Has your wildest dream possibly come true? Has chocolate really become a health food? While we may not be quite at that point, recent research has definitely put a health-friendly face on this world-favorite treat.

Cocoa and its many chocolate derivatives are a favorite for everyone with a sweet tooth, and many people—especially women—swear that eating chocolate “just makes them feel better.” Recent research shows they may be right.

Background

The Olmec Indians of Central America first cultivated cocoa plants, sometime between 1500 and 400 bc. For centuries, consumption was confined to an unsweetened drink available only to the Mayan elite. The Spanish explorers brought that beverage to Europe, and the cocoa industry was born.1

Cocoa trees thrive in warm, moist climates near the equator. Mature trees bear thousands of tiny, waxy, five-petaled, pink or white blossoms that cluster on the trunk and older branches.

These blossoms become pods, which change from green to a gold or scarlet hue as they mature to about the size of a cantaloupe. A ripe pod yields about 50 beans, and nearly 400 are needed to make one pound of chocolate. Fat and antioxidant contents vary according to the refining process employed in the broad array of chocolate products we all enjoy today.2

Evidence of effectiveness

Although many jokes have been made about chocolate cravings, the science says the phenomenon is based on fact. For example, in one randomized study, emotional changes were measured after healthy women ate either chocolate or an apple. A control group ate nothing. Both the chocolate and the apple satisfied hunger, but the effect of the chocolate went far beyond that. Its consumption was followed by an elevated mood and increased activation not seen in the apple eaters.3

Cocoa has demonstrated benefits to cardiovascular (CV) health. A recent Dutch study assessed cocoa consumption, BP, and CV mortality by following 470 healthy elderly men (aged 65-84 years) for 15 years. Causes of death were aligned against habitual food consumption. In the entire cohort, those participants who consumed the most cocoa had the lowest BP, as well as lower CV and all-cause mortality. Researchers theorize that cocoa’s intensely concentrated flavanol antioxidants are  responsible for this effect.4

Meanwhile, a meta-analysis of placebo-controlled trials determined changes in systolic and diastolic BP associated with the intake of cocoa products. Combined results from 173 participants showed mean systolic and diastolic BP dropped 4.7 mm Hg and 2.8 mm Hg, respectively, compared with the cocoa-free controls.5

Researchers at Brigham and Women’s Hospital in Boston examined the effects of flavanol on cerebral blood flow in an effort to find a treatment for progressive cerebral ischemia. In this pilot study, 34 healthy, elderly volunteers (median age 72 years) were given either a flavanol-enriched cocoa (FRC) or a flavanol-poor cocoa (FPC). 

The enriched formula contained 451 mg of flavanols per serving, while the FPC cocoa had only 18 mg. After one week, 55% of the FRC group showed cerebral blood flow improvement of 8%, and at two weeks, blood flow was 10% better than baseline. These readings were significantly higher than those in the flavanol-poor group, where only 10% of participants attained equivalent responses.6

Other metabolic studies support the idea that the flavanols in cocoa enhance nitric oxide release, which aids in endothelial relaxation, thus promoting vasodilation to improve microvascular flow.7

Last, black tea, green tea, and red wine are also rich in antioxidants, but a head-to-head comparison concluded that cocoa’s higher flavanol content made it the beverage most “beneficial to health.”8

Safety and side effects

Allergies to chocolate are common, and because of its vasoactive nature, large quantities can cause significant drug interactions. Specifically, drugs that compete for the cytochrome P-450 enzyme metabolism pathway in the liver could be either potentiated or degraded by cocoa, resulting in ineffective or toxic levels.9

Dose

The answer to this is not as easy as you might think. While all commercial chocolate has some flavanol content, most has been put through a process called  “Dutching.”  This de-alkalinizing method makes the finished  product smoother.

According to a study cosponsored by the Hershey Company,  Dutching also reduces flavanol content by an average of 67%.10 Therefore, the less Dutching that chocolate has been subjected to, the more beneficial it will be.

Note that in some of the studies cited, participants drank four to five cups of cocoa daily. Depending on the degree of Dutching, the same effects might have been achieved with more or less hot chocolate.

Summary

The next time your patients express guilt for indulging their cocoa cravings, suggest they take a moment to read the label and choose the most natural, un-Dutched chocolate they can find.

And remember:  While the evidence of chocolate’s antioxidant qualities is clear, the fat and sugar content of commercial preparations are not necessarily healthful. Too much of anything is not good, and unleashed chocolate is no exception.

References

1. Bellis M. The culture of the cocoa bean: timeline of chocolate history.
2. World Cocoa Foundation. From the tree to the table:A cocoa bean’s journey.
3. Macht M, Dettmer D. Everyday mood and emotions after eating a chocolate bar or an apple. Appetite. 2006;46:332-336.
4. Buijsse B, Feskens EJ, Kok FJ, Kromhout D. Cocoa intake, blood pressure, and cardiovascular mortality: the Zutphen Elderly Study. Arch Intern Med. 2006;166:411-417.
5. Taubert D, Roesen R, Schömig E. Effect of cocoa and tea intake on blood pressure: a meta-analysis. Arch Intern Med. 2007;167:626-634.
6. Sorond FA, Lipsitz LA, Hollenberg NK, Fisher ND. Cerebral blood flow response to flavanol-rich cocoa in healthy elderly humans. Neuropsychiatr Dis Treat. 2008;4:433-440.
7. Cromie WJ. Cocoa shows promise as next wonder drug: boosts blood flow to heart, brain, and other organs. Harvard University Gazette. February 22, 2007.
8. Lee KW, Kim YJ, Lee HJ, Lee CY. Cocoa has more phe-nolic phytochemicals and a higher antioxidant capacity than teas and red wine. J Agric Food Chem. 2003;51:7292-7295.
9. Jellin J, Gregory P, Batz F, et al. Pharmacist’s Letter/Prescriber’s Letter Natural Medicines Comprehensive Database. 3rd ed. Stockton, Calif.: Therapeutic Research Faculty; 2000:300.
10. Miller KB, Hurst WJ, Payne MJ, et al. Impact of alkalization on the antioxidant and flavanol content of commercial cocoa powders. J Agric Food Chem. 2008;56:8527-8533.

All electronic documents accessed March 18, 2009.