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Flavanols in Cocoa Linked to
Cardiovascular Health Benefits
Small amounts of chocolate can lower blood pressure
and reduce the risk of heart disease, according to a
study by German researchers published in the
European Heart Journal.
The authors of the study said that they assessed 19,357 people,
who were aged between 35 and 65, and evaluated their chocolate
consumption for a period of at least ten years.
The researchers said that they found that those who ate the most
amount of chocolate (an average of 7.5 grams a day) had lower
blood pressure and a 39% lower risk of having a heart attack or
stroke compared to those who ate the least amount - an average
of 1.7 grams a day.
Nutritional researchers at the German Institute of Human Nutrition
in Nuthetal, Germany, said that if people in the group eating the
least amount of chocolate increased their intake by six grams a day,
85 fewer heart attacks and strokes per 10,000 people could be
expected to occur over a period of about ten years.
They also believe that if the 39 per cent lower risk is generalized
to the general population, the number of avoidable heart attacks
and strokes could actually be higher because the absolute risk
in the general population is higher.
Though further research is needed, the researchers said that
flavanols appear to be the substances in cocoa that are responsible
for lowering blood pressure and boosting heart health. These
substances appear to improve the bioavailability of nitric oxide
from the cells that line the inner wall of blood vessels:
“Nitric oxide is a gas that, once released, causes the smooth
muscle cells of the blood vessels to relax and widen; this may
contribute to lower blood pressure. Nitric oxide also improves
platelet function, making the blood less sticky, and makes the
vascular endothelium less attractive for white blood cells to
attach and stick around.”
Moderation Is Important
The British Heart Foundation (BHF), in response to the study,
has sounded a note of caution stating that it was important to
recognize chocolate has high amounts of calories and saturated
fat which are linked to weight gain and raised cholesterol levels,
two of the key risk factors for heart disease.
Dietary experts from BHF also warned that it was important
people ensured that eating chocolate did not increase their
overall intake of calories or reduce their consumption of healthy
foods. “Small amounts of chocolate may help to prevent heart
disease, but only if it replaces other energy-dense food, such
as snacks, in order to keep body weight stable,” they said.
How The Study Was Conducted
The participants in the study received medical checks,
including blood pressure, height and weight measurements
between 1994 and 1998. They also answered questions
about their diet, lifestyle and health.
Furthermore, participants were asked how frequently they
ate a 50g bar of chocolate, and the researchers added, that
a question was not included about whether the chocolate
was white, milk or dark chocolate.
However, the researchers said sub-set of 1,568 participants
were asked to recall their chocolate intake over a 24-hour
period and to indicate which type of chocolate they ate to
give indications that might be expected for the complete
study cohort.
In this sub-set, found the researchers, 57 per cent ate
milk chocolate, 24 per cent dark chocolate and two
per cent white chocolate.
The researchers allocated the participants to four groups
(quartiles) according to their level of chocolate consumption.
According to the report, follow-up questionnaires were sent
out every two or three years until December 2006, with the
study participants asked whether they had had a heart attack
or stroke, information which was subsequently verified by
medical records from general physicians or hospitals.
The German researchers found that during the eight years
there were 166 heart attacks (24 fatal) and 136 strokes
(12 fatal) with people in the top quartile having a 27 per cent
reduced risk of heart attacks and nearly half the risk (48 per cent)
of strokes, compared with those in the lowest quartile.
Source: European Heart Journal
Published online:
Title: Chocolate consumption in relation to blood pressure
and risk of cardiovascular disease in German adults
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