Health effects of chocolate

While chocolate is regularly eaten for pleasure, there are potential beneficial health effects of eating it. Cocoa or dark chocolate benefits the circulatory system. Other beneficial effects suggested include anticancer, brain stimulator, cough preventer, reduced risk of heart disease and antidiarrhoeal effects. That chocolate has an aphrodisiac effect is yet to be a well supported claim.

On the other hand, the unconstrained consumption of large quantities of any energy-rich food, such as chocolate, without a corresponding increase in activity increases the risk of obesity . Raw chocolate is high in cocoa butter, a fat which is removed during chocolate refining, then added back in at varying proportions during the manufacturing process. Manufacturers may add other fats, sugars, and milk as well, all of which increase the caloric content of chocolate.

Chocolate absorbs lead from the environment during production and there is concern of mild lead poisoning for some types of chocolate. Additionally, chocolate is toxic to many animals because of insufficient capacity to metabolize theobromine.

A study reported by the BBC indicated that melting chocolate in one's mouth produced an increase in brain activity and heart rate that was more intense than that associated with passionate kissing, and also lasted four times as long after the activity had ended. Cocoa products also contain pharmacological substances such as n-arclethanolamines that are related to cannabis.^{[citation needed]} When drugs are used to block the brain's opiate receptors,the desire for chocolate disappears, confirming the addictive nature of these types of foods.^{[citation needed]}

Migraines

Research on rats has determined that increased chocolate intake enhances the expression of MKP in the trigeminal ganglion, lowering the level of CGRP and other inflammatory chemicals, suppressing the symptoms of migraines.

Circulatory benefits

Recent studies have suggested that cocoa or dark chocolate may possess certain beneficial effects on human health. This is mainly caused by a particular substance present in cocoa called epicatechin. Cocoa possesses a significant antioxidant action, protecting against LDL oxidation, perhaps more than other polyphenol antioxidant-rich foods and beverages. Chocolate phenols have been shown to protect the arteries from plaque formation and to prevent LDL oxidation for two hours after consumption. Some studies have also observed a modest reduction in blood pressure and flow-mediated dilation after consuming dark chocolate daily. Consuming milk chocolate or white chocolate, or drinking fat-containing milk with dark chocolate, appears to largely negate the health benefit. Processed cocoa powder (Dutch process chocolate), processed with alkali, greatly reduces the antioxidant capacity as compared to "raw" cocoa powder.

One-third of the fat in chocolate comes from the monounsaturated fat oleic acid, another one-third from the saturated fat stearic acid, and another one-third from the saturated fat palmitic acid. However, unlike other saturated fats, stearic acid does not raise levels of LDL cholesterol in the bloodstream and has neutral effects on cholesterol. Stearic acid can be converted to oleic acid in the liver. Consuming relatively large amounts of dark chocolate and cocoa does not seem to raise serum LDL cholesterol levels; some studies even find that it could lower them. Indeed, small but regular amounts of dark chocolate have been associated with a lower risk of a heart attack.

In addition, Mursu et al., performed a study in which long term consumption of chocolate, in groups that were receiving chocolate that contained cocoa mass, led to an increase of HDL cholesterol by 11%. In that same study there was a group that was eating dark chocolate that had been enriched with cocoa polyphenols and they experienced an increase of their HDL cholesterol by 14%.

A study performed at the Karolinska Institute in Stockholm and appearing the Journal of Internal Medicine (September 2009), found that survivors of heart attacks who ate chocolate at least two or three times a week reduced their risk of death by a factor of up to three times compared to survivors who did not eat chocolate. The benefits were specific to chocolate and not to other sweets.

Aphrodisiac

Romantic lore commonly identifies chocolate as an aphrodisiac. The reputed aphrodisiac qualities of chocolate are most often associated with the simple sensual pleasure of its consumption. Although there is no proof that chocolate is indeed an aphrodisiac, a gift of chocolate is a familiar courtship ritual. Research looking at the psychoactivity of chocolate reveals that methylxanthine, an active biological substance found in chocolate, competes with adenosine, a presynaptic inhibitor modulator, and blocks its receptor. This induced blockage can lead to arousal. The participants' blood pressure decreased, and they showed improvements in insulin sensitivity, meaning they were better able to metabolize glucose.

