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. The Latin name of the plant is Theobroma cocoa. "Theobroma" means food of the gods. Because of this, one of the stimulant substances in chocolate is named theobromine; this caffeine-related substance does not contain the element bromine.

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 have been performed.

Nonetheless, some potential benefits have been seen in preliminary trials. A controlled study of 20 males with mild hypertension compared the effects of 100 g daily of a flavonol-rich dark chocolate as compared to a flavonol-free white chocolate. ¹ Results appeared to indicate that the dark chocolate produced improvements in blood pressure. A subsequent study of similar design, this one enrolling 44 people with mild hypertension, found that a much lower dose of dark chocolate (6.3 g daily), also significantly reduced blood pressure levels. ² And, a review including several additional studies drew the same conclusion regarding chocolate’s modest yet favorable effect on blood pressure. ³ Chocolate has also shown some promise for improving cholesterol profile . In one study, 57 people with high cholesterol were given either a standard snack bar or a snack bar enriched with cocoa flavanols. ⁴ Over 6 weeks, the results appeared to indicate that cocoa improved cholesterol levels to a greater extent than placebo. Two other preliminary studies found evidence that consumption of chocolate can improve levels of HDL (“good”) cholesterol. ⁵ One double-blind study failed to find that flavanol-rich cocoa improved blood vessel health in people with established cardiovascular disease. ⁶ Besides flavonols, chocolate contains a fat called stearic acid. Although it is a saturated fat, stearic acid is hypothesized to have cardiovascular-preventive benefits. However, this is not yet proven. ⁷ Like other antioxidants, consumption of high flavonol cocoa might also offer some protection to the skin from UV damage. ⁸ 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 to standard sunblock.

An unpublished double-blind study (available only in the form of a press release) reportedly found that dark chocolate is helpful for chronic fatigue syndrome. ⁹ The theobromine in cocoa, besides being a stimulant, might also have a cough-suppressant effect. ¹⁰

In studies, the typical daily dose of flavanols from chocolate thought to offer a beneficial effect range widely from 30 to 500 mg per day.

The flavanol content of chocolate itself also varies widely. White chocolate contains little to no flavanols, commercial dark chocolate can contain as much as 500-2,000 mg of flavonols per 100 grams of chocolate. Special flavonol-enriched forms of chocolate are also available.

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