Eating up to 100 g of chocolate a day is associated an 11% lower risk of heart disease and a 25% lower risk of associated death compared to not eating chocolate, according to a study published online June 15 in the journal Heart.
In addition, the highest chocolate intake was associated with a 23% lower risk of stroke, even after taking into account other potential risk factors, revealed the prospective study of almost 21,000 people who are participating in the long-term EPIC-Norfolk study.
“Somewhat surprising” to the researchers was that “milk chocolate was more frequently consumed than dark chocolate in this cohort,” and yet, “we still observed a reduced risk of CVD,” according to the study.
They explained this contradicted their expectation, based on research literature, that the “benefits of chocolate consumption would be mainly associated with dark chocolate, rather than the commercially available products generally used in British population, which are high in sugar content and fat.”
While the researchers did not publish the specific data related to dark verses milk chocolate consumption, they suggested the unexpected result “may indicate that not only flavonoids, but also other compounds – possibly related to milk constituents such as calcium and fatty acids – may provide an explanation for the observed association.”
The researchers acknowledge, however, little is known about the mechanism for action and suggest additional study on the topic is necessary. If future research supports the connection with milk constituents, there may be other ways to reap their benefits, such as through other foods or supplements, that have lower amounts of sugar and saturated fat.
Link is not causal
While the association between higher chocolate consumption and reduced risk of heart disease and stroke are significant, they are not causally linked in this study, emphasize the researchers who were led by Chun Shing Kwok of the School of Medicine and Dentistry, University of Aberdeen.
The research is based on food frequency questionnaires, which are a valid research tool, but which also are limited because they are based on self-reporting and recall.
“It is possible that lower CVD rates among people who report consuming more chocolate might be due to differential underreporting of chocolate intake in those with potentially greater CVD risk, such as the obese and physically inactive,” the researchers acknowledged.
Potential support for this argument is that people who consume higher amounts of chocolate tended to be younger, have lower BMI, lower waist-hip ratios, lower systolic blood pressure and be more regularly physically active – “all of which add up to a favorable cardiovascular disease risk profile,” according to a release discussing the study.
This observation also raises questions about whether the association could be explained by reverse causation “in that people with a higher risk profile, including those with obesity, diabetes mellitus or prevalent CVD, eat less chocolate-containing foods than people who have a perceived healthy risk profile,” the researchers note in the study.
The findings are further limited to Caucasians because of the study’s population, add the researchers.
Despite these limits, the researchers conclude: “There does not appear to be any evidence to say that chocolate should be avoided in those who are concerned about cardiovascular risk.”