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Valentine’s Sweetest Treat

Dark Chocolate's Cancer Prevention Powers

Focused on Health - February 2009

By Rachel Winters

"The great news this Valentine’s Day is that in addition to being decadent and delicious, moderate amounts of dark chocolate may play a role in cancer prevention,” says Sally Scroggs, M.S., R.D., L.D., health education manager in M. D. Anderson’s Cancer Prevention Center.

Recent research shows that dark chocolate has chemicals, called flavonoids, which have been shown to play a role in reducing cancer risks. Flavanoids act as antioxidants and occur naturally in the plant-based cacao bean, the base of all chocolate products. Cacao beans are, in fact, one of the most concentrated natural sources of antioxidants that exist. Cacao beans are roasted, ground and processed to make a variety of different chocolate products. Processing the cacao bean can change the percentage of cacao left in the final chocolate product.

“Dark chocolate has more of these healthy antioxidants, without the increased sugar and saturated fats that are added to milk chocolate,” Scroggs says.

Chocolate has been a favorite food for centuries, according to the American Dietetic Association. It has become a symbol for love, indulgence, temptation and now, we can justify it for its health attributes.

“Now you can eat chocolate without feeling as guilty,” Scroggs says. “And that is something everyone can feel good about.”

Antioxidant’s Role in Cancer Prevention

“Antioxidants play a role in cancer prevention by protecting cells from free radicals,” Scroggs says. “Free radicals can make a cell unstable, so as a damaged cell multiplies, it has the potential to grow into a tumor. Antioxidants help keep the cells balanced and prevent tumor growth.”

One way to enhance the body’s antioxidant defenses is to eat antioxidant-rich foods, such as dark chocolate. Other well-known foods that contain antioxidants include blueberries, walnuts, cranberries, teas (green and black) and red wines. Antioxidant levels are determined by Oxygen Radical Absorbance Capacity, which measures a food’s ability to neutralize the harmful effects of free radicals. Data from the U.S. Department of Agriculture and the Journal of the American Chemical Society indicates that dark chocolate tops the list for Oxygen Radical Absorbance Capacity on a per serving basis

Darker Chocolate Packs a Punch

The Oxygen Radical Absorbance Capacity lists only dark chocolate, as opposed to milk or white chocolate, as being an antioxidant superpower.

“The main reason that eating dark chocolate, versus milk or white chocolate, reduces cancer risks is because it has a higher percentage of cacao, and thus antioxidants,” Scroggs says.

As the cacao content goes up, there’s also less room for sugar. According to the American Institute for Cancer Research, people should aim for plain chocolate that contains at least 65% cacao, as opposed to the kind of chocolate commonly used in cakes and cookies, which contain more calories, sugar and unhealthy fats.

When eating chocolate, looking at portion size and calorie content also is crucial. Recommended servings for dark chocolate are seven ounces per week, which is about one ounce per day.

“Savoring a small amount of dark chocolate is much better than gulping soft drinks or eating doughnuts,” Scroggs says. “Remember, dark chocolate is still a calorie-dense food that can be high in fat. You can enjoy it daily as part of a balanced diet, as long as you keep your portion size in check.”

Dark Chocolate Gift Guide

This Valentine’s Day, pick out a box of dark chocolate to show someone how much you care! “Chocolate is certainly one of my favorite Valentine’s Day gifts,” Scroggs says.

Here are some tips for buying a gift that is good for the heart in more ways than one:

  1. Choose dark chocolate with a high cacao percentage(65% or higher).
  2. Buy chocolate that can be eaten in small portions, such as individually wrapped chocolates or boxed candy (approximately 1 oz per serving).
  3. Check the ingredients.Make sure they don’t contain fats, such as palm and coconut oils, and that they are made without the use of ‘hydrogenated’ or ‘partially hydrogenated’ oils.
  4. Include a special message in a Valentine’s Day card.Remind the person you love that dark chocolate can aid in cancer prevention. Because it’s only healthful in small portions, also encourage him or her to share the chocolates with others.
  5. Give cocoa powder – it also makes a great gift.In addition to dark chocolate candies, gourmet cocoa powder, used for hot chocolate and baking, also comes in 65% cacao versions.
  6. Make your Valentine’s Day shopping easy and funby looking-up the nutrition information and portion sizes of your favorite brands before hitting the stores. Most companies now list everything online.

Defining Chocolate

  • Cacao
    Used in FDA regulations to refer to the bean, which is the source of the cacao components chocolate liquor, cocoa butter and cocoa powder
  • Milk Chocolate
    A combination of chocolate liquor (not alcohol), cocoa butter, sugar and milk or cream. Milk chocolate must contain at least 10% chocolate liquor and at least 12% total milk ingredients.
  • Sweet Chocolate
    A combination of chocolate liquor, cocoa butter and sugar, but contains at least 15% chocolate liquor.
  • Semisweet or Bittersweet Chocolate
    A combination of chocolate liquor, cocoa butter and sugar, but contains at least 35% chocolate liquor. Sweet chocolate and semisweet chocolate often are called dark chocolate.
  • Chocolate, Unsweetened Chocolate or Baking Chocolate
    Chocolate or chocolate liquor is produced by grinding cacao beans smooth into a liquid state. This chocolate can be sold as unsweetened chocolate or baking chocolate or used to make other chocolate types such as milk chocolate, sweet chocolate or semisweet chocolate.
  • White Chocolate
    Made from the same ingredients as milk chocolate (cocoa butter, milk, sugar) but without the nonfat cocoa solids. In 2002, FDA established a standard of identity for white chocolate. White chocolate must contain at least 20% cocoa butter and 14% total milk ingredients.
  • Cocoa
    Cocoa is the product made by removing part of the fat (cocoa butter) from the cacao beans and grinding the remaining material minus the shell.

Source: United States Food and Drug Administration

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© 2014 The University of Texas MD Anderson Cancer Center