The Benefits of Chocolate for Heart Health

When you think of a heart-healthy diet, a piece of chocolate might not be the first thing you'd add to the list.

However, researchers are looking at whether chocolate has health benefits—especially for the cardiovascular system.

This article will go over some of the studies on chocolate and heart health, including the potential benefits and downsides of including chocolate in your diet.

Research

Some research has shown a possible link between eating chocolate and better cardiovascular health.

Most of the studies were observational. That means the researchers looked at data but did not try to change or test it.

The findings from this type of study can help scientists come up with theories, but they do not prove that there is a cause-and-effect relationship between factors.

Researchers can take a more active role in other kinds of studies. For example, in a controlled trial, researchers don't just observe—they test a theory by having people do (or not do) certain things, like taking a specific medication.

The evidence from these types of studies can provide stronger evidence of a cause-and-effect relationship between factors—or show that there likely isn't one.

Compared to observational studies, there haven't been as many experimental studies testing a link between heart health and chocolate.

Evidence of Benefits

Some studies have shown that chocolate consumption is linked to factors that we already know can be beneficial for heart health, like lower blood pressure.

These studies do not prove that eating chocolate directly improves cardiac health, but they do show that there could be an interesting link between the two.

• A 2010 study found that women who ate chocolate had a significantly reduced risk of developing heart failure.
  
• In 2011, a meta-analysis of studies published in the British Medical Journal found that chocolate consumption was associated with a 39% reduced risk of cardiovascular disease and a 29% reduced risk for stroke.
• A 2012 study trial showed that daily chocolate intake over a 4-week period was linked to better vascular function in people with congestive heart failure (CHF).
• A 2012 study on people with high blood pressure and metabolic syndrome found that eating up to 100g of dark chocolate per day was linked to a lower risk of cardiovascular events.
• A 2015 study of 21,000 people who were followed over 12 years found that the people who ate the most chocolate had an 11% lower incidence of coronary artery disease and a 25% lower incidence of cardiovascular death compared to people who did not eat chocolate.
• A 2016 study of more than 60,000 Swedish adults linked eating chocolate with a lower risk of heart attacks and ischemic heart disease.
• A 2017 study found that eating dark chocolate with almonds improved blood lipid levels, such as cholesterol, in people with overweight and obesity.

No Evidence of Benefits

There have also been studies that did not find any evidence of heart health benefits from eating chocolate.

• A 2018 study on more than 83,000 post-menopausal women found no evidence of a link between chocolate consumption and a lower risk of heart disease or stroke.
• A 2019 review and analysis of research concluded there was only weak evidence of a link between chocolate consumption and positive health outcomes.
• Another 2019 review of studies concluded there was not enough high-quality evidence to support the idea that eating dark chocolate was responsible for health benefits as opposed to other factors.
• A 2020 study on healthy young women did not find evidence that eating chocolate was linked to heart rate variability, which is a measure of cardiovascular health.
• A 2021 review of studies—including trials to test chocolate's effect on factors related to heart health—did not find strong evidence of cardiovascular benefits.

Mixed Findings

Some studies have not reached firm conclusions one way or the other about the possible heart health benefits of chocolate.

• A 2017 study of more than 30,000 Swedish men found that while eating chocolate was linked to a lower risk of heart failure, the potential protection was not observed in men who ate more than one serving of chocolate a day.
• A 2020 study of postmenopausal women did not find that chocolate intake was linked to better cardiovascular health—however, the study also didn't note any adverse effects.
  
• A 2021 study of more than 180,000 veterans found that chocolate intake was only linked to a lower risk of cardiovascular disease in veterans that had type 2 diabetes.

Making Sense of the Research

If you're trying to look at the research on chocolate's health benefits, know that there are some limitations to these studies and how they are done.

For one, observational studies can be misleading. Just because there is a connection between two things doesn't mean there is a cause-and-effect relationship.

The "gold standard" of research is a randomized, placebo-controlled clinical trial. Until more of these types of studies are done, we won't really know if chocolate truly has health benefits.

The Role of Flavanols

Researchers think that the flavanols in chocolate might be the key to its potential heart health benefits.

Flavanols have many important jobs in the body that relate to cardiovascular health. For example, they can make blood vessels more elastic, improve insulin sensitivity, reduce the "stickiness" of platelets, and help lower blood pressure.

Dark chocolate contains more flavanols than lighter chocolates, like milk or white. Therefore, most of studies use dark chocolate rather than other kinds.

However, that doesn't necessarily rule out that other kinds of chocolate have health benefits, too.

The 2011 analysis published in the British Medical Journal found that dark and light chocolate—in the form of chocolate bars, chocolate drinks, or chocolate confections—were associated with cardiovascular benefits.

The 2015 study in the journal Heart, which followed 21,000 people for 12 years, also found that milk chocolate and dark chocolate appeared to have similar heart-health benefits.

How Much Chocolate Should You Eat?

There is no set amount of chocolate that you need to eat to get the possible cardiovascular benefits.

Most studies suggested a range of chocolate intake. You might get benefits from eating 30 to 100 grams of chocolate per day, or from consuming some form of chocolate a few times a week.

The recommendations also depend on other factors, such as age, sex, and other health conditions.

When researchers have tried to agree on a "sweet spot," many have settled on enjoying chocolate once or twice per week.

The Downsides of Chocolate

There are several possible disadvantages to adding chocolate to your diet, even in light of the possible health benefits.

Extra Calories, Fat, and Carbs

The calories in chocolate can quickly add up: 100 grams of dark chocolate is about 500 calories.

If you were to add 100 grams of chocolate to your daily diet—the upper amount suggested by studies—you would take in enough extra calories in a week to potentially gain weight.

Keep in mind that most chocolate treats also have a lot of fat and carbohydrates. Chocolate can also be very high in added sugar.

If you're following a low-fat or low-carb eating plan, trying to lose or maintain weight, or you want to limit your intake of added sugars, chocolate may not help you reach these goals.

Processed Products

Even if you include chocolate in your diet in moderation, you still may not be getting the health benefits—it depends on the products you choose.

Most chocolate and cocoa products—even dark chocolate—have been processed in a way that removes most of the flavanols.

Until manufacturers begin labeling their products with flavanol content, there is no good way to know if the one we're enjoying will offer the benefits of flavanols.

Summary

Some research has suggested that when enjoyed in moderation, some kinds of chocolate may have heart health benefits.

Chocolate and cocoa that have not been highly processed may contain flavanols, which have been shown to have cardiovascular health benefits. However, many other foods, like tea and berries, also contain these compounds.

To make an informed choice, you'll also want to consider the limitations of the research on the cardiovascular benefits of chocolate and the potential drawbacks of including it in your diet.