Chocolate consumption can reduce cardiac risk by a third, according to a very recent pronouncement based on meta-analyses of previous works. Scientists report that chocolate could be a viable factor in the reduction of heart disease and metabolic syndrome by virtue of its polyphenol content, keeping company with fruits and vegetables, extra virgin olive oil, wine and teas. The scientists who offered this report were careful to note that none of the seven trials that were examined had followed all the hallmarks of the scientific protocol, including control and randomization, meaning that a control group / trial group selection was not done to eliminate bias in treatment. On the other hand, empirical results were used to support the hypotheses.
Although he commented that additional, randomized and controlled studies are needed to ascertain these results, lead scientist, Oscar Franco, working at England’s Cambridge University, said that, “…levels of chocolate consumption seem to be associated with a substantial reduction in the risk of cardiometabolic disorders.” After looking carefully at more than one hundred thousand study participants and examining their risks for CVD, diabetes, stroke and metabolic syndrome, Franco and his group noted that, “The highest levels of chocolate consumption were associated with a 37% reduction in cardiovascular disease…and a 29% reduction in stroke compared with the lowest levels.” Based on these observations, levels of chocolate consumption seem to be associated with a substantial reduction in the risk of cardiometabolic disorders.
This is not the first study to compliment chocolate for its inherent character, but it does make the loudest presentation. It’s the polyphenols in cocoa that are the heroes, a class of compounds that includes the bioflavonoids (of which there are a few thousand), lignins, and tannins. The flavonoids in chocolate comprise the highest concentration among commonly consumed foods—more than ten percent of the weight of cocoa powder. Among them, catechin and epicatechin, two of the procyanidin flavonoids, are among the most abundant, and are also found in tea. These flavonoids oppose free radical injury because of their antioxidant effect, but also have been found to lower total cholesterol, to reduce blood pressure, to inhibit sticky platelets, and to improve blood flow to vital organs. (Pryde. 2011) One anti-hypertensive attribute of cocoa is the activation of nitric oxide, a gas that occurs in the body naturally, which is released from vascular epithelial cells to inhibit muscular contraction and thereby induce relaxation of blood vessels. (Corti. 2009) (Buijsse. 2010)
Flavonoids exist in all plant foods, where they shield a plant from environmental insults and offer the means to repair damage. When we consume these plants, the benefit passes to us, including the capability to resist oxidative damage from things like cigarette smoke, vehicular and factory discharge, and poor dietary choices. Some chocolate flavonoids may be lost to processing, but manufacturers are looking to control that.
Research at Harvard Medical School looked more closely at subclinical coronary disease and diet, finding an inverse relationship between calcified plaque and chocolate consumption. (Djousse. 2011) Those who consumed dark chocolate—never milk chocolate—once or twice a week (about an ounce at a time) demonstrated a greater positive result than those who consumed it less than three times a month. The inclusion of chocolate in so stellar a group as green tea and soy as contributors to heart health is no small feat, considering that chocolate is more of a snack food than part of a meal. That it was seen to lower diastolic blood pressure as well as systolic is a feather in its cap. (Hooper. 2008)
We have to keep in mind that chocolate is relatively high in lipids, which means it’s high in calories. The saturated stearic acid constitutes one-third of the fats in cocoa butter, but has zero influence on cholesterolemic response. Another one-third fat fraction in cocoa is oleic acid, a heart-healthy monounsaturated fat, followed by the last third, palmitic acid, which is saturated but self-limiting, even though it is the first fatty acid produced during lipogenesis (the synthesis of fatty acids by the body). In the presence of linoleic acid (an omega-6) at 4.5% of calories (~90 calories), palmitic acid has no effect on cholesterol levels. (French. 2002) So, the calories in chocolate can be healthy. But we must be reminded not to have too much of a good thing.
Adriana Buitrago-Lopez, Jean Sanderson, Laura Johnson, Samantha Warnakula, Angela Wood, Emanuele Di Angelantonio, Oscar H Franco Chocolate consumption and cardiometabolic disorders: systematic review and meta-analysis BMJ 2011; 343:d4488 doi: 10.1136/bmj.d4488 (Published 29 August 2011)
Moira McAllister Pryde and William Bernard Kannel Efficacy of Dietary Behavior Modification for Preserving Cardiovascular Health and Longevity Cardiol Res Pract. 2011; 2011: 820457.
Corti R, Flammer AJ, Hollenberg NK, Lüscher TF Cocoa and cardiovascular health. Circulation. 2009 Mar 17;119(10):1433-41.
Buijsse B, Weikert C, Drogan D, Bergmann M, Boeing H. Chocolate consumption in relation to blood pressure and risk of cardiovascular disease in German adults. Eur Heart J. 2010 Jul;31(13):1616-23.
Djoussé L, Hopkins PN, North KE, Pankow JS, Arnett DK, Ellison RC. Chocolate consumption is inversely associated with prevalent coronary heart disease: the National Heart, Lung, and Blood Institute Family Heart Study. Clin Nutr. 2011 Apr;30(2):182-7.
Djoussé L, Hopkins PN, Arnett DK, Pankow JS, Borecki I, North KE, Curtis Ellison R. Chocolate consumption is inversely associated with calcified atherosclerotic plaque in the coronary arteries: the NHLBI Family Heart Study. Clin Nutr. 2011 Feb;30(1):38-43.
Hooper L, Kroon PA, Rimm EB, Cohn JS, Harvey I, Le Cornu KA, Ryder JJ, Hall WL, Cassidy A. Flavonoids, flavonoid-rich foods, and cardiovascular risk: a meta-analysis of randomized controlled trials. Am J Clin Nutr. 2008 Jul;88(1):38-50.
French MA, Sundram K, Clandinin MT. Cholesterolaemic effect of palmitic acid in relation to other dietary fatty acids. Asia Pac J Clin Nutr. 2002;11 Suppl 7:S401-7.
Steinberg FM, Bearden MM, Keen CL. Cocoa and chocolate flavonoids: implications for cardiovascular health. J Am Diet Assoc. 2003 Feb;103(2):215-23.
*These statements have not been evaluated by the FDA. These products are not intended to treat, diagnose, cure, or prevent any disease.