Most people love chocolate, and numerous psychoactive chemicals have been found in it that may explain its attraction. These include caffeine (a stimulant), theobromine (structurally similar to caffeine), serotonin (a neurotransmitter with mood-elevating effects) and phenylethylamine (a natural amphetamine-like compound). Moreover, chocolate was recently found to contain anandamide. This substance, which occurs naturally in the brain, binds to cannabinoid receptors and mimics the effects of cannabinoid drugs such as marijuana. [1] At issue is whether the level of these constituents is adequate to explain chocolate's special attraction. [2]

Could chocolate have health benefits besides its effect on mood? Let's review some of the data:

Positives

Chocolate is quite nutritious. Not only is it a good source of folic acid, [3] copper, [4] and magnesium, [5] but it is rich in antioxidant polyphenols, [6] including flavonoids. [7] The polyphenol content alone in a single 40 gram candy bar of dark chocolate is equivalent to 2 days' worth of fruits and vegetables. [8] In fact, cocoa powder is believed to surpass both green tea and garlic as a protective antioxidant food. [9]

Monomers of the flavonoid catechin in commercial dark chocolate are 4 times higher than those in black tea, and epidemiological studies suggest that tea, presumably because of these monomers, may have a protective effect against cardiovascular diseases, and possibly cancer. 7 This comparison is even more striking when the catechin oligomers are included, as they are abundant in chocolate, but are present in only minor amounts in tea. [10] These substances resemble the oligomeric proanthocyanidins found in Pycnogenol[R], a commercial antioxidant extract which has been studied extensively for its beneficial health effects. [11]

Chocolate's flavonoids are generally more powerful than vitamins in limiting the oxidation of cholesterol circulating in low-density, and very-low-density lipoproteins (LDL & VLDL cholesterol), [9] a process which has been found to be fundamental to the development of atherosclerosis. Indeed, when volunteers consumed cocoa in which the fat had been removed, the time it took for LDL to oxidize (lag time) was prolonged. [12] There is also evidence that cocoa has an aspirin-like effect on blood clotting. [13]

Negatives

Chocolate is high in fat, the majority of which is saturated, and cocoa butter has been shown to raise serum cholesterol concentrations. [14] Thirty percent of the fatty acids in chocolate consist of stearic acid, a long-chain saturated fatty acid. A study of 80,000 women found that stearic acid increased the risk of coronary heart disease (CHD) more than the other three long-chain saturates (lauric, myristic and palmitic acids). [15] The data also suggested, however, that moderate chocolate consumption is unlikely to have major adverse or beneficial effects on CHD risk. [16]

Rich in oxalates, chocolate may contribute to the development of kidney stones. [17] Its high content of methylxanthines (theobromine and caffeine) may foster the development of benign breast disease [18] and migraine headaches. [19] Chocolate ingestion relaxes the lower esophageal sphincter, [20] which may cause heartburn.

In addition, there have been numerous reports of hypersensitivity reactions to chocolate, resulting in headache, eczema, bronchial asthma and other illnesses. [21] However, some of these reactions can be attributed to its additives, such as soya lecithin, vanillin, and lactose.

Discussion

Excitement over the presence of polyphenolic compounds in chocolate must be tempered for now, as little is yet known about the physiological effects of the complex mixtures of these substances found in fruits and vegetables. [22] Also, in commercial chocolate, so much sugar is added to the chocolate liquor produced from the cocoa bean that it accounts for about half of its composition -- and thus is certain to reduce its potential health benefits. In addition, some manufacturing techniques eliminate the flavonoids. [23]

While the final verdict is not in, there seems to be little reason to avoid enjoying a little chocolate. Who knows, it may even be good for you!

Doctor Werbach cautions that the nutritional treatment of illness should be supervised by physicians or practitioners whose training prepares them to recognize serious illness and to integrate nutritional interventions safely into the treatment plan.

References

(1.) di Tomaso E et at. Brain cannabinoids in chocolate. Nature 382:877-8, 1996

(2.) Benton 0, Donohoe RT. The effects of nutrients on mood. Public Health Nutr 2(3A):403-9, 1999

(3.) Anonymous. Government sets folate standard to prevent birth defects. Nutrition Week 22(37):2-3, 1992

(4.) Joo S-J, Betts NM. copper intakes and consumption patterns of chocolate foods as sources of copper for individuals in the 1987-88 Nationwide Food consumption Survey. Nutr Res 16(1):41-9, 1995

(5.) Planells E el at. Ability of a cocoa product to correct chronic Mg deficiency in rats. Int J Vitam Nutr Res 69(1):52-60, 1999

(6.) Zumbe A. Polyphenols in cocoa: are there health benefits? BNF Nutr Bull 23:94-101, 1998

(7.) Arts Ilja CW et al. Chocolate as a source of tea flavonoids. Research letter. Lancet 354:488, 1999

(8.) Anonymous. Cheers for chocolate. Science vol. 284, April 2, 1999

(9.) Vinson JA et at. Phenol antioxidant quantity and quality in foods: cocoa, dark chocolate, and milk chocolate. J Agri Food Chem 47(12):4821-4, 1999

(10.) Lazarus SH et al. Chocolate contains additional flavonoids not found in tea. Letter. Lancet 354:1825, 1999

(11.) Kilham C. Coffee and chocolate, the new health foods. HerbalGram 47:21, 1999

(12.) Kondo K et at. Inhibition of LDL oxidation by cocoa. Letter. Lancet 348:1514, 1996

(13.) Rein D et at. Cocoa inhibits platelet activation and function. Am J Clin Nutr 72:30-5, 2000

(14.) Connor WE et at. The cholesterol balance and fecal neutral steroid and bile acid excretion in normal men fed dietary fats of different fatty acid composition. J Clin Invest 48:1363-75, 1969

(15.) Hu FB et al. Dietary saturated fats and their food sources in relation to the risk of coronary heart disease in women. Am J Clin Nutr 70:1001-8, 1999

(16.) Hu FB et al. Reply to PM Kris-Etherton et al. Letter. Am J Clin Nutr 72:1059-60, 2000

(17.) Nguyen NU et at. Increase in calciuria and oxaluria after a single chocolate bar load. Horm Metab Res 26(8):383-6, 1994

(18.) Bullough B et al. Methylxanthines and fibrocystic breast disease: a study of correlstions. Nurse Pract 15(3):36-8, 43-4, 1990

(19.) Schweitzer JW et al. Chocolate, beta-phenylethylamine and migraine re-examined. Nature 257:256, 1975

(20.) Babka JC, Castell DO. On the genesis of heartburn. The effects of specific foods on the lower esophageal sphincter. Am J Dig Dis 18(5):391-7, 1973

(21.) Werbach MR. Werbach's Nutritional Influences on Illness CD-ROM. Los Angeles, Third Line Press, 1998

(22.) Ryan MA. Chocolate: new facts come to light. Today's Chemist at Work (ACS), July, 1999

(23.) Raloff J. chocolate Hearts. Yummy and good medicine? Science News 157(12), March 18, 2000

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