The Associated Press
MUNICH, Germany - There's more good news for chocolate lovers.
Scientists have found that eating dark chocolate appears toimprove the function of important cells lining the wall of bloodvessels for at least three hours.
The study, involving 17 healthy young volunteers who agreed to eata bar of dark chocolate and then get an ultrasound, found that eatingdark chocolate seemed to make the blood vessels more flexible, whichhelps prevent the hardening of the arteries that leads to heartattacks.
But experts cautioned that the weight gain from eating a lot ofchocolate probably would cancel out the apparent benefit.
Dark chocolate is rich in flavonoids, which act as naturalantioxidants - chemicals that combat the damage oxygen does to thebody. However, that does not mean that chocolate binges will ward offa heart attack, experts warn.
Cacao, the plant that chocolate comes from, has for centuries beenused for everything from medicine to currency. Although enjoyedworldwide, until recently it was considered a treat that provided fatand calories but no substantial nutritional value.
Studies recently have indicated that it releases the happychemical seratonin in the brain.
However, during the last few years, studies have suggested - muchto the delight of chocoholics - that it is rich in flavonoids.
The latest study, conducted by cardiologists at Athens MedicalSchool in Greece, set out to test whether chocolate affected thefunctioning of the so-called endothelial cells in the walls of theblood vessels, which are believed to be affected by oxygen damage andare considered a mirror of the overall health of the cardiovascularsystem.
The scientists, who presented their work Sunday at Europe's mostimportant cardiology conference, gave 3.5 ounces of either dark,bittersweet, chocolate or fake chocolate to 17 healthy volunteers.
On another day, the volunteers were switched. They had nochocolate outside of the study, and investigators did not know whateach volunteer ate during the study.
An ultrasound was taken of each volunteer's upper arm to see thefunctioning of the endothelial cells in the main artery. The cellsaccomplish their goal of controlling the stiffness of the bloodvessel by secreting several active substances that regulate theflexibility of the vessel and influence clot formation.
'During the chocolate session, endothelial function was improved,whereas during the placebo day there were no such changes,' the studyconcluded. 'The favorable effects of dark chocolate lasted for threehours at least.'
By improving the blood vessel flexibility in apparently healthypeople, dark chocolate emerges as perhaps a power food, thescientists said.
'At this time, we do not know whether regular intake of darkchocolate or other cocoa beverages could result in a reduction oftotal cardiovascular' problems or death, the study said.
Experts warned against gorging on chocolate as a way to ward offheart trouble, reminding that excess calories lead to weight gain,which is a powerful trigger of heart problems. Any benefit to bloodvessel flexibility would probably be wiped out by the danger of theweight gain, they advised.
Also, while antioxidants in theory help keep the heart healthy andlooked promising in early research, recent rigorous studiesinvestigating whether antioxidant pills such as vitamins A, C and Eward off heart attacks have shown them to be useless.
Dr. Michael Gibson, associate chief of cardiology at HarvardUniversity-linked Beth Israel Hospital in Boston, said the chocolatestudy was 'interesting.'
'There are a few basic science reasons why this might be good, butkeep in mind that antioxidants also improved forearm blood flow butthat didn't necessarily pan out as an effective treatment,' saidGibson, who was not associated with the study.
