Although catechin is found in several plants, none contain sufficient amounts to reach the levels used in trials; thus, catechin supplements are needed. However, because of its potential to cause side effects on rare occasions [Conn HO. Cyanidanol: will a hepatotrophic drug from Europe go west? Hepatology 1983;3: pp.121–3], catechin should be used only under medical supervision.
There is one natural source of epicatechin that appears to have health benefits. Small daily doses of flavonoid-rich dark chocolate eaten over a two-week period have been found to help the blood vessels to better dilate, according to a recent study. Scientists targeted epicatechin, a specific flavonoid that was absorbed at high levels in the blood, to be particularly beneficial in blood vessel functions. Researchers believe elevated levels of epicatechin trigger the release of active substances that increase blood flow through arteries and improve heart health.
The beneficial effects of chocolate have been shown previously to improve the inner lining of blood vessels after a single use or several uses over a few days.
During the double-blind study, 11 of 21 patients received 1.6 ounces of flavonoid-rich chocolate everyday for two weeks. The rest ate chocolate with low flavonoid content.
At the end of the trial, those who ate flavonoid-rich chocolate had a better reading of flow-mediated dilation, a marker for determining heart disease risks, than those who didn’t. Researchers also determined concentrations of the cocoa flavonoid epicatechin rose significantly in blood samples taken from those who received high-flavonoid chocolate too.
Dark chocolate has been found to have more flavonoids than any food tested so far, including blueberries, red wine and black and green teas.
Because the standard manufacturing of chocolate eliminates as much as half of its flavonoids, some firms have lowered heat and alkalization that preserves up to 95% of chocolate flavonoids. The study also suggested eating chocolate with at least a 70% cocoa content, in moderation, can be beneficial in conjunction with exercise and a healthy diet. [Eurek Alert June 1, 2004]