"While other studies have looked at how chocolate may help cardiovascular health, this is the first of its kind study to find that chocolate, may be beneficial for reducing stroke in men," said study author Susanna C. Larsson, PhD, with the Karolinska Institute in Stockholm, Sweden.
For the study, 37,103 Swedish men ages 49 to 75 were given a food questionnaire that assessed how often they consumed various foods and drinks and were asked how often they had chocolate. Researchers then identified stroke cases through a hospital discharge registry. Over 10 years, there were 1,995 cases of first stroke.
Men in the study who ate the largest amount of chocolate, about one-third of a cup of chocolate chips (63 grams), had a lower risk of stroke compared to those who did not consume any chocolate. Those eating the highest amount of chocolate had a 17-percent lower risk of stroke, or 12 fewer strokes per 100,000 person-years compared to those who ate no chocolate. Person-years is the total number of years that each participant was under observation.
In a larger analysis of five studies that included 4,260 stroke cases, the risk of stroke for individuals in the highest category of chocolate consumption was 19 percent lower compared to non-chocolate consumers. For every increase in chocolate consumption of 50 grams per week, or about a quarter cup of chocolate chips, the risk of stroke decreased by about 14 percent.
"The beneficial effect of chocolate consumption on stroke may be related to the flavonoids in chocolate. Flavonoids appear to be protective against cardiovascular disease through antioxidant, anti-clotting and anti-inflammatory properties. It's also possible that flavonoids in chocolate may decrease blood concentrations of bad cholesterol and reduce blood pressure," said Larsson.
"Interestingly, dark chocolate has previously been associated with heart health benefits, but about 90 percent of the chocolate intake in Sweden, including what was consumed during our study, is milk chocolate," Larsson added.
The study was supported by the Swedish Council for Working Life and Social Research, the Swedish Research Council/Committee for Infrastructure and the Karolinska Institute.