Chocolate headlines swing between "health food" and "guilty pleasure." The truth sits in between: cocoa contains compounds that may be good for the heart, but most chocolate also comes with a lot of sugar, fat and calories. Here is what the research does and doesn't show.
What's in cocoa
Chocolate is made from the seeds of the cacao tree, roasted and ground into cocoa solids and cocoa butter. Cocoa solids are rich in flavanols, a group of plant compounds (including epicatechin) also found in tea, apples, grapes and berries. In studies, flavanols help blood vessels relax and may modestly lower blood pressure. Cocoa also contains theobromine and a little caffeine, which give a mild lift, and minerals such as iron, magnesium and copper.
The amount of flavanols varies enormously. Dark chocolate has more cocoa solids than milk chocolate, and white chocolate contains none, only cocoa butter. Processing matters too: "Dutch-processed" or alkalized cocoa and heavily roasted products lose much of their flavanols, and labels rarely say how much a bar contains.
What the research shows
- Blood pressure and blood vessels. Short-term trials suggest cocoa flavanols can slightly lower blood pressure and improve blood vessel function. The effects are small.
- Heart disease. The large COSMOS trial, published in 2022, gave older US adults a cocoa extract supplement providing 500 mg of flavanols a day, far more than most people would get from chocolate, without the sugar and fat. It did not significantly reduce total cardiovascular events, though there were fewer deaths from cardiovascular disease, a finding that needs confirming. In 2023, the FDA allowed a qualified health claim for high-flavanol cocoa powder, but described the evidence as very limited.
- Blood sugar. Dark chocolate raises blood sugar less than milk chocolate because it contains less sugar, but it still contains sugar and isn't a treatment for diabetes.
- Mood. Chocolate is pleasurable to eat and can lift your mood for a while, as many enjoyable foods can. That isn't the same as treating stress or depression.
Eating chocolate isn't the same as taking a flavanol supplement, and the potential benefits of cocoa don't cancel out the sugar and calories in a typical bar.
Sugar, fat and calories
An ounce of dark chocolate (70 to 85 percent cocoa) has roughly 170 calories, and milk chocolate a little less but more sugar. Much of the fat is cocoa butter, which is mostly saturated fat, though its main fat, stearic acid, appears to have little effect on LDL cholesterol. Many chocolate bars, candy and desserts also contain added fats, sugar, caramel and other ingredients.
Heavy metals
Cocoa can pick up small amounts of lead and cadmium from the soil and during processing, and tests have found measurable levels in some dark chocolate. Eating a little dark chocolate now and then isn't a concern for most adults, but it is one more reason not to treat it as a daily health food, especially for children and during pregnancy. Varying brands helps.
How to enjoy chocolate
- Choose dark chocolate with a high cocoa percentage if you like it; it tends to be lower in sugar and more satisfying in small amounts.
- Enjoy an ounce or so, savored slowly, rather than a whole bar.
- Unsweetened cocoa powder adds chocolate flavor to oatmeal, smoothies and chili with little sugar or fat.
- Treat chocolate as what it is: a delicious treat that can be part of a healthy diet, not a remedy.
Read more about chocolate, its history, and cooking with chocolate.
Sources
- Effect of cocoa flavanol supplementation for the prevention of cardiovascular disease events: the COSMOS randomized clinical trial (American Journal of Clinical Nutrition, 2022)
Last reviewed November 2026. This article is general information, not medical advice.