Chocolate may actually be good for you, suggests new research which confirms previous studies showing the benefits of flavonols found in certain chocolates and cocoa on heart health.
An independently funded study has found that naturally occurring dietary flavonols improve blood vessel function, believed to be an important indicator of cardiovascular health, much like cholesterol levels or blood pressure.
Co-investigator Marguerite M. Engler, professor and vice chair of the Department of Physiological Nursing at the University of California at San Francisco reported the findings yesterday at the American Heart Association Scientific Sessions.
Researchers at the University of California at San Francisco compared the effects of consuming a commercially available flavonol-rich dark chocolate bar (Dove Dark Chocolate made by Mars) with a flavonol-poor dark chocolate product on blood vessel function.
Twenty-one healthy subjects ate 46 grams of either the flavonol-rich (259mg of chocolate flavonols) or flavonol-poor chocolate product each day for two weeks in the randomised, double-blind, placebo-controlled clinical study.
Researchers measured the level of flavonols in participants' blood, and found that the chocolate flavonols in the flavonol-rich chocolate were absorbed into the blood stream. Flow-mediated dilation was also examined as an indicator of endothelial function, using ultrasound (sound waves) to image a blood vessel in the arm called the brachial artery. The endothelium is the inner lining of blood vessels responsible for regulating blood vessel dilation, or relaxation. Flow-mediated dilation is a measure of blood vessel dilation or elasticity in response to an increase in blood flow.
The research team found that the participants who consumed the flavonol-rich chocolate exhibited blood vessel dilation two hours after chocolate consumption, compared to test results at baseline.
"The exciting news here is that blood vessel dilation increased in subjects who ate this commercially available chocolate product," said Dr Engler. "This is consistent with previous research suggesting that certain chocolates do contain enough flavonols to support cardiovascular health."
Flavonols are a sub-class of flavonoids found naturally in a variety of plant-based foods, including certain cocoas, chocolates and red wine. Several previous studies suggest that flavonols may have a host of potentially beneficial health effects.
"As health professionals, we are very excited to find that a food consumers can enjoy eating in moderation may have measurable benefits on health," said Dr Carl L. Keen, professor and chair at the Department of Nutrition and professor at the Department of Internal Medicine at the University of California at Davis, who also presented research at the session. "We've hypothesised that chocolate, if processed properly, could contain enough flavonols to have a beneficial effect on heart health. The study from University of California, San Francisco further reinforces this hypothesis."
While not all chocolate retains the naturally-occurring flavonols, which can be lost during processing of the cocoa, Mars claims to have developed proprietary methods of processing cocoa beans to retain many of the flavonols in their chocolate products. The company marks these products with the Cocoapro logo to signify the careful handling of the cocoa bean.