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Chocolate Contains Healthy Antioxidants
High Levels of Antioxidants Prompt Further Research "Research on antioxidants is only in its infancy," explains Penny Kris-Etherton, Ph.D., professor of nutrition at The Pennsylvania State University and author of research published in The American Journal of Clinical Nutrition. "We already know that increased consumption of fruits and vegetables results in an increase of antioxidants in our blood. We believe chocolate consumption may have the same effect." Antioxidants in the blood stream essentially mop up substances called free radicals, small reactive molecules that cause damage to the body, which scientists believe may be the triggers for serious diseases such as cancer and heart disease. They also may be related to cognitive deterioration that comes with aging. Studies have shown that chocolate contains a very high level of antioxidants, ranking with the top fruits and vegetables for antioxidant content. "When you think of chocolate, you think of a chocolate bar, chocolate chips or something with a cream-filled center," said Kris-Etherton. "We forget that chocolate is derived from cocoa beans - the fruit of the cacao tree - a fruit that is a rich source of these potentially beneficial substances." Research conducted at the University of Scranton has demonstrated that the quality and quantity of the antioxidants in chocolate are very high relative to other common foods and beverages such as black tea, red wine, raisins, strawberries, pinto beans and other plant products. Cocoa powder ranked the highest of the chocolate products, followed by dark chocolate and milk chocolate. Dark chocolate contained about eight times the polyphenol antioxidants as strawberries, which rank high among fruits. Studies continue to indicate chocolate's polyphenols are not only absorbed in the bloodstream, they also may have some positive health benefits. But will eating chocolate help prevent heart disease? Kris-Etherton found that 24 human subjects absorbed antioxidants from a small amount of cocoa powder and dark chocolate added to their diets. The study also yielded exciting results regarding chocolate's effect on blood cholesterol levels. "The results for subjects consuming the dark chocolate and cocoa powder showed that the increased antioxidant levels protected the LDL cholesterol (bad cholesterol) from being oxidized. This is important because it is what starts the process of atherosclerosis. In addition, HDL cholesterol (good cholesterol) levels were increased. Both of these findings are associated with a decreased risk of heart disease," explained Kris-Etherton. Kris-Etherton’s research on chocolate was spurred by earlier studies that suggested chocolate could have some positive antioxidant benefits. In Japan, researchers fed cocoa extract to rabbits and found that it retarded cholesterol oxidation which leads to artery plaque build-up. In another experiment, a phenol compound in cocoa called epicatechin was shown to inhibit the formation of skin tumors in mice. Kris-Etherton said future studies on chocolate's antioxidant activity may include combining cocoa and chocolate with other foods, such as nuts, to determine their biological effect on humans. The latest observations on nuts suggest they may be protective against heart disease. "Chocolate holds the promise of healthful benefits from its antioxidant content," said Kris-Etherton. "Our next steps will hopefully clarify those benefits for all of us who enjoy chocolate." Researchers have recommended that people increase their consumption of antioxidant rich foods, but they caution that more studies need to be done to determine how much of the antioxidants in foods are actually absorbed into the blood. Summary from the June 2nd 2005 International Congress on Antioxidant Methods. The American Chemical Society convened the 2nd International Congress on Antioxidant Methods June 22-24, 2005 in Orlando, Florida. 90 scientists from around the world met to determine how best to push the promise surrounding the health benefits of antioxidants into the realm of validated reality. Two key agreements emerged from the congress. First, the group agreed to assess the total phenolic compounds (believed to provide health benefits) in food using the Oxygen Radical Absorbance Capacity (ORAC) assay, as well as the Folin-Ciocalteu assay. This was a major accomplishment, as there had been little consensus in the past as to what method researchers from around the world would use in their attempts to measure the presence of phenolic compounds. Claims surrounding health benefits of antioxidants depend in part on scientists agreeing on a single workable standard which all will use to measure potential levels of compounds. For example, scientists in Great Britain may claim that blueberries have the highest level of antioxidants based on the way they measure such compounds. Meanwhile, researchers in San Francisco might claim that strawberries have the highest level, using a completely different ‘yardstick.’ The agreement to use the ORAC and Folin-Ciocalteu assays should level the playing field with respect to claims of antioxidant content within different foods. A second major obstacle confronting researchers in this field dealt with antioxidant cellular activity and absorption. While it’s important to know how foods vary in the amount of antioxidant compounds they possess, it’s more important to learn how the compounds affect cell activity, and ultimately, if any of the presumably beneficial antioxidants are absorbed in a meaningful way. To that end, the congress participants agreed on the need to quickly develop a better process for cell model screening of biological activity, and subsequent absorption. Looking to the future, the congress chairs, John Finley (A.M. Todd), and Ronald Prior (University of Arkansas), and other members of the organizing committee are considering when and where to hold the 2006 version of this event. |
