3 Health Benefits of Dark Chocolate, According to a Registered Dietitian
Nutrition
As if you needed another reason to enjoy a cocoa treat.
Chocolate is rich in flavour, antioxidants and history.
Research suggests the Maya people were the first to cultivate the cacao plant, which is what cocoa (and chocolate) is made from. In fact, the original rendition of the drink—consisting of cacao, hot water and spices—was known as the "drink of the gods".
In the 16th and 17th centuries, the medicinal properties of cocoa as an expectorant, diuretic, antidepressant and aphrodisiac were proclaimed—claims that are not far off from many of the current benefits of cacao touted today. But before diving into the health benefits of dark chocolate, it's helpful to think of chocolate as an umbrella term. Underneath the umbrella is milk chocolate vs dark chocolate, for instance.
(Related: How to Choose Foods to Foster Muscle Recovery, According to Registered Dietitians)
How Is Chocolate Made?
Cacao is harvested from the Theobroma cacao tree. Once cacao beans are roasted at high temperatures, they become the familiar cocoa beans. Once the cocoa beans have been ground into a fine powder, they're often mixed with ingredients to mitigate the beans' innate bitterness. This includes sugar, milk and other ingredients that result in various percentages of dark chocolate and, of course, milk chocolate.
What Are Some of the Health Benefits of Dark Chocolate?
Chocolate's nutrition comes from its main ingredient, cocoa. When cocoa is minimally processed, it is rich in minerals such as potassium, zinc and magnesium. It also contains flavonoids (naturally occurring chemicals in plants with beneficial effects on health), which have potent antioxidant properties.
However, the type of dark chocolate you buy matters. For instance, a review—found in a 2017 issue of the journal Frontiers in Nutrition—identified that most of the research supporting the health benefits of dark chocolate has been done on options that are made of up to 80 percent cocoa. For context, dark chocolate contains anywhere from 50 to 95 percent cocoa solids.
Here are the three top health benefits of dark chocolate.
3 Health Benefits of Dark Chocolate
1.May Support Cardiovascular Health
Noshing on dark chocolate may have a positive impact on cardiovascular health—and in many different ways. Here's why: chocolate that contains high percentages of cocoa may have a beneficial effect on heart health by lowering blood pressure, improving blood-vessel function and possibly even lowering lipid profiles (cholesterol and triglyceride levels).
A 2019 randomised control trial showed that in a group of healthy young adults, eating dark chocolate made of 90 percent cocoa every day for 30 days improved blood-pressure values compared with those who consumed dark chocolate with lower concentrations of cocoa. Pro tip: Having normal blood-pressure values is critical for good health. High blood pressure can negatively affect your health by damaging blood vessels and causing the heart to do extra work.
As far as lipid levels go, a meta-analysis published in a 2011 issue of The European Journal of Clinical Nutrition found that regular consumption of dark chocolate decreased low-density lipoprotein, or LDL, cholesterol levels. LDL is one of the forms of cholesterol commonly known as "bad cholesterol", and when LDL levels are higher than normal, the risk of heart disease and stroke is higher.
2.May Help Improve Mood
If you've ever reached for some chocolate when you were in need of comfort, know that you're not alone. While the sweet taste and decadent texture of the treat may be the main reason why you feel better after enjoying it, there are also legitimate scientific reasons behind dark chocolate improving mood.
Take, for example, a randomised control trial (published in a 2022 issue of The Journal of Nutritional Biochemistry) that studied the effect dark chocolate had on mood in healthy adults aged 20 to 30 years old. In the study, the participants either consumed 30 grams of 85 percent or 70 percent dark chocolate each day for three weeks. The control group didn't consume any dark chocolate.
To put 30 grams of chocolate into perspective, that is about one-third of a traditionally sized dark-chocolate bar. What did the researchers find? Those who consumed the 85 percent dark chocolate experienced a significant reduction in feelings of emotional distress, compared with those who only had the 70 percent dark chocolate and the control group. One explanation of this result could be due to the positive effects 85 percent dark chocolate has on the gut microbiome.
Aside from its ability to promote the health and diversity of the gut microbiome, cocoa may beneficially support mood because it's a rich source of polyphenols (naturally occurring beneficial compounds found in plants). Polyphenols have antioxidant properties that can affect mood by lowering inflammation, which is thought to contribute to depression.
A large epidemiological study, published in a 2018 issue of the journal Molecules, suggested that those who followed a diet containing high amounts of polyphenols experienced a reduction of depressive symptoms. One possible reason for this could be that the consumption of dark chocolate lowers cortisol levels. The lowering of these stress-hormone levels may, in turn, help decrease symptoms of anxiety and depression.
3.May Support Balanced Blood-Sugar Levels
It might seem counter-intuitive to suggest that you can improve blood-sugar control by eating chocolate, but that's the idea. But before you go running to the shop and buy chocolate in the name of health, remember that most chocolate bars are high in sugar and low in polyphenols—these particular bars will not help regulate blood sugar.
The research on dark chocolate supporting blood-sugar balance is mixed, and more studies need to be done. However, it appears that the polyphenol content in dark chocolate can help improve insulin sensitivity. At the very least, if you are concerned about your blood-sugar levels, choosing dark chocolate will probably not have an effect on fasting insulin levels compared with chocolate with a lower cocoa percentage.
For perspective, insulin levels that are consistently high may cause cells to become insulin resistant, which means they can no longer take up glucose from the blood. Insulin resistance can lead to a variety of chronic diseases, so keeping insulin levels controlled is important for optimal well-being.
The Bottom Line
At the end of the day, enjoying chocolate in any form can be part of a rich and balanced diet. Choosing a dark chocolate—preferably one that is at least 80 percent cocoa—can have some benefits for your health. It's important to remember that consuming a diet that includes fruits, vegetables, protein, healthy fats and fibre, and engaging in exercise and proper sleep hygiene, are critical to longevity.
Words by Sydney Greene, MS, RDN.