotenoids, selenium and proanthocyanidins. Skin Pharmacol Appl Skin Physiol. 2002 Sep-Oct;15(5):307-15.
- Jimenez F, Mitts TF, Liu K, Wang Y, Hinek A. Ellagic and tannic acids protect newly synthesized elastic fibers from premature enzymatic degradation in dermal fibroblast cultures. J Invest Dermatol. 2006 Jun;126(6):1272-80.
- Kasai K, Yoshimura M, Koga T, Arii M, Kawasaki S. Effects of oral administration of ellagic acid-rich pomegranate extract on ultraviolet-induced pigmentation in the human skin. J Nutr Sci Vitaminol (Tokyo). 2006 Oct;52(5):383-8.
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- Katiyar SK, Perez A, Mukhtar H. Green tea polyphenol treatment to human skin prevents formation of ultraviolet light B-induced pyrimidine dimers in DNA. Clin Cancer Res. 2000 Oct;6(10):3864-9.
- Machlin, L.J., A. Bendich. Free radical Tissue Damage: Protective Role of Antioxidant Nutrients. The FASEB Journal, Vol 1, 441-445.
- Mireles-Rocha H, Galindo I, Huerta M, Trujillo-Hernández B, Elizalde A, Cortés-Franco R. UVB photoprotection with antioxidants: effects of oral therapy with d-alpha-tocopherol and ascorbic acid on the minimal erythema dose. Acta Derm Venereol. 2002;82(1):21-4.
- Moehrle M, Dietrich H, Patz CD, Häfner HM. Sun protection by red wine? J Dtsch Dermatol Ges. 2009 Jan;7(1):29-32, 29-33. Epub 2008 Jul 31. English, German.
- Palombo P, Fabrizi G, Ruocco V, Ruocco E, Fluhr J, Roberts R, Morganti P. Beneficial long-term effects of combined oral/topical antioxidant treatment with the carotenoids lutein and zeaxanthin on human skin: a double-blind, placebo-controlled study. Skin Pharmacol Physiol. 2007;20(4):199-210. Epub 2007 Apr 19.
- Stahl W, Sies H. Carotenoids and flavonoids contribute to nutritional protection against skin damage from sunlight. Mol Biotechnol. 2007 Sep;37(1):26-30. Review.