Research studies conducted over the last decade have associated cocoa and dark chocolate consumption with heart health benefits. These benefits come from cocoa derived from the cacao plant, which is rich in flavonoids (cocoa flavanols to be exact). Flavonoids are antioxidants also found in berries, grapes, tea and apples. As a whole, antioxidants prevent cellular damage and inflammation – two major mechanisms involved in the development of heart disease.
So what does the research say?
A study published in the American Journal of Clinical Nutrition found that high-flavanol dark chocolate reduced bad cholesterol (LDL) oxidation and increased good cholesterol (HDL) levels. LDL oxidation promotes the development of plaque and hardening of the coronary arteries, thus lessening oxidation could help to prevent heart disease.1
Harvard researchers found that flavanol-rich cocoa activated nitric-oxide production, which causes blood vessels to relax and expand, resulting in improved blood flow. Better coronary vasodilation could potentially lower the risk of a cardiovascular event.2
In a double-blind randomized study, flavonoid-rich dark chocolate (containing 70 percent cocoa) reduced serum oxidative stress and decreased platelet activity (clumping) in heart transplant recipients. This favorable impact on vascular and platelet function is relevant because vascular dysfunction and platelet activation (adhesion upon damaged cell walls) are the basis of atherothrombosis (blood clotting) and coronary artery disease.3
How can you reap chocolate’s potential benefits?
Not all cocoa products and/or chocolates are created equal. Milk chocolate, for example, is not rich in flavanols and contains only 10 to 20 percent cocoa solids. White chocolate contains none at all. In addition, some cocoa products and chocolates are processed with alkali, a substance that can destroy flavanols.
Follow these tips for heart healthy chocolate consumption:
♥ Avoid cocoa products processed with alkali (Dutched) as seen in the ingredient list
♥ Choose dark chocolate with at least 70 percent cocoa
♥ Enjoy 100 percent unsweetened non-Dutched cocoa (great for hot chocolate!)
Also, remember that chocolate is not a health food, as it is high in calories, fat and added sugar. You can make room for dark chocolate by cutting extra calories elsewhere in your diet. Additionally, stick to small amounts (e.g. 1 ounce) and don’t eat chocolate in place of plant-based whole foods such as vegetables and fruits.
About: Cheryl Williams is a registered dietitian specializing in the nutritional management of a variety of chronic conditions including cardiovascular disease, diabetes and obesity. In her current position at the Emory Heart & Vascular Center, Cheryl provides nutrition therapy, wellness coaching, monthly nutrition seminars and healthy cooking demonstrations.
1 Chocolate procyanidins decrease the leukotriene-prostacyclin ratio in humans and human aortic endothelial cells1 Am J Clin Nutr 2001;73:36–40.
2 Flavanol-rich cocoa induces nitric-oxide-dependent vasodilation in healthy humans. J Hypertens. 2003 Dec;21(12):2281-6.
3 Dark Chocolate Improves Coronary Vasomotion and Reduces Platelet Reactivity. (Circulation. 2007; 2007 116:2376-2382).