The skin has an inherent sun-protection that largely depends on how much melanin the skin contains. The more melanin, that is, the darker the skin, the more sun the skin can tolerate. But apart from that, the strength of the skin's antioxidant defense also plays an important role. When the sun's UV-rays hit the skin, free radicals are formed that cause damage to the skin cells' DNA, proteins and membrane lipids, resulting in an inflammatory response that makes the skin red. This is what we call sunburn. If the skin has a stronger antioxidant defense that neutralizes the free radicals, the skin can support a higher dose of sunshine before it starts to turn red. Antioxidants in lotions might help out a bit but not at the deeper layers of the skin since they are not taken up by the skin. On the other hand, dietary intake of food with a high content of antioxidants increase the antioxidant defense in the whole body, including the skin. This has caused quite an interest in certain foods rich in various types of antioxidants such as beta-carotene, lycopene, vitamin C, vitamin E, omega-3 fatty acids and various types of polyphenols. We are talking about carrots, sweet potatoes, tomatoes, watermelons, strawberries, kiwis, oranges, almonds, sunflower seeds, oily fish, green tea and red wine, chocolate and various berries.....the list can be made very long. The question is what actually does have an effect without you having to eat kilos of a certain food day in, day out. In this article, we take a closer look at what actually has been shown scientifically for a real favorite, namely chocolate.
Cocoa Beans Are a Superfood
Fresh cocoa (or cacao) beans are extremely rich in the flavanols catechin and epicathecin [1,2]. Flavanols are a type of polyphenols that are also abundant in blueberries, cranberries, grapes, apples, tea and red wine. Catechin and epicathecin are strong antioxidants and anti-inflammatory agents. This has spurred an interest in medical science for their positive effects on health and their ability to improve various diseases. The fact is that fresh cocoa beans have several times higher antioxidant capacity than the famous red wine and green tea.
Can Eating Chocolate Protect Against the Sun?
So how is it with the skin's inherent sunscreen? Can eating chocolate make us less sensitive to the sun's UV-rays? A number of scientific studies have looked at the effects of long periods of daily consumption of chocolate and the skin's sensitivity to UV-light, measured as the lowest dose that causes skin redness. All of the studies include two types of chocolate, so-called high-flavanol chocolate and normal dark chocolate of the type 70%. High-flavonol chocolate is made with an especially mild production process that uses lower temperatures making the flavanol content about 10-20 times higher than normal chocolate. The majority of the flavanols is unfortunately lost during the process used to obtain the chocolate we normally find in the stores [3]. Above all, it is the roasting of the cocoa beans that is a great problem. The amount of chocolate consumed in the studies is reasonable and in line with what you could eat every day. The study participants consumed 15-20 g of chocolate or alternatively 100 ml of a cocoa drink per day for 2 weeks up to 3 months [4,5]. And the answer is a clear yes, chocolate does protect against UV-light. In 2-3 months time, you can achieve a doubling of the dose of UV-light that the skin can sustain without getting red. But, and this a huge but, only with high-flavanol chocolate that gives a daily dose of 300-600 milligram flavonols. The same amount of normal dark chocolate only contains about 30 milligram flavanols and resulted in no measurable effect on the skin's sensitivity against UV-light. In addition, high-flavanol chocolate had other positive effects on the skin in the studies such as increased micro-circulation, increased moisture content, reduced transepidermal water loss (TEWL), increased elasticity and reduced skin roughness [4,6,7]. In addition to the effect on skin-sensitivity to UV-light, there are other promising scientific research going on concerning the ability of chocolate to lower blood pressure, improve cardiovascular health, improve insulin sensitivity and lower the blood sugar, which has positive effects on both cardiovascular disease and diabetes [8,9].
Labeling With Flavanol Content Wanted
There are many steps in the process of turning fresh cocoa beans into cocoa where the amount of flavanols are negatively affected and roasting is just one of them [3]. Fermenting, drying, roasting and various tempering steps all require heat. In addition, the amount of flavanols varies hugely between different types of cocoa beans and their geographical origin. [2,10]. Raw chocolate is sold with the argument that it is processed with less heat than normal chocolate. Usually, it means that the beans are not roasted, but not that they are unprocessed. Still, you can assume that raw chocolate contains higher amounts of flavanols than normal dark chocolate. Unfortunately, you never see any values for flavanol content on the packaging. It is therefore difficult to know how much more flavanols raw chocolate contains and if it is comparable to the levels in the high-flavanol chocolate used in the scientific studies.
To really consider chocolate as a superfood with positive effects on cardiovascular health, blood sugar, increased skin-tolerance against the sun, better microcirculation in the skin, etc. we would like to see chocolate with specified flavanol content, just as many products are labeled with how much vitamin and trace elements they contain. Then you could really stop thinking of chocolate as unhealthy candy and instead start to look at it as a daily health supplement. What a dream!
References
- Crozier, S.J. et al., Cacao seeds are a "Super Fruit": A comparative analysis of various fruit powders and products. Chem Cent J, 2011. 5: 1-5.
- Andujar, I. et al., Cocoa polyphenols and their potential benefits for human health. Oxid Med Cell Longev, 2012. 2012: 906252.
- Di Mattia, C.D. et al., From Cocoa to Chocolate: The Impact of Processing on In Vitro Antioxidant Activity and the Effects of Chocolate on Antioxidant Markers In Vivo. Front Immunol, 2017. 8: 1207.
- Heinrich, U. et al., Long-term ingestion of high flavanol cocoa provides photoprotection against UV-induced erythema and improves skin condition in women. J Nutr, 2006. 136(6): 1565-9.
- Williams, S. et al., Eating chocolate can significantly protect the skin from UV light. J Cosmet Dermatol, 2009. 8(3): 169-73.
- Neukam, K. et al., Consumption of flavanol-rich cocoa acutely increases microcirculation in human skin. Eur J Nutr, 2007. 46(1): 53-6.
- Mogollon, J.A. et al., Chocolate flavanols and skin photoprotection: a parallel, double-blind, randomized clinical trial. Nutr J, 2014. 13: 66.
- Gammone, M.A. et al., Impact of chocolate on the cardiovascular health. Front Biosci (Landmark Ed), 2018. 23: 852-864.
- Strat, K.M. et al., Mechanisms by which cocoa flavanols improve metabolic syndrome and related disorders. J Nutr Biochem, 2016. 35: 1-21.
- Zyzelewicz, D. et al., The effect on bioactive components and characteristics of chocolate by functionalization with raw cocoa beans. Food Res Int, 2018. 113: 234-244.