Here's some good and bad news for chocoholics:
Dark chocolate seems to lower blood pressure, but
it requires an amount less than two Hershey's Kisses
to do it, a small study suggests. The new research
from Germany adds
to mounting evidence linking dark chocolate with
health benefits, but it's the first to suggest that
just a tiny amount may suffice.
Volunteers for the study ate just over 6 grams
of dark chocolate daily for almost five months
one square from a German chocolate bar called Ritter
Sport, equal to about 1 1/2 Hershey's Kisses. People
who ate that amount ended up with lower blood
pressure readings than those who ate white
University of Cologne
researcher Dr. Dirk Taubert, the study's lead author,
said the blood pressure reductions with dark chocolate
were small but still substantial enough to potentially
reduce cardiovascular disease risks, although study
volunteers weren't followed long enough to measure
The research involved just 44 people aged 56 through
73, but the results echo other small studies of
cocoa-containing foods. Cocoa contains flavanols,
plant-based compounds that also are credited with
giving red wine its heart-healthy benefits.
One problem is chocolate bars containing cocoa
tend to have lots of calories, so Taubert and his
colleagues tested small amounts containing just
30 calories each.
The study appears in Wednesday's Journal
of the American Medical Association. It was
funded by University Hospital in Cologne.
The results are interesting but need to be duplicated
in larger, more ethnically diverse populations,
said Dr. Laura Svetkey, director of Duke University's
She stressed that the study results should not
be viewed as license to gorge on chocolate.
"I would be as happy as the next person if I got
to eat more chocolate," she said, but cautioned
that weight gain from eating large amounts of dark
chocolate would counteract any benefits on blood
Study participants were otherwise healthy and mostly
normal-weight German adults with mild high blood
pressure or pre-hypertension, which includes readings
between 120 over 80 and 139 over 89.
Average blood pressure at the start was about 147
Every day for 18 weeks, the volunteers were instructed
to eat one-square portions of a 16-square Ritter
Sport bar, or a similar portion of white chocolate.
White chocolate doesn't contain cocoa.
Systolic blood pressure,
the top number, fell an average of nearly three
points and diastolic dropped almost two points in
the dark chocolate group, compared with no change
in blood pressure readings
in the white chocolate group.
Tests suggested that steady exposure to dark chocolate
prompted chemical changes that helped dilate blood
vessels and regulate blood pressure, the researchers
Participants were told not to eat other cocoa-containing
products and to continue regular eating habits and
activity levels. They also kept food diaries so
researchers could see if other foods might have
influenced the results.
But, said Taubert, "It is very unlikely that other
factors may explain the blood pressure reduction."
Dr. Lawrence Appel of Johns Hopkins School of Medicine
said the most proven non-drug methods for lowering
blood pressure are losing weight and eating less
salt. Eating dark chocolate might help if combined
with those two, he said.
For most people, "the lower your blood pressure,
the better you are. So if you can get it lower from
different strategies that's good for the long term,"