What are the health benefits of chocolate?

Overview

Made from the beans of the cocoa tree, chocolate was first developed as a food
in South America, where it was primarily consumed as a bitter beverage. Cocoa was
not combined with sugar until the Spaniards brought chocolate
back to Europe from the Americas. The Latin name of the cocoa tree is
Theobroma cacao (theobroma means “food of the
gods”), and because of this, one of the stimulant substances in chocolate is named
theobromine. This caffeine-related substance, however, does not contain the
element bromine.

Possible Health Benefits

Chocolate is rich in antioxidants in the flavonol family,
substances similar to those found in green tea, red wine, grapes, soy, and other
potentially healthful foods. However, this alone is not enough to prove that
chocolate provides any health benefits. In gigantic studies of other strong
antioxidants, such as vitamin E, none of the hoped-for
benefits materialized. Only double-blind, placebo-controlled studies can prove a
treatment effective, and for chocolate, few of these studies have been
performed.

Nonetheless, some potential benefits have been seen in preliminary trials. A
controlled study of twenty males with mild hypertension
compared the effects of 100 grams (g) daily of a flavonol-rich dark chocolate
compared with a flavonol-free white chocolate. Results appeared to indicate that
the dark chocolate produced improvements in blood
pressure. A subsequent study of similar design, this one
enrolling forty-four people with mild hypertension, found that a much lower dose
of dark chocolate (6.3 g daily), also significantly reduced blood pressure levels.
Also, a review including several additional studies drew the same conclusion
regarding chocolate’s modest yet favorable effect on blood pressure.

Chocolate has also shown some promise for improving cholesterol profile. In one
study, fifty-seven people with high cholesterol were given either a standard snack
bar or a snack bar enriched with cocoa flavonols. In six weeks, the results
appeared to indicate that cocoa improved cholesterol levels to a
greater extent than placebo. Two other preliminary studies found evidence that the
consumption of chocolate can improve levels of HDL (good) cholesterol.

One double-blind study failed to find that flavonol-rich cocoa improved blood vessel health in people with established cardiovascular disease. Besides flavonols, chocolate contains a fat called stearic acid. Although it is a saturated fat, stearic acid is hypothesized to improve cardiovascular health. However, this has not been proven.

Like other antioxidants, the consumption of high- flavonol cocoa might also offer some protection to the skin from ultraviolet damage. This could, in theory, help prevent sunburn, reduce symptoms of photosensitivity, and help prevent age-related skin changes. However, the benefits would be small compared with standard sun block.

An unpublished double-blind study reportedly found that dark chocolate is
helpful for chronic fatigue syndrome. The theobromine in cocoa, in
addition to being a stimulant, might also have a cough-suppressant effect.

Dosage

In studies, the typical daily dose of flavonols from chocolate thought to offer a beneficial effect range widely from 30 to 500 milligrams (mg) per day. The flavonol content of chocolate itself also varies widely. White chocolate contains little to no flavonols, and commercial dark chocolate can contain as much as 500 to 2,000 mg of flavonols per 100 g of chocolate. Special flavonol-enriched forms of chocolate are also available.

Safety Issues

As a widely consumed food, chocolate is assumed to have a high safety factor.
However, because of its caffeine and theobromine content, it
would be expected to have potential side effects similar to those of coffee and
black tea, namely heartburn, gastritis, insomnia, anxiety, and heart arrhythmia
(benign palpitations or more serious disturbances of heart rhythm). All drug
interactions that can occur with caffeine would be expected to occur with
chocolate. Also, most chocolate products are high in calories and therefore could
lead to weight gain.

Important Interactions

Persons taking monoamine oxidase inhibitors should note that the caffeine
in chocolate could cause dangerous drug interactions. Stimulant drugs such as
ritalin might amplify the stimulant effects of chocolate.
Chocolate also might interfere with drugs that prevent heart arrhythmias
or with drugs that treat insomnia, heartburn, ulcers, or anxiety.

Bibliography

Baba, S., et al. “Plasma LDL and HDL Cholesterol and Oxidized LDL Concentrations Are Altered in Normo- and Hypercholesterolemic Humans After Intake of Different Levels of Cocoa Powder.” Journal of Nutrition 137 (2007): 1436-1441.

Heinrich, U., et al. “Long-Term Ingestion of High Flavanol Cocoa Provides Photoprotection Against UV-Induced Erythema and Improves Skin Condition in Women.” Journal of Nutrition 136 (2006): 1565-1569.

Hooper, L., et al. “Flavonoids, Flavonoid-Rich Foods, and Cardiovascular Risk.” American Journal of Clinical Nutrition 88 (2008): 38-50.

Ried, K., et al. “Does Chocolate Reduce Blood Pressure?” BMC Medicine 8 (2010): 39.

Rusconi, M., and A. Conti. “Theobroma cacao L., the Food of the Gods: A Scientific Approach Beyond Myths and Claims.” Pharmacological Research 61 (2010): 5-13.

Taubert, D., et al. “Effects of Low Habitual Cocoa Intake on Blood Pressure and Bioactive Nitric Oxide.” Journal of the American Medical Association 298 (2007): 49-60.