André Karwath/Creative Commons

For serious chocoholics (you know who you are), the best health-related news in the past decade had to be that dark chocolate is good for you. A recent Yale study concluded that eating dark chocolate can mean better cardiovascular health, with short-term improvements in blood pressure and arterial function.

Even better news is that milk chocolate may also have some health benefits.

So which one is the healthier snack? It depends, says Penny Kris-Etherton, distinguished professor of nutrition at Penn State. In general, dark chocolate has more health benefits. But more important is how the chocolate has been processed.

Explains Kris-Etherton, the most beneficial substance in chocolate is a type of antioxidant called polyphenols, which are found in the cacao bean, as well as in many fruits and vegetables, and in red wine and green tea. "There are many kinds of dark chocolates out there that contain polyphenolic compounds," she says, "but many milk chocolates contain them as well."

However, Kris-Etherton points out that "many" does not mean all. "There are some dark chocolates, usually inexpensive and manufactured using the Dutch process, that have lower levels of bioactive compounds in them," she says. Dutch-processed chocolate is treated with an alkalizing agent to modify its color and give it a milder flavor, but the process also destroys some of the antioxidants.

So how can you tell a healthy chocolate from a not-so-healthy chocolate? It isn't easy, Kris-Etherton admits. Consumers, she says, need to do a little homework before popping a tasty bite into their mouths.

""A few of the large chocolate manufacturers have started to label the flavanol content of some dark chocolates on the front of the package. You can also check the Web site or contact the company to find out if the chocolate contains bioactive compounds," she suggests. While that might seem like too much hassle to get the lowdown on your favorite candy bar, those who prefer milk chocolate could be in for a pleasant surprise.

"Milk chocolate is higher in saturated fats that raise blood cholesterol levels, but really good milk chocolates have some bioactives in them," Kris-Etherton says. "And if the candy bar has nuts, then you are deriving the benefits from a combination of foods. A milk chocolate bar with almonds or peanuts confers benefits due to both the chocolates and the nuts."

Unfortunately, chocolate is not going to be included as a necessary daily supplement any time soon. It still contains sugar and fat, and, thus, is a rich source of calories. To add that healthy chocolate to your diet (and not gain unhealthy extra pounds), it has to fit into your daily allotment of discretionary calories.

"In a 2000-calorie diet, you have 267 discretionary calories," Kris-Etherton notes: the equivalent of one candy bar. That's if you strictly toe the line on everything else. Most women, she adds, need fewer than 2000 calories a day—a sedentary woman may need only 1600, for example. On average, men require about 500 calories more. "There isn't a whole lot of room to play with," Kris-Etherton says.

Still, there are many portion-controlled chocolate products available in the marketplace (i.e. individually wrapped tasting squares) and ways to incorporate chocolate into other foods, she says, such as putting cocoa powder into a glass of skim milk. "You should have three servings of skim milk a day. So why not add chocolate to one of them?"

The key message, Kris-Etherton adds, is that people shouldn't think that chocolate is so healthy that they go out and overeat it. It still has negative nutrients (such as blood cholesterol-raising fat and sugar) and calories, although Kris-Etherton is hopeful that creative researchers will one day come up with a way to make chocolate more nutritious.

For now, she says, eat your dark chocolate or your milk chocolate in moderation. "Yes, there are health benefits, but incorporate it to your diet in a healthy way." Chocolate is a fun food and considered an extra in the diet, she stresses, and it should be treated that way.

Penny Kris-Etherton, Ph.D., is distinguished professor of nutritional sciences in the College of Health and Human Development; pmk3@psu.edu.