Chocolate: Even Healthier Than You Knew

by Carole Jackson, Bottom Line Health

One of my coworkers has a secret stash in her bottom desk drawer. Where the characters in Mad Men keep bottles of Scotch, she hoards piles of chocolate bars, truffles and kisses that would make Willy Wonka envious. As we all happily know by now, numerous studies vindicate my friend’s sweet tooth — trial after trial confirms that healthful components in chocolate and cocoa can be helpful for everything from heart disease to brain function (assuming that we don’t overindulge, of course).

So, here’s the latest good news for my coworker and all you chocoholics — now researchers are finding that chocolate can help sharpen your eyes… and even cure a cough!

Sharpen Your Eyes and Mind

In a small study at the University of Reading in the UK reported in the June 2011 issue of Physiology & Behavior, dark chocolate beat white chocolate (used as a control) in tests of vision and memory and reaction time tasks. Researchers had 30 volunteers aged 18 to 25 consume two different candy bars — a 35-gram (about 1.25 ounces) commercially available dark chocolate bar containing 773 milligrams of cocoa flavonols and a 35-gram white chocolate bar with no flavonols on separate occasions one week apart. Afterward, investigators tested volunteers on tasks measuring vision, memory and reaction time.

When the volunteers ate the dark chocolate they experienced 17% enhanced visual sensitivity (the ability to see in difficult conditions) for up to two-and-one-half hours, as compared with when they ate the white chocolate.

In cognitive tests, compared with white chocolate, dark chocolate stepped up participants’ memory and reaction times — they were able to correctly identify more of a number of objects that had been switched from their original places.

Researchers speculate that cocoa flavonols achieve these effects by increasing blood and oxygen flow. Since the enhanced performance was just among those who ate dark chocolate and not white chocolate, researchers can rule out the “sugar buzz” as being the reason for improved performance.

Chocolate: The New Cough Medicine

What else can chocolate do for us? Produce a more effective cough medicine? Why not, say scientists at Imperial College London, who determined that theobromine — a key ingredient in chocolate — was one-third more successful in quieting coughs than the powerful narcotic codeine.

About the research: On three different occasions, investigators gave 10 healthy volunteers theobromine, codeine or a placebo. Next they exposed them to capsaicin, the spicy compound in red pepper that can make some people cough. Higher amounts of capsaicin (about one-third more) were required to produce coughs in the theobromine group, and theobromine proved more effective than a typical dose of codeine as a cough suppressant.

Theobromine directly affects the vagus nerve, which is responsible for coughs, and unlike codeine it does not cause drowsiness. Codeine is an opiate — so a cocoa-based cough remedy would be much safer for anyone driving, using machinery and so on. A theobromine-based drug is in clinical trials in the UK.

Satisfy Your Sweet Tooth… But in Moderation, Please!

Alice H. Lichtenstein, DSc, a professor of nutrition science and policy at Tufts University’s Friedman School of Nutrition, finds chocolate research intriguing and believes it warrants further investigation. She says that if you enjoy chocolate, go ahead and eat it in moderation — but it should not be your only rich source of flavonols.

Dr. Lichtenstein’s recommendation: Every day, consume a wide range of flavonol-rich foods and beverages, such as blueberries, cranberries, pomegranates, grapes, grape juice, red wine, green tea… and if you like, a little chocolate.


Alice H. Lichtenstein, DSc, Stanley N. Gershoff Professor of Nutrition Science and Policy, Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy, director and senior scientist, Cardiovascular Nutrition Laboratory, Jean Mayer USDA Human Nutrition Center on Aging Professor of Medicine, Tufts University School of Medicine, Boston.