Muscle recovery

A study from James Madison University, presented at the American College of Sports Medicine annual meeting, showed that post-exercise consumption of lowfat chocolate milk provides equal or possibly superior muscle recovery compared to a high-carbohydrate recovery beverage with the same amount of calories. Athletes consuming chocolate milk had significantly lower levels of creatine kinase, an indicator of muscle damage, compared to drinkers of carbohydrate beverage. Sweating causes loss of fluid and also important minerals, including calcium, potassium and magnesium. The 2-hour window after exercise is an important, but often neglected opportunity to recover. This study has frequently been criticized, however, as it was sponsored by the dairy industry and included a very small sample size.

Other benefits

Studies suggest a specially formulated type of cocoa may be nootropic and delay brain function decline as people age.

Mars, Incorporated, a Virginia-based candy company, spends money each year on flavonol research. The company is talking with pharmaceutical companies to license drugs based on synthesized cocoa flavonol molecules. According to Mars-funded researchers at Harvard, the University of California, and European universities, cocoa-based prescription drugs could potentially help treat diabetes, dementia and other diseases.

As a cough suppressant, theobromine was found to be almost one third more effective than codeine, the leading cough medicine.

Flavonoids can inhibit the development of diarrhea, suggesting antidiarrhoeal effects of cocoa.

Obesity risk

The major concern that nutritionists have is that even though eating dark chocolate may not affect serum cholesterol, blood pressure or LDL oxidation, it is not known whether it affects certain biomarkers of cardiovascular disease. Furthermore, the amount needed to have this effect would provide a relatively large quantity of calories, which, if unused, would promote weight gain. Obesity is a significant risk factor for many diseases, including cardiovascular disease. As a consequence, consuming large quantities of dark chocolate in an attempt to protect against cardiovascular disease has been described as 'cutting off one's nose to spite one's face'.

Acne

Chocolate, ranging from dark to light, can be molded and decorated like these chickens with ribbons

There is a popular belief that the consumption of chocolate can cause acne. This belief is not supported by scientific studies. Various studies point not to chocolate, but to the high glycemic nature of certain foods, like sugar, corn syrup, and other simple carbohydrates, as a cause of acne. Chocolate itself has a low glycemic index. Other dietary causes of acne cannot be excluded yet, but more rigorous research is suggested.

Lead

Chocolate has one of the higher concentrations of lead among products that constitute a typical Westerner's diet, with a potential to cause mild lead poisoning. Recent studies have shown that although the beans themselves absorb little lead, it tends to bind to cocoa shells and contamination may occur during the manufacturing process. A recent peer-reviewed publication found significant amounts of lead in chocolate. In a USDA study in 2004, mean lead levels in the samples tested ranged from 0.0010 to 0.0965 µg lead per gram of chocolate, but another study by a Swiss research group in 2002 found that some chocolate contained up to 0.769 µg per gram, close to the international (voluntary) standard limit for lead in cocoa powder or beans, which is 1 µg of lead per gram. In 2006, the U.S. FDA lowered by one-fifth the amount of lead permissible in candy, but compliance is only voluntary. While studies show that the lead consumed in chocolate may not all be absorbed by the human body, there is no known threshold for the effects of lead on children's brain function and even small quantities of lead can cause permanent neurodevelopmental deficits including impaired IQ.

Toxicity in animals

Main article: Theobromine poisoning

In sufficient amounts, the theobromine found in chocolate is toxic to animals such as horses, dogs, parrots, small rodents, and cats because they are unable to metabolise the chemical effectively. If they are fed chocolate, the theobromine will remain in their bloodstream for up to 20 hours, and these animals may experience epileptic seizures, heart attacks, internal bleeding, and eventually death. Medical treatment performed by a veterinarian involves inducing vomiting within two hours of ingestion and administration of benzodiazepines or barbiturates for seizures, antiarrhythmics for heart arrