A new study released this week in Neurology contains good news for chocolate lovers: research conducted in Sweden has found a positive correlation between men who consume large amounts of chocolate with a reduced tendency toward strokes. While the connection between chocolate and health has been illustrated before by past studies, this new research brings focused attention to the correlation due to the sample size of the men observed and the clear connection between chocolate consumption and reduced risk of stroke.
The numbers are striking: an analysis of the results of the study that involved over 37,000 men and women found that those who consumed the most chocolate had a 17% lower chance of suffering from a stroke, while a meta-analysis raised this figure to 19%. Researchers however were quick to point out that this was simply an ‘observational study’, and that further research will have to be done to conclusively prove the connection.
This correlation was culled from the study of the Cohort of Swedish Men, a research project that began in 1997 and included men and women from the ages of 45 to 79. They were initially asked to rate their nutrition habits and lifestyles, and then closely monitored to see how their health changed over time. Chocolate consumption was in turn broken down into four categories, ranging from never eating chocolate each day to the highest category of three times daily or more.
The researchers linked their study to hospital discharge registers, and consequently were able to determine the sources of illness or death. Strokes were classified as cerebral infarction, intracerebral hemorrhage, subarachnoid hemorrhage, and unspecified stroke. Of the 1995 participants that died of stroke between 1998 and 2007, there were 1511 cerebral infarctions, 321 hemorrhagic strokes, and 163 unspecified strokes.
However, researchers were quick to point out the limitations of the study. For one, the comparison is based on a one time observation of the men’s dietary choices, and does not reflect possible changes over time. Secondly, the type of chocolate consumed was not determined. Traditionally people have associated dark chocolate with the greatest health gains, but in Sweden most people eat milk chocolate. As such, the researchers appended a warning that people should not immediately begin to consume large amounts of chocolate, because this would in turn involve eating high levels of sugar and fat, which may bring about their own health problems.
Despite these warnings, the researchers did speculate on the potential cause of this decreased chance of stroke, and stated that the reason could be because of the presence of flavonoids in the chocolate. These could provide protection against cardiovascular disease due to being powerful antioxidants and anti-inflammatories. Further, flavonoids can help reduce blood pressure, increase the amount of HDL cholesterol (commonly known as ‘good’ cholesterol) and improve endothelial function. There are also trace amounts of caffeine in chocolate, which are another rich source of antioxidants.
This is not the first time that chocolate has been connected to a reduced chance of stroke. Dr. Gustavo Saposnik of the University of Toronto, Ontario ran his own study on the connection and presented his results to the American Academy of Neurology 2010 Annual Meeting. There he and his team announced that they had discovered a 22% reduction in risk for subjects that consumed a serving of chocolate once a week, which improved to a 46% reduction in risk for strokes when the subject consumed a 50g sample of chocolate versus none at all.