Health Benefits of Chocolate
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Tasting Notes
I'm close to posting the following on my healthy lifestyle blog (Advanced Mediterranean Diet Blog), and wondered if you guys had any comments.__________________________________________________________________________________________________Theobroma cacao, the cocoa tree, has been cultivated in Central and South America for over 3000 years. Cocoa is derived from the tree's seed, also known as the cocoa bean.Chocolate is a product of the processed cocoa bean. Dark chocolate has at least 65% cocoa content, and has much more of the potentially healthy chemicals from the cocoa bean, as compared with milk chocolate. White chocolate isn't really chocolate.It's been a little over 10 years since we first read in a medical journal about cocoa and chocolate as potential sources of antioxidants for health. What have we learned since then?Phytochemicals are chemicals produced by plants, and there are hundreds of thousands of them. Polyphenols are a subset of phytochemicals. Flavonoids, with strong antioxidant properties, are a subset of polyphenols. And a subset of flavonoids, called flavonols, have particularly potent biological effects in humans. Prominent flavonols in dark chocolate are flavan-3-ol, catechin, and epicatechin. Also metabolically active are proanthocyanidins, which are polymeric condensation products of flavan-3-ol.Are you bored yet? Have I convinced you of my authority on the subject? Say yes, or I'll keep going! [Please say yes: I'm boring myself!]Note that some chocolate manufacturers process the cocoa beans to remove some of the polyphenols, to reduce bitterness or pungency.Other rich sources of flavonols are wine, tea, and various fruits and berries.How could dark chocolate, especially its flavonoids, be healthful?* Flavonoids are antioxidants that protect from injury caused by free radicals* Enhanced nitric oxide production, leading to relaxation of arteries (vasodilation), leading to reduced blood pressure: up to 6 mmHg systolic and 3 mmHg diastolic* Elevation of HDL cholesterol, with no effect on total and LDL cholesterol* Inhibition of platelet aggregation and activation, leading to fewer blood clots that cause heart attacks and strokes* Decreased inflammation* Reduction of C-reactive protein, a marker of inflammation* Decreased neutrophil (white blood cell) activation. White blood cells play a role in inflammation* Decreased LDL cholesterol oxidation, leading to fewer atherosclerotic complications* Improved function of the cells that line blood vessels (endothelium)* Possible enhanced insulin sensitivity* May act as anti-carcinogens and neuro-protective agents* May act as an antidepressantBottom line? Dark chocolate, especially because of flavonoids, may well be protective against cardiovascular disease such as heart attacks and strokes.[Did you notice I'm waffling . . . may be protective.]What's in dark chocolate other than flavonoids?A 40 gram serving of fine dark chocolate has:* Calories: 200* Calories from fat: 150* Fiber: 4.5 grams (a good source of fiber on a "per calorie" basis)* Sugar: 11 grams* Saturated fats: 10 grams"But aren't saturated fats bad for me?"The fats in dark chocolate are 1/3 oleic (healthy monounsaturated, as in olive oil), 1/3 stearic (saturated, but no effect on cholesterol levels, unlike some other saturated fats), and 1/3 palmitic (saturated, and could increase cholesterol levels and heart risk). So it's sort of a wash.[I'm not getting into the diet-heart hypothesis now. Don't bait me.]What's the healthy "dose" of dark chocolate?No one is sure. It's certainly no more than 100 grams (3.5 ounces) a day, and the optimal dose may be as low as 20 grams every three days. If you eat too much, it will make you fat. 100 grams is 500 calories; that's probably way too much. Even if you start eating 20 grams - 100 calories - every three days, you will gain weight unless you give up some other food or exercise a little more."Parker, why are you waffling?"Because no one has ever done a study to see if adding dark chocolate actually reduces death rates or sickness from specific diseases in humans. I think it probably does, but who knows for sure? Nobody. What we need is a randomized, controlled trial of dark chocolate as a supplement in 10,000 middle-aged adults followed over the course of 10 years. I'd sign up for that in a heartbeat. Just don't give me the placebo.Steve Parker, M.D.--------------References:Erdman, J.W., et al. Effects of cocoa flavanols on risk factors for cardiovascular disease. Asian Pacific Journal of Clinical Nutrition, 17 supplement 1 (2008): 284-287.Farouque, H.M, et al. Acute and chronic effects of flavanol-rich cocoa on vascular function in subjects with coronary artery disease: a randomized double-blind placebo-controlled study. Clinical Science, 111 (2006): 71-80.Heptinstall, S., et al. Cocoa flavanols and platelet and leukocyte function: recent in vitro and ex vivo studies in healthy adults. Journal of Cardiovascular Pharmacology, 47 supplement 2 (2006): S197-205.Keen, C.L., et al. Cocoa antioxidants and cardiovascular health. American Journal of Clinical Nutrition, 81 supplement 1 (2005): 298S-303S.Mehrinfar, R. and Frishman, W.H. Flavanol-rich cocoa: a cardioprotective nutraceutical. Cardiology Reviews, 16 (2008): 109-115.Engler, M.B, and Engler, M.M. The emerging role of flavonoid-rich cocoa and chocolate in cardiovascular health and disease. Nutrition Reviews, 64 (2006): 109-118.Lippi, G. et al. Dark chocolate: consumption for pleasure or therapy? Journal of Thrombosis and Thrombolysis, September 23, 2008 (Epub ahead of print).Hooper, L, et al. Flavonoids, flavonoid-rich foods, and cardiovascular risk: a meta-analysis of randomized controlled trials. American Journal of Clinical Nutrition, 88 (2008): 38-50.Cooper, K.A., et al. Cocoa and health: a decade of research. British Journal of Nutrition, 99 (2007): 1-11. Epub August 1, 2007.Aron, P.M., and Kennedy, J.A. Flavon-3-ols: nature, occurrence and biological activity. Molecular Nutrition and Food Research, 52 (2008): 79-104.Buijsse, B, et al. Cocoa intake, blood pressure, and cardiovascular mortality [in men]: the Zutphen Elderly Study. Archives of Internal Medicine, 166 (2006): 411-417.Ding, E.L., et al. Chocolate and prevention of cardiovascular disease: a systematic review. Nutrition and Metabolism, 3 (2006): 2.
There is no evidence that cacao was being cultivated in South America 3000 years ago. There is evidence of the use of cocoa beans to make beverages in Mesoamerica at least as far back as 1900BC and because cacao is not native to Mesoamerica it is assumed that it was cultivated. (In South America, the pulp was used to make alcoholic beverages and there is evidence that the seeds were consumed.)-) There is no legal definition for "dark" chocolate. There is a minimum cacao content for "sweet" chocolate (which covers both semi-sweet and bittersweet). Conventionally, dark chocolate is any chocolate that does not contain any dairy products. However, this definition is not entirely useful as the FDA standards of identity for even chocolate liquor allow manufacturers to include dairy fats in their recipes. A workable definition of dark chocolate is a chocolate that does not contain any dairy ingredients and you have to read the ingredients label to figure it out because there is nothing in the standards of identity or labeling laws that covers the use of the word "dark" when it is applied to chocolate. Ironically, there is a standard of identity for white chocolate, so legally (anyway, in the US) white chocolate is really chocolate.-) If your readership understands what is meant by "... which are polymeric condensation products ..." then it is an unusual group of readers. If not, you might want to consider either defining what this means or changing the phrase.-) I don't know of any manufacturers who say, "Let's remove the polyphenols in the chocolate to make it less bitter." Instead, they use various practices to remove bitterness, the result of which processes is the reduction of the level of polyphenols (and other chemicals).-) There is no absolute measurement for the caloric content of 40 grams of chocolate or the percentage of those calories that come from fat, and the inclusion of the word "fine" is a little confusing. Calorie content is not dependent on processing, it's dependent on the makeup of the chocolate. 40 grams of a "fine" 100% cocoa content bar is going to have a different fat/calorie ratio than a 72% bar. In fact, there will be variations in 72% bars depending on the total fat content.-) You are right, there is no RDA for chocolate and there probably never will be. If there is a bit of advice I would offer it is that chocolate (and cocoa products) made using "natural" (non-alkalized or non Dutch processed) cocoa tend to be much higher in antioxidants than chocolate products made with alkalized cocoa. Although cocoa butter tends to be neutral in people with "normal" cholesterol metabolism, choosing cocoa products that are also low-fat (such as cocoa powder) is an alternative to consider. Thus, if one is interested in maximizing the potential wellness benefits from cacao, finding ways to incorporate low-fat, non-alkalized cocoa powder into the diet is one way to go. I am satisfied based on my reading that cocoa butter is in part responsible for the regulation of the ratios of LDL/HDL/triglycerides so some cocoa butter in the diet is a good thing. How much? Who knows? The health aspects of eating chocolate are a bonus, not a reason, to eat chocolate.-) One of the reasons that the double-blind study you're suggesting might not ever happen is that whoever organizes it will need to completely characterize the chemical makeup of the chocolate(s) being used for the study - which hasn't been done until now. Then, someone would need to find correlations between the chemical makeup and the results. So, it probably shouldn't be a placebo that gets used, but several chocolates with precisely known, but different chemical makeups in an attempt to understand (if possible) which aspects of chocolate's chemistry contribute to which benefits.
