By E.J. Mundell

SAN DIEGO, Apr 17 (Reuters Health) -- Cocoa, the compound that gives chocolate its deep, rich flavor, may also help prevent cholesterol-related damage to arteries, researchers report.

However, they stress that the cocoa they tested was de-fatted cocoa extract, not the high-fat chocolate found in the average candy bar or cup of hot cocoa.

"Biologically active compounds that are present in cocoa (extract)" appeared to protect rabbit arteries from constricting under the effects of cholesterol, explained researcher Dr. Tissa Kappagoda of the University of California, Davis. His team's findings were presented at the Experimental Biology 2000 conference, held here this week.

Speaking with Reuters Health, Kappagoda explained that cocoa extracts appear to be a good source of antioxidant flavonoids -- plant-based compounds thought to fight the chemical processes that link a high cholesterol level to diseased arteries. Similar compounds found in vegetables, fruits, and tea seem to protect arteries from harm, and the researchers sought to determine if extracts of the cocoa bean might do the same.

To do so, they conducted laboratory tests examining the response to cocoa extract of segments of rabbit aorta (the large artery leading from the heart). Kappagoda explained that healthy aortas retain the ability to relax -- easing blood flow and keeping blood pressure at healthy levels. Cholesterol-related damage to the aorta restricts this relaxation, however, sending blood pressure upwards.

The California researcher reports that exposing aortas to cocoa extract "produced a relaxation" in aortic tissues. This response was noted in aortas taken from rabbits fed either low- or high-cholesterol diets.

He said the response was "totally comparable" to that seen in similar tests of flavonoid compounds from other sources, including fruits, vegetables, and tea.

Although the study received funding from the Mars candy bar corporation, Kappagoda stressed that there is a big difference between the consumption of pure, non-fat cocoa extract and high-fat chocolate bars and hot cocoa drinks. He points out that chocolate manufacturing processes eliminate most natural flavonoids from much of the commercial chocolate available to consumers, and between 40 - 45% of calories in most store-bought coca drinks are from fat.

"As a cardiologist," he said, "I don't recommend (consuming) that, because we usually try and shoot for a much lower fat content, especially for people who have heart disease."

But cocoa lovers can take heart from the fact that, according to Kappagoda, "a couple of companies are looking at this, and they (hope) to produce a low-fat, 'lite' cocoa drink which will have all the good things and reduce the fat -- and still be acceptable from a taste point of view."

(From Reuters health)