In the best news yet for chocolate lovers, a new study has apparently shown that dark chocolate can lower blood pressure.
Researchers in the U.S. along with colleagues in Italy, have added to growing research that presents evidence that compounds found in chocolate called flavonoids can help the blood vessels work more smoothly, possibly reducing the risk of heart disease.
Jeffrey Blumberg of Tufts University in Boston, who led the study, says that previous studies suggest flavonoid-rich foods, including fruits, vegetables, tea, red wine and chocolate, might offer cardiovascular benefits, but this is one of the first clinical trials to look specifically at dark chocolate's effect on lowering blood pressure among people with hypertension.
Blumberg says the study results suggest that cocoa flavonoids appear to have benefits on vascular function and glucose sensitivity.
As yet scientists are unable to make specific recommendations for patients based on their research on chocolate, and nutritionists have urged people to be cautious because chocolate is high in fat, sugar and calories.
Blumberg and researchers at the University of L'Aquila in Italy, studied 10 men and 10 women with high blood pressure.The group were divided in two and for 15 days, half ate a daily 100 gram bar of specially formulated, flavonoid-rich dark chocolate, while the other half ate the same amount of white chocolate.
Each group then switched over and ate the other chocolate.
According to Blumberg white chocolate, which has no flavonoids, was the perfect control food because it contains all the other ingredients and calories found in dark chocolate.
The dark chocolate used had a high level of flavonoids, giving it a slightly bittersweet taste, in general most Americans eat milk chocolate, which has a low amount of these compounds.
Blumberg's team say that when the volunteers ate the special dark chocolate, they had a 12 mm Hg decrease in systolic blood pressure (the top number in a blood pressure reading) and a 9 mm Hg decrease in diastolic blood pressure (the bottom number) on average.
When the volunteers ate white chocolate the blood pressure did not change.
Blumberg says that this is not only a statistically significant effect, but it's also a clinically meaningful decline, and the kind of reduction in blood pressure often found with other healthy dietary interventions.
It also appeared that eating dark chocolate seemed to improve how the body used insulin, and reduced low density lipoprotein (LDL) or "bad" cholesterol by about 10 percent on average.
It is important to note says Blumberg that the findings do not suggest that people with high blood pressure should eat lots of dark chocolate in lieu of other important blood pressure-reduction methods, such as medication and exercise, but it does identify specific flavonoids that can have a benefit on blood pressure and insulin sensitivity.
The research is published by the American Heart Association, in the journal Hypertension.