Chocolate Habit Lowers Heart Fibrillation Risk

Doctors had no clue how to prevent, let alone cure, atrial fibrillation, which may affect one in four adults, until a study of Danish chocoholics

Send in e-mailSend in e-mail
Send in e-mailSend in e-mail
Chocolate bars arranged on a plate at Cacao Store, a specialist chocolate store, in Tokyo, Japan, May 10, 2016.
Chocolate bars arranged on a plate at Cacao Store, a specialist chocolate store, in Tokyo, Japan, May 10, 2016. Credit: Akio Kon/Bloomberg

The only news better than “chocolate is good for you” is “eating chocolate regularly is good for you”. A big new study indicates that regular chocolate consumption lowers the risk of developing atrial fibrillation, a.k.a. heart flutter.

The best news of all: the beneficial effect isn’t confined to dark chocolate, beloved by aficionados and secretly disliked by most everyone else. The participants of the study weren’t asked what chocolate they eat. Since the work was done in Denmark and most people there eat milk chocolate, the working assumption is, that’s what they ate.

Milk chocolate in Denmark is defined as having at least 30 percent cocoa solids. Other countries that may define milk chocolate as having half that much, which could affect the efficacy of eating the stuff.

“Regular” doesn’t mean “with every meal.” The study, published in the scientific journal Heart, defines the optimal consumption rate at one serving a week for women, and two to six for men, based on the strongest associations they found with decreased risk of fibrillation.

A serving of chocolate is 30 grams, or one ounce. Elite’s iconic “Cow” chocolate bars sold in Israel are usually 100 grams, which is just over three servings (and it contains 35% cocoa solids, according to its manufacturer). A normal-sized Hershey’s Kiss weighs 0.2 ounces, so a serving of Hershey’s Kisses would be five kisses.

The iconic Cow chocolate.Credit: MySupermarket

The problem is extremely common, and extremely frustrating. One in four adults is likely to develop heart flutter at some point, say the scientists – and the condition is untreatable. Nor have there been hints towards contenders for prevention, until now, which renders this chocolate research quite the breakthrough.

The study by Drs. Sea Pokorney and Jonathan Piccini drew on 26,400 men and 29,100 women aged 50 to 64, from the population-based Danish Diet, Cancer and Health Study. The participants filled out questionnaires on their chocolate habits, and on risk factors for heart disease, to adjust the findings. Then their state of health was monitored, for hospital care (and death), for an average of 13.5 years using national registry data, for hospital treatment or death.

Briefly: In those 13.5 years, after adjusting for heart disease factors, eaters of 1 to 3 servings of chocolate a month had 10 percent less newly diagnosed heart flutters than their abstaining peers (less than 1 serving a month).

The strongest association for women, say the researchers, was a single weekly serving of chocolate, which conferred a whopping 21 percent lower risk. Men got to eat two to six weekly servings, or 60 to 180 grams of chocolate, to achieve their maximal risk reduction, of 23%.

A few caveats. This study is questionnaire-driven, and people lie like they breathe when it comes to diet. Second, the study is observational, making no statement about cause and effect. Nobody is saying that chocolate prevents heart flutter, just that association has been found. Dark chocolate could be better than milk – we don’t know. So could tree frogs.

Thirdly, the sugar in chocolate is more toxic than therapeutic and as for fat, the jury’s still arguing.

But, as the scientists put it: “Despite the fact that most of the chocolate consumed in our sample probably contained relatively low concentrations of the potentially protective ingredients, we still observed a robust statistically significant association.” That is good news.