Dark Chocolate Plus Plant Sterols Reduces Cholesterol and Blood-Pressure Levels

The regular consumption of a chocolate bar with added plat sterols can lower total- and LDL-cholesterol levels as well as reduce systolic blood pressure, a new study has shown. The benefits of eating the chocolate, a dark chocolate product supplemented with plant sterols, occurred without any weight gain, suggesting the cocoa-flavanols-rich treat might be helpful in the dietary management of cardiovascular risk, say investigators. Senior investigator Dr John Erdman (University of Illinois, Urbana-Champaign) stated that the specialized chocolate bars, which are supplemented with plant sterols in addition to the naturally occurring cocoa flavanols, are likely to be consumed by individuals looking to make healthier choices. The product is now available in US stores, including Walgreen’s and CVS Pharmacy, usually in the same aisle as but separate from regular chocolate candy.

"There are two components of the chocolate bar; the first is that it contains plant sterol esters, which have been added, which have been demonstrated to reduce serum cholesterol," said Erdman. "The second aspect is the cocoa flavanols, which are not added but are present in cocoa and the cocoa bean and preserved in the chocolate bar. The flavanols are what have received the most interest in terms of vascular effects."

Previous studies have shown that the consumption of cocoa-flavanols-containing foods can improve endothelial function, platelet reactivity, and insulin sensitivity and reduce blood pressure, he said. The purpose of this study was to test whether vascular protection with the addition of plant sterols would be observed in a slightly hypercholesterolemic patient population (baseline total cholesterol levels ranged from 202 mg/dL to 284 mg/dL) who regularly ate the chocolate product.

In total, 49 adults followed the American Heart Association’s "Eating Plan for Healthy Americans" diet for two weeks prior to randomization. After the two-week run-in period, the subjects were randomized to two groups, with one eating two of the dark chocolate bars daily, and the other eating two nutrient-matched dark chocolate bars that did not contain plant sterols. Participants consumed the chocolate bar for four weeks and then were switched to the other for an additional four weeks.

Regularly eating the plant-sterol-containing chocolate bar reduced total cholesterol 2.0% and LDL cholesterol 5.3%, both significantly. This reduction was on top of the 7% reduction in total cholesterol that occurred during the two-week dietary run-in phase. Consumption of the chocolate product also reduced systolic blood pressure 5.8 mm Hg at eight weeks.

Dr. Erdman said the extent of the reduction in blood pressure was surprising, and the reduction is likely attributed to cocoa flavanols increasing the synthesis of nitric oxide. The Kuna Indians, he noted, an indigenous population in Panama, consume a large amount of cocoa rich in flavanols, and despite a diet that also has a large amount of salt, have a very low prevalence of hypertension and cardiovascular disease mortality.

Erdman said that because Mars funded the study, which he said wouldn’t have been done if the company hadn’t, there are some who will be quick to dismiss the results. Sponsorship from the food industry, he said, is looked upon more disparagingly by some in the scientific community than sponsorship from drug companies, something he doesn’t exactly understand. "We’ve run cholesterol studies in the past, and I can tell you we ran this study just like we ran any other trial," he said.

The CocoaVia chocolate bar contains about 100 calories and 6 g of total fat. Mars Inc sponsored the study. Erdman is a consultant and chairs the Mars Scientific Advisory Council. Mars also employs Dr Catherine Kwik-Uribe, one of the authors of the paper.

Allen RR, Carson L, Kwik-Uribe C, et al. Daily consumption of a dark chocolate containing flavanols and added sterol esters affects cardiovascular risk factors in a normotensive population with elevated cholesterol. J Nutr 2008; 138:725-731. Abstract