Dark Chocolate: Heart-Healthy or Harmful?

Derived from the pods of the cacao tree, whose botanical name, Theobroma, means “food of the gods,” dark chocolate is rich in flavanols and polyphenols, antioxidant compounds also found in tea, wine, fruits and vegetables. Recent research suggests that dark chocolate has the following benefits for heart health:

• Lower risk for coronary artery disease (CAD). In the latest study of chocolate’s effects on heart health, researchers from the Cleveland Clinic and other centers analyzed findings from six studies that included 336,289 people. Published in European Journal of Preventive Cardiology, the analysis linked eating chocolate more than once a week to an 8 percent reduction in risk for developing CAD (plaque in the arteries that can lead to a heart attack).
• Chocolate may help prevent irregular heartbeats. In a recent Harvard study of more than 55,000 people, eating moderate amounts of chocolate lowered risk for atrial fibrillation (AF), a common and dangerous type of heart arrhythmia that elevates risk for stroke, heart failure, cognitive decline, dementia and early death.
• Reduced risk for heart attacks and strokes. In a study of nearly 20,000 people ages 35 to 65, those who ate the most chocolate had a 39 percent lower risk for heart attack and stroke. The researchers also linked chocolate consumption to lower blood pressure, a factor that may explain its protective properties, since high blood pressure is the leading risk for stroke and a major contributor to heart attacks.
• Protection against high blood pressure during pregnancy. A Yale study of 2,291 pregnant women found that those who ate more than five servings of chocolate a week reduced their risk of developing pre-eclampsia, pregnancy-induced high blood pressure, by up to 40 percent, compared to women who ate less than one serving a week. Pre-eclampsia is a potentially life-threatening condition that affects about 5% of American moms-to-be and raises their risk for heart disease later in life.
• Healthier levels of cholesterol and other markers of heart health. Products rich in cacao flavanols (such as dark chocolate or cocoa) may reduce inflammation, triglycerides and insulin resistance (the root cause of almost all cases of type 2 diabetes, as well as 70 percent of heart attacks), according to an analysis of clinical trials that included more than 1,100 people. The researchers also linked these foods to healthier levels of HDL (good) and LDL (bad) cholesterol.