Health Benefits of Dark Chocolate

Medically Reviewed by Jabeen Begum, MD on August 18, 2023
5 min read

Dark chocolate is any chocolate that contains at least 50% cocoa solids, cocoa butter, and sugar. Unlike milk chocolate, dark chocolate isn't made with milk, though it could have trace amounts from cross-contamination during manufacturing. Lower-quality dark chocolate also could have oils, butter fats, and artificial flavors. 

Humans have been consuming chocolate since the Mayans first drank it around 1500 B.C. Chocolate is still a popular treat today, and now we have even more reasons to crave it, especially dark chocolate. 

Does dark chocolate have caffeine?

The more cocoa solids, the more caffeine, in fact. A 3.5-ounce serving of dark chocolate with 70%-85% cacao has 80 milligrams of caffeine. In comparison, an 8-ounce cup of brewed coffee contains about 95 milligrams and a 12-ounce can of caffeinated soda has between 40 and 55 milligrams. If you’re watching your caffeine intake, keep an eye on how much is in your dark chocolate, too.

Is dark chocolate vegan?

Check the label. Cocoa is vegan in its natural form. But some brands of dark chocolates pick up small amounts of dairy during processing. Other added ingredients like whey, casein, and lactose are dairy products too. 

Is dark chocolate good for you?

Dark chocolate does have some components that offer health benefits. But it's fairly high in calories, fat, and added sugar. As with many foods, it's best if you eat it in moderation. It has less sugar than milk chocolate, so it's the better choice of the two. 

The cocoa used to make dark chocolate is rich in flavanols, which are chemicals found in plants like the cacao tree (where the cocoa bean grows). The unique flavan-3-ols in cacao beans are what gives pure cocoa a bitter taste.

Because cocoa's flavanols have antioxidant and anti-inflammatory properties, it might help to:

Protect your heart

Separate studies have shown that dark chocolate may guard against heart and blood vessel (cardiovascular) disease. Dark chocolate seems to have anti-inflammatory effects as well as properties that help prevent blood clots and lower blood pressure. More study is needed to confirm whether these effects all work together.

Reduce your risk of diabetes

The flavanols in cocoa are thought to increase insulin sensitivity, which over the long run might reduce the risk of diabetes.

Lower blood pressure 

One review study found that eating dark chocolate helped to reduce blood pressure, though in small amounts. Other research found that it improved blood vessel flexibility and function and possibly prevents arteriosclerosis, which is stiffness in your arteries caused from buildup of plaque and fats.

Improve vision

One small study found that people who ate dark chocolate had improved vision 2 hours later compared to people who ate milk chocolate instead. It's not clear how long this effect might last or whether this might work in the real world. A similar small study did not show the same effects on vision from eating dark chocolate. We need much more research into this possible benefit. 

You’ll get the most flavanols from eating chocolate that’s 70% or more dark. Dark chocolate contains a little fiber along with minerals, including:

  • Magnesium
  • Zinc
  • Iron
  • Phosphorus
  • Copper

Nutrients per serving

One-quarter cup of dark chocolate, about 1.5 ounces or 2 large squares, contains:

  • 220 calories
  • 2 grams of protein
  • 13 grams of fat
  • 24 grams of carbohydrates
  • 3 grams of fiber
  • 18 grams of sugar
  • 3 milligrams of cholesterol
  • 9 milligrams of sodium

Potential risks

Dark chocolate has a lot of sugar, fat, and calories, so it's best to enjoy it in moderation. The American Heart Association recommends that you consume no more than 25-36 grams of added sugar per day, depending on your gender and size.

An ounce or 2 per day is more than enough to get the health benefits.

Chocolate bars vary in size and weight, so check the label to see how many ounces are in one portion. And note other ingredients, like caramel, that can add extra sugar and fat. 

Dark chocolate and heavy metals

Some dark chocolate bars contain lead and cadmium. A Consumer Reports study of several brands found that 23 of the 28 bars tested had levels of lead and cadmium higher than the safe maximum daily dose. Even some organic dark chocolate bars contained these metals, which are also found in small amounts in other foods like sweet potatoes and spinach.  

These heavy metals can cause health problems, ranging from stomach irritation to developmental delays, in children and adults. 

Dark chocolate is common in treats like:

  • Candy bars
  • Cakes
  • Hot drinks
  • Puddings
  • Cookies

If you're baking with dark chocolate, the best way to melt it is slowly in the microwave. Chop it into chunks and melt it in 30-second increments, stirring between each one. Melting it on the stove in a double boiler works well, too. It's just not quite as fast. 

Here are a few other ideas for adding small servings of dark chocolate to your diet:

  • Serve a few small squares with fresh fruit.
  • Stir some melted dark chocolate into your morning oatmeal.
  • Add 1 or 2 tablespoons of dark chocolate and a frozen banana to your blender and whip up a nondairy substitute for chocolate ice cream.

Even though dark chocolate has a lot of possible health benefits, you still might want other options. Here are a few.

Carob is a dark brown pod that grows on the carob tree, which is from the Mediterranean. Its pulp is ground into a powder and is a popular substitute for chocolate in baking.

It's low in fat, high in fiber, and has no caffeine.

Cacao nibs are crushed cocoa beans that taste chocolatey but bitter. They're high in fiber and protein, and they give you a nice shot of antioxidants, as well. Try adding them to your granola, smoothie, or baked goods. Or top your next bowl of ice cream with a few tablespoons for a little added crunch.