Sweet relief: Guilty pleasure could have health benefits

Studies of chocolate's naturally high flavanol content are revealing some intriguing findings about the advantage of this much-loved confection.

By Susan J. Landers — Posted Dec. 6, 2004

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Chocolate is more than a food -- it's often a way straight to someone's heart. That's why great quantities of this most delectable candy will be given as gifts this holiday season and throughout the year.

But could this velvety concoction also have a second heartfelt value -- playing a role in a heart-healthy diet? That's a question now gaining currency.

Of course, this is not the first time such an idea has been considered a possibility.

Even in the ancient Americas, the products of the Theobroma cacao tree were thought to possess amazing health properties. Its flowers and beans were valued as aphrodisiacs and treatments for indigestion, kidney disease, exhaustion, wasting or thinness, hypochondria and hemorrhoids by the Olmec, Maya and Aztec peoples of South and Central America. Many of these uses spread to Europe.

But chocolate's star as a health food dimmed over the centuries, and it eventually assumed its current place as a guilty indulgence -- as well it should. For, alas, there is little health benefit that can be attributed to the typical chocolate bar snatched up while waiting in the checkout line of your neighborhood supermarket or the tidbit carefully selected from among its companions nestled in a large heart-shaped box.

New studies, however, are again associating this sweet treat with some surprisingly medicinal attributes.

"Since remote antiquity, there has been a dual aspect to chocolate: chocolate as food; chocolate as medicine," notes Louis E. Grivetti, PhD, professor of nutrition at the University of California, Davis. Dr. Grivetti has studied chocolate's role in history.

"It is clear that during the past five to six years, the positive health effects of eating certain types or kinds of chocolate, specifically chocolates where the phytochemicals are not destroyed during production, are similar to drinking red wine and/or taking a baby aspirin in regard to having a positive impact on platelet aggregation and clotting time," he said.

Research findings are demonstrating that cocoa beans processed in a way that retains their naturally high flavanol content, could, indeed, play a role in a heart-healthy diet -- and that is good news for chocolate lovers. The flavanol level of chocolate and cocoa can be much higher than levels found in black tea and red wine, which have received a fair amount of attention in recent years for their roles in promoting good heart health.

But hold on. "Don't go out and eat a lot of chocolate," cautions Naomi Fisher, MD, director of hypertension services at Brigham and Women's Hospital in Boston, who has researched the health benefits of chocolate. "The primary ingredients are sugar and fat, so it is not at all a health food." At least not yet.

Still, there is hope. As a lover of dark chocolate, Dr. Fisher happily reports that chocolate could someday be a health food. "What I think will happen and what is happening already is that companies will be devising products that can taste good and be good for you. ... I think there is a general feeling that this is the future, and it is so delicious. Such a tasty concept."

An "ah-ha!" moment

Dr. Fisher came to her chocolate research in a roundabout way that also makes a lot of sense. It tracked with the realization of the need to improve the dismal state of the world's cardiovascular health as well as the growing understanding of the role genes play.

Dr. Fisher, along with Norman K. Hollenberg, MD, PhD, professor of medicine at Harvard Medical School in Boston, studied a population of Kuna Indians who lived on an island off the coast of Panama to determine how they came by their enviably low rates of hypertension. Unlike most of the rest of the world's people, there seemed to be no increase in blood pressure as the Kuna aged.

The researchers' first hypothesis was that salt, or the lack thereof, in the Kuna diet was the factor that made all the difference. "But the people on the island ate a lot of sodium, so the first hypothesis was disproved rather quickly," Dr. Fisher said. The thought that protective genes were at work also was discounted when researchers found that the Kuna who moved to the mainland were no longer protected from hypertension.

But an examination of the islanders' diet revealed that they drank large quantities of lightly processed cocoa that presumably retained a high level of flavanols.

"The island-dwelling Kuna drink five cups of cocoa a day, as a minimum, and often much more," Dr. Hollenberg explained at a day-long symposium, "Theobroma cacao: Ancient Crop, Medicinal Plant, Surprising Future," held last February at the National Academies in Washington, D.C.

Those who drank substantial amounts of cocoa had high levels of nitric oxide, which is important for opening up blood vessels and increasing blood flow. The effect was not seen among Kuna who moved to the mainland and drank little or no cocoa, Dr. Hollenberg said.

Back in Boston, Dr. Fisher, Dr. Hollenberg and colleagues found that flavanol-rich cocoa also induced nitric-oxide-dependent vasodilation in the 27 healthy subjects studied. This insight, the researchers concluded, could explain the cardiovascular benefits of flavanols. Their research was published in the December 2003 Journal of Hypertension.

Other studies back the claim that flavanols reduce platelet stickiness in the blood and help prevent lethal clots. Flavanols also are thought to be antioxidants that help reduce the oxidation of LDL cholesterol.

Researchers at the University of California, San Francisco, found improvements in endothelial function among the volunteers they studied who ate high-flavanol chocolate compared with those who ate a low-flavanol chocolate. That research was published in the June issue of the Journal of the American College of Nutrition.

Of course, locating flavanol-rich chocolate both to use in research and to eat for health's sake could be difficult, because flavanol levels aren't labeled on conventional chocolate and cocoa products. But candy manufacturer Mars provides research funds and a supply of cocoa powder they make specifically to have high flavanol levels.

A funding stream

Mars, whose existence is tied closely to cocoa, has funded and published nearly 100 studies, including those mentioned above, on the science and health attributes of chocolate, said Harold Schmitz, PhD, director of Science and External Research at the family-owned business.

Not being a company that must "bow to the quarterly earning statement," Mars is free to devote a lot of money to research, which is not necessarily a profit-earning enterprise, Dr. Schmitz said.

But Mars was inspired to develop such an agenda after seeing Brazil's entire cocoa crop fall victim to disease. The vulnerability of the crop, which is grown primarily on small farms in tropical areas that can be volatile both politically and climactically, also provided a research incentive. "As we started to understand the chemistry of cocoa from a plant science and disease resistance perspective, we then got interested in studying the chemistry from a flavor perspective," he said.

From flavor, it was a short hop to flavanols and their ability to protect against cardiovascular disease. "So then we thought, not only is the biology interesting, but it could be relevant from the public health perspective."

Even though there was not an immediate return on the money spent for research, Mars stands to make gains in the health arena if chocolate takes off as a healthy food, although Dr. Schmitz is quick to say that much more research is necessary before any such claim can be made.

Meanwhile, Mars has been marketing a snack bar called CocoaVia on the Internet. CocoaVia combines high levels of flavanols and plant sterol extracts. Research demonstrating that eating two CocoaVia bars a day could reduce cholesterol levels was presented at the American Heart Assn.'s scientific conference Nov. 8.

Dr. Schmitz said he always has eaten chocolate, but it was accompanied by a certain amount of guilt. Now that the research findings are positive, "My chocolate consumption didn't change, but I started feeling a lot better about eating it."

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Chocolate as medicine through the ages

  • Mayan healers chanted to cure skin eruptions, fevers and seizures. When chanting ended, a bowl of chacah or medicinal chocolate (cacao blended with honey, pepper, and tobacco juice) was drunk by the patients. -- Ritual of the Bacabs, Ralph Roys, University of Oklahoma Press, 1965
  • From time to time the men of Montezuma's guard brought him, in cups of pure gold, a drink made from the cacao plant, which they said he took before visiting his wives. -- Bernal Diaz del Castillo, 1560
  • When an ordinary amount of cacao is drunk, it gladdens, refreshes, consoles and invigorates. Thus it is said: I take cacao. I wet my lips. I refresh myself. -- Codex Florentine, Friar Bernardino de Sahagun, 1590
  • Chocolate preserves the countenance fresh and fair: it strengthens the vitals and is good against fever, asthma and consumption of all sorts. -- William Hughes, 1672
  • Use chocolate to cure: Wasting or thinness brought on by lung and muscle disease; hypochondria; hemorrhoids. -- Carl Linnaeus, 1741

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External links

The Chocolate Information Center, supported by Mars Inc. (link)

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