Cocoa is found to enhance the appearance and texture of skin and help protect it from sun damage… from the inside out
by Craig Weatherby
New findings from Germany give us another good reason to indulge in moderate amounts of dark chocolate and copious cups of unsweetened, non-Dutched cocoa: skin that is moister, smoother, better-looking, and more resistant to damage from the sun’s burning UV rays.
Researchers at Heinrich-Heine University in Dusseldorf divided 24 female volunteers with healthy, normal skin in two groups (Heinrich U 2006).
One group was instructed to enjoy a water-based cocoa drink high in antioxidant flavanols (326 milligrams per day), while the other group consumed a cocoa drink low in flavanols (27 milligrams per day).
To avoid possible outcome-confusing factors, the women did not change their diets, and took no dietary supplements during the 12-week trial. They were also asked to refrain from sunbathing and use of tanning beds.
The volunteers’ skin was exposed to 1.25 times the UV irradiation dose required to produce erythema (skin reddening) on the back and shoulder, at the outset, after six weeks, and at the end of the 12 week period.
The women who had been drinking the high-flavanol cocoa beverage enjoyed a 15 percent reduction of skin reddening in response to the UV radiation of after week 6, and reduction of 25 per cent after week 12, compared to their skin response at the beginning of the trial.
No such improvements in UV sensitivity were recorded in the women who drank the low-flavanol cocoa.
As the researchers wrote, “We showed here for the first time, to our knowledge, that dietary intervention with a cocoa beverage rich in flavanols decreased the sensitivity of human skin toward UV light, which was determined by the degree of erythema [skin reddening].”
In addition to the reduction in sensitivity to UV rays, the researchers also noted an increase in subcutaneous (under-skin) blood flow in the high flavanol group, as well as a noticeable improvement in skin texture. As they put it, “Evaluation of the skin surface showed a significant decrease of skin roughness and scaling in the high flavanol cocoa group…”
These beneficial changes likely resulted from the changes the researchers recorded after 12 weeks, compared to the measurements taken at the start of the study:
- 16 percent increase in skin density
- 12 per cent increase in skin thickness
- 28 percent boost in skin hydration
Again, as with skin reddening, no significant improvements were measured in the low-flavanol cocoa group.
These results were not very surprising, since the catechin-class polyphenols abundant in tea and cocoa absorb UV light and neutralize the destructive oxygen free radicals produced when UV rays strike the skin.
The German authors noted that the amounts of catechin-class polyphenols in the high-flavanol cocoa drink approximate those found in 100 grams (3.5 oz.) of extra-dark chocolate.
Note: Compared with the far more common “Dutched” (alkali-treated) cocoas, non-Dutched cocoa is much richer in flavanols, because the Dutching process destroys much of cocoa’s flavanols. (The cocoa in our Extra Dark Chocolate is non-Dutched.)
These results accord with those of animal studies in which tea flavanols reduced UV-induced skin reddening, but this is the first study to record a similar effect in humans. There may be something unique about the types and combinations of flavanols in cocoa versus tea, since a previous study in which people took supplemental green tea polyphenols did not show any UV-protective effects (Chow HH 2003).
We should note that the sugar in chocolate might reduce the benefits seen with cocoa, since it promotes inflammation, which in turn promotes micro-scarring in the skin that eventually manifests as wrinkles. However, the amount of flavanols in our extra dark chocolate is so high, in comparison to the amount of sugar in it that the benefits of the former are likely to far outweigh the downside of the latter.
- Heinrich U, Neukam K, Tronnier H, Sies H, Stahl W. Long-Term Ingestion of High Flavanol Cocoa Provides Photoprotection against UV-Induced Erythema and Improves Skin Condition in Women. J Nutr. 2006 Jun;136(6):1565-9.
- Sies H, Stahl W, Sevanian A. Nutritional, dietary and postprandial oxidative stress. J Nutr. 2005 May;135(5):969-72. Review.
- Chow HH, Cai Y, Hakim IA, Crowell JA, Shahi F, Brooks CA, Dorr RT, Hara Y, Alberts DS. Pharmacokinetics and safety of green tea polyphenols after multiple-dose administration of epigallocatechin gallate and polyphenon E in healthy individuals. Clin Cancer Res. 2003 Aug 15;9(9):3312-9.
- Katiyar SK. Skin photoprotection by green tea: antioxidant and immunomodulatory effects. Curr Drug Targets Immune Endocr Metabol Disord. 2003 Sep;3(3):234-42. Review.
- Katiyar SK, Bergamo BM, Vyalil PK, Elmets CA. Green tea polyphenols: DNA photodamage and photoimmunology. J Photochem Photobiol B. 2001 Dec 31;65(2-3):109-14. Review.
- Katiyar SK, Elmets CA. Green tea polyphenolic antioxidants and skin photoprotection (Review). Int J Oncol. 2001 Jun;18(6):1307-13. Review