New study shows chocolate associated with lower risk of irregular heartbeat


Over the years, research has consistently shown that eating modest amounts of chocolate can help protect the heart.

chocolate bar unwrappedNow there’s more good news for chocolate lovers: A widely publicized study from Beth Israel Deaconess Medical Center provides evidence that regular consumption of chocolate is associated with a significantly lower risk of being diagnosed with atrial fibrillation, a common and potentially life-threatening type of irregular heartbeat that increases the risk of heart failure and strokes.

“Arrhythmias affect millions of people,” says the study’s lead author Elizabeth Mostofsky, ScD, MPH, a member of the Cardiovascular Epidemiology Research Unit at BIDMC and Instructor in Epidemiology at the Harvard T. H. Chan School of Public Health. “It was gratifying for us to discover that an enjoyable activity like moderate chocolate intake could potentially lower a person’s risk of being diagnosed with this serious condition.”

The study, published in the journal Heart, included 55,000 men and women in Denmark.

“Participants answered a questionnaire reporting on their typical chocolate intake,” explains Mostofsky. “This large group was then followed over time to find out who among them was diagnosed with atrial fibrillation.”

The results showed that people who ate chocolate at least once a month had diagnosed rates of atrial fibrillation that were 10 to 20 percent lower than people who ate chocolate less than once a month, even after accounting for other factors that may be related to chocolate intake and heart health.

How might this be happening? It could be connected to chocolate’s high flavonol content.

“Atrial fibrillation is thought to be caused by inflammation that can lead to scarring of heart tissue,” explains Mostofsky (right). “The flavonol antioxidants found in chocolate may help reduce inflammation that leads to tissue damage.”Elizabeth Mostofsky, ScD, MPH

But moderation is key.

“Eating excessive amounts of chocolate is never recommended because many chocolate products are high in sugar, fat and calories and could lead to weight gain and other metabolic problems,” says Mostofsky. “In our study, the lowest rates of diagnosed atrial fibrillation were shown in people who reported eating an ounce of chocolate two to six times per week.”

That would typically be the equivalent of one or two squares from a chocolate bar. And the higher the cocoa content, the better.

“Compared with milk chocolate, dark chocolate has more cocoa solids and chocolate with a higher percentage of cocoa solids generally have higher levels of flavanols that those with lower percentages,” she adds.

Above content provided by the CardioVascular Institute at Beth Israel Deaconess Medical Center. For advice about your medical care, consult your doctor.

July 2017