If your Valentine's Day plans involve picking out a box of chocolates for someone special, your best choice for your loved one’s heart might be dark chocolate. The cacao bean contains more than 400 chemicals, and many of them can affect human health. One group of chemicals, the flavonoids, are responsible for many of the protective actions of dark chocolate, reports the February issue of Harvard Men's Health Watch.
Flavonoids are present in many healthful foods, like apples and cherries, but dark chocolate is the richest source. So it’s no surprise that chocolate has attracted the interest of scientists from around the world, giving the research an international flavor. Most studies have concentrated on cardiovascular health; here are some representative findings:
Antioxidant activity. Among other beneficial actions, flavonoids protect LDL cholesterol from oxidation, which puts the “bad” into “bad cholesterol.” Dark chocolate reduces LDL oxidation while actually increasing levels of HDL (good) cholesterol.
Endothelial function. The endothelium, the thin inner layer of arteries, is responsible for producing nitric oxide, a chemical that widens blood vessels and keeps their linings smooth. European studies have shown that dark chocolate improves endothelial function in healthy people, that flavonoid-rich cocoa can reverse the endothelial dysfunction produced by smoking, and that dark chocolate may improve coronary artery function in heart transplant patients.
Blood pressure. Studies from Italy, Argentina, Germany, and the United States show that dark chocolate can lower blood pressure, though the effect is modest. The benefit wears off within a few days of stopping “treatment” with a daily “dose” of dark chocolate.
Blood clotting. Most heart attacks and many strokes are caused by blood clots that form in critical arteries. Researchers in Switzerland and the United States found that dark chocolate reduces platelet activation, a step in clot formation.
More research is needed to confirm these preliminary findings and to learn if they translate into sustained health benefits. And remember that there is a dark side to dark chocolate: calories.