Could Dark Chocolate Help Reduce the Risk of Type 2 Diabetes?

A new study published in the BMJ found that eating dark chocolate was associated with a 21% lower risk of developing type 2 diabetes. Milk chocolate, on the other hand, was not linked to a lower risk of type 2 diabetes and was actually associated with long-term weight gain. While more research is needed on the connection between dark chocolate and diabetes, experts say dark chocolate is always a healthier choice than milk chocolate.

Investigating Dark Chocolate and the Risk of Type 2 Diabetes

For the new BMJ study, researchers collected data from more than 192,000 people who filled out surveys to detail how often they ate different types of chocolate. Over decades of follow-up, the results showed that people who ate more than five servings of dark chocolate each week had a 21% lower chance of developing diabetes as compared to those who didn't or rarely ate dark chocolate.

The study also found that eating more milk, but not dark chocolate, was associated with gaining more weight over time. This is important because long-term weight gain is a risk factor for type 2 diabetes.

The Research Has Limitations, Experts Say

While the study's findings are intriguing, there are still a number of questions left unanswered when it comes to the connection between type 2 diabetes and dark chocolate. For one, the study is observational, which makes it impossible to determine whether dark chocolate is actually causing the reduction in type 2 diabetes risk (or if there's some other factor at play).

Plus, the study population may not be representative of the standard U.S. population. The people in the study ate chocolate less often than the general population does on average, and they were primarily non-Hispanic white adults over the age of 50 at baseline. This might limit the generalizability of the findings.

Another limitation is the fact that the study relied on food frequency questionnaires, which ask participants to remember how often they ate certain foods over the past year. Some researchers have raised concerns about the accuracy of these questionnaires.

Is Dark Chocolate Actually Lowering Type 2 Diabetes Risk?

It's true that dark chocolate is a healthier option—at least compared to milk chocolate—because it contains more cocoa and flavonols. Cocoa is rich in bioactive compounds such as flavonols, which are known to improve insulin sensitivity and have antioxidant and anti-inflammatory properties. Other observational studies have found that people who eat foods rich in these micronutrients have a reduced risk of type 2 diabetes.

However, experts caution that we don't know if dark chocolate is responsible for this effect. Observational studies like this one often show associations but cannot definitively prove cause and effect. While the study may suggest a link between dark chocolate consumption and a reduced risk of type 2 diabetes, further research—particularly randomized controlled trials—is needed to establish a causal relationship.

Should You Add Dark Chocolate to Your Diet?

Though the study found that people who ate dark chocolate had a lower risk of developing type 2 diabetes, it doesn't necessarily mean you should add more chocolate to your diet. As a registered dietitian, I wouldn't prompt my patients to start eating chocolate if they aren't chocolate eaters. But I would encourage milk chocolate eaters to try dark chocolate instead.

Fruit is another unprocessed, sweet option for dessert that is both nutrient-dense and delicious. Dark chocolate can offer benefits when consumed in moderation, but overconsumption may lead to excessive calorie intake, negating those benefits. The key takeaway is that balance and moderation are essential.