Chocolate and Heart Health

January 21, 2012

Jessica, Registered Dietitian

This blog is for all of the chocolate-lovers out there, me included!  When you enjoy a certain food, don’t you look for validation that it is good for your health . . . or at least not bad? Well, the researchers are helping us out lately when it comes to chocolate. Since December, two separate university-published health newsletters that I subscribe to have featured recent studies that provide the most compelling evidence yet that chocolate is good for your heart.

A Harvard University study published in the European Journal of Clinical Nutrition reviewed 10 clinical studies conducted over the last 10 years with a total of 320 participants. The studies looked at the effect of consuming cocoa products for 2 to 12 weeks. Overall, consumption of dark chocolate was associated with a modest, statistically significant reduction in total cholesterol and LDL (“bad”) cholesterol (6.23 mg/dL reduction in total cholesterol and 5.9 mg/dL reduction in LDL). Other studies have reported blood-pressure-lowering effects in people with hypertension and pre-hypertension and even reduced risk of heart disease.

So what is it about chocolate, especially dark chocolate, that confers heart-health benefits? Cocoa contains plant compounds called flavonoids, which have anti-inflammatory and antioxidant properties. Flavonoids are also believed to stop cholesterol from being absorbed and reduce LDL oxidation (preventing plaque buildup in your arteries). This combination of effects leads to a healthier heart.

Now for the less-positive news (you knew it was coming for something as delicious as chocolate!) Many of the studies to date are observational, which means cause and effect cannot be established. There may be something else about dark chocolate-eaters that make them a more heart healthy group (maybe they love fiber and whole grains too). It is also hard to determine how much chocolate is necessary for the beneficial effects. Chocolate is high in calories and fat, so going overboard can lead to weight gain and other health implications. What is the right amount where benefits outweigh the risks?

If you do want to try to maximize the health benefits of chocolate, here are some tips:

  • Dark chocolate seems to have a higher flavonoid content than milk chocolate, so choose the highest cacao percent you enjoy. Milk chocolate can have twice as much sugar as dark chocolate too.
  • Cocoa powder is even higher in flavonoids than dark chocolate! “Dutch” processing destroys these beneficial compounds, so look for unsweetened natural cocoa powder for baking and cooking.
  • Chocolate is high in calories and fat, so it should still be considered a treat. Fruits and vegetables contain flavonoids and other healthy plant compounds for a fraction of the calories, so they should still be your main source of heart-healthy nutrients.

University of California, Berkeley Wellness Newsletter, Feb. 2012, Vol. 28, Issue 5
Tufts University Health & Nutrition Letter, Dec. 2011, Vol. 29, Number 10