The Journal of Nutrition published a study called Long-Term Ingestion of High Flavanol Cocoa Provides Photoprotection against UV-Induced Erythema and Improves Skin Condition in Women. Though by no means new–it was published in 2006–this is an important point of information in the world of (dark) chocolate lovers.
This study followed 24 women divided into two groups: low-flavanol cocoa and high-flavanol cocoa. Before anyone looses her head, there was control group: this was a paired means study (stats FTW) where various biological indicators were studied before and after consuming the cocoa beverages for 12 weeks. This means there was a nice baseline to study things against. If you read the study, you will find a controlled trial–one which actual conclusions can be drawn from (unlike observational studies).
After 12 weeks of consuming beverages with either 329 mg or 27 mg cocoa flavanols each morning, reseachers found that the group with high-flavanols was all-around better off and the other group nearly unaffected. After three months of the 329 mg flavanol cocoa drink, subjects were 25% more resistant to UV damage, had improved circulation (both under the skin and within it), suffered less water loss while having better moisturized skin, and saw skin become less scaly and rough.
These benefits are pretty impressive, given you can get the same dose of flavanols from about 100 g (3.5 oz) of deep, dark chocolate. So, smoother, better hydrated, less irritated skin–all with the sacrifice of eating 3.5 oz of chocolate per day! To those who say “Beauty is pain,” I say, “Chocolate!”