Dark Chocolate: A Valentine for Your Health
Many foods that nutrition scientists find are good for us can be difficult to love. Think of broccoli, which the first President Bush famously refused to eat. But then there’s chocolate, which study after study reports has health benefits to match its deliciousness. The only trouble with chocolate, of course, is that it’s also high in calories and fat.
What’s a sensible way to strike a balance between enjoying chocolate’s health (and taste) benefits and minimizing its downsides? With the chocolate-giving holiday of Valentine’s Day in mind, we posed that question to Jeffrey B. Blumberg, PhD, director of Tufts’ HNRCA Antioxidants Research Laboratory and a noted expert on the health effects of the antioxidant polyphenol compounds found in chocolate.
"The evidence that polyphenols—specifically the flavonoids and, especially, the flavanols—in chocolate have some health benefits continues to grow," says Blumberg. "The highest concentrations of these polyphenols are found in dark chocolate. Studies have particularly focused on cardiovascular endpoints like blood pressure and vascular reactivity. Indeed, enough data has now been generated from these studies that positive results have been demonstrated in several published systematic reviews and meta-analyses.
"However, the flavanols in chocolate are still inside the chocolate, an indulgent treat rich in calories from sugar and saturated fat (albeit much as the ‘neutral’ fatty acid, stearic acid, that does not increase LDL). So, while you may derive some health benefit from chocolate, a prudent recommendation
must be to do so (surprise!) in moderation."
JUST A BITE: What counts as "moderation" when it comes to chocolate? Blumberg points to an 18-week randomized clinical trial published in JAMA in 2007 that found just 6.3 grams of dark chocolate (with only 30 calories) daily had a beneficial effect on blood pressure in people with slightly elevated blood pressure (pre-hypertension and stage-one hypertension).
"Other studies support the amount of this ‘dose,’" Blumberg adds. "So, inclusion of small amounts of dark chocolate as part of a usual diet has no untoward effects and may promote heart health."
Don’t take that as license to gobble a couple of candy bars every day, however. Blumberg notes that 6.3 grams—0.2 ounces—is only about half of a single square of a typical 100-gram bar of dark chocolate. It’s about the size of a foil-wrapped bite-sized chocolate piece (but remember that you’ll get the most polyphenols in dark chocolate).
"Of course, there are other ways to incorporate cocoa flavanols in foods and beverages (think high-quality cocoa powder)," says Blumberg. “But most people want chocolate, especially on Feb. 14!"