Is Dark Chocolate Healthier Than Milk Chocolate?

This article is a compilation of two pieces that originally appeared in the Tufts Health & Nutrition Letter, published each month by the Friedman School of Nutrition Science and Policy. Subscribe here to get more expert guidance on healthy cooking, eating, and living.

What’s the difference between dark chocolate and milk chocolate, and is dark chocolate really healthier?

One of the main differences: “Dark chocolate does not contain milk or milk solids, and dark chocolate is typically lower in added sugars,” said registered dietitian Camille Finn, N18, who was a dietetic intern at Frances Stern Nutrition Center at Tufts Medical Center. 

So the answer is a tentative yes–especially because, as Finn added, dark chocolate has a higher percentage of cacao, or cocoa solids, than milk chocolate. “As the cacao percentage increases, the chocolate becomes stronger in flavor and contains more compounds from the cocoa beans that may be beneficial,” Finn said.

Jeffrey Blumberg, a Professor Emeritus at the Friedman School of Nutrition Science and Policy at Tufts University, has found that one of these compounds in particular–a type of antioxidant called flavenoids–may contribute to the health of our blood vessels and help reduce blood pressure.

“Milk chocolate does contain flavonoids (about 75 milligrams per 100 grams)—more than found in a comparable amount of red wine or tea, though less than dark chocolate (170 milligrams per 100 grams,” said Blumberg, who did research on the topic while working in the Antioxidants Research Laboratory at the Human Nutrition Research Center on Aging at Tufts. 

And it’s not just their higher concentration that makes these antioxidants more effective in dark chocolate. “Some research suggests that milk may interfere with the absorption of flavanols from chocolate,” Finn said. (Flavonols are a specific type of flavenoid.) “Thus, dark chocolate can be a better source of flavanols since it does not contain milk.”

However, she pointed out that while dark chocolate is defined in Europe as containing at least 35 percent cacao, there is no specific minimum cacao percentage for dark chocolate in the United States, meaning there is no guarantee that dark chocolate in this country will contain significantly more cocoa solids than its milky counterpart.

Blumberg said the same, noting, “Flavonoids in milk versus dark chocolate vary markedly by brand." Further, Blumberg pointed out that the FDA does not require chocolate producers to list the flavonoid content, and recent lawsuits have led some to actually delete such data. “There is no reference standard (RDA or DV) for flavonoids, so no product can claim to be a ‘good’ or ‘rich’ source of them,” he said.

To maximize the flavonoids in your chocolate, Blumberg recommended choosing dark, bittersweet, or baking chocolate, rather than milk chocolate, which is alkalinized (“dutched”) to make it smoother and less bitter, but which also decreases its natural flavonoid content.

It’s also worth keeping in mind that chocolate contains calories. So if you love chocolate, it’s probably fine to eat some even every day—but choose chocolate instead of other caloric snacks or treats. Substitute that chocolate bar for chips, bakery goods, or other indulgences high in calories, sugar and saturated fat, rather than adding it to your daily diet.

“Although high in calories, small amounts of dark chocolate can be included as part of a healthful diet,” Finn said.