Is Dark Chocolate Good for Your Heart?

Partly: dark chocolate may support heart health when eaten in moderation as part of a heart-healthy diet, because cocoa flavanols may help blood vessels function.

Is dark chocolate a heart-healthy choice?

Dark chocolate can fit into a heart-healthy eating pattern, but it is not a proven way to prevent heart disease. Its potential benefits need to be weighed against the added sugar and saturated fat in the product you choose.

The overall pattern of your diet matters more than any one food. Vegetables, fruit, whole grains, legumes and unsalted nuts are useful foundations; the best foods for heart health offer a broader place to start. You do not need to eat dark chocolate to have a heart-healthy diet.

How might dark chocolate help the heart?

Cocoa contains flavanols, plant compounds that may support the function of the endothelium, the lining of blood vessels. A healthy endothelium helps blood vessels respond to the body’s needs, including by relaxing to allow blood to flow.

That possible effect is not the same as a demonstrated reduction in heart attacks or strokes. It also does not mean that every dark chocolate bar has enough flavanols to produce a measurable effect.

Cocoa content and flavanol content are not interchangeable. Processing can affect flavanols, and the amount in a finished dark chocolate product may not be stated on its label. Products used in cocoa research may therefore differ from the dark chocolate sold in a store.

What does the evidence show?

A 2017 review of cocoa and dark chocolate research in people with diabetes described small studies suggesting potential cardiovascular benefits. The review also called for large randomized controlled trials to clarify whether cocoa-containing diets reduce complications in people with diabetes.

This is limited evidence, not proof that eating dark chocolate prevents cardiovascular disease. Research on cocoa or cocoa-containing diets does not automatically establish an effect for an ordinary dark chocolate bar. Results in people with diabetes also cannot automatically be assumed to apply to everyone else.

The available evidence does not establish a reliable amount or a particular product to eat for heart protection. Improvements in a blood-vessel measurement, if observed, would still need to be distinguished from evidence that people have fewer heart attacks, strokes or other cardiovascular complications.

How can you include dark chocolate safely?

Treat dark chocolate as an optional food rather than a heart treatment. If you enjoy it, have a small portion as an occasional dessert instead of adding it solely because you hope it will protect your heart.

Read the nutrition label and compare added sugar, saturated fat and calories. A package may contain more than the serving shown on the label, so check the amounts against the portion you actually plan to eat. Consider how that portion fits with the rest of your meals rather than judging the bar by its front label alone.

A higher cocoa percentage tells you more of the product comes from cocoa ingredients, but it does not tell you precisely how much flavanol is present. Likewise, a sugar-free label does not establish a heart benefit or guarantee that the product is low in saturated fat.

Food is only one part of a heart-healthy routine. For a related part of that routine, see the best drinks for heart health.

Who should be careful, and when should you see a doctor?

If you have heart disease, high blood pressure, high cholesterol or diabetes, ask your clinician or a registered dietitian how dark chocolate fits your care plan. This is especially helpful if you have been advised to limit saturated fat or added sugar. Dark chocolate should not replace prescribed medicines or other recommended care.

Dark chocolate contains caffeine, which can disturb sleep in people who are sensitive to it. If you are pregnant or breastfeeding, ask your clinician how chocolate fits into your overall caffeine intake.

Seek medical advice about symptoms or concerns rather than trying to manage them with a food. If you have new, unexplained chest pain or pressure, especially with sweating, nausea, shortness of breath, or pain spreading to an arm or your jaw, call emergency services immediately. Sudden severe shortness of breath also needs emergency attention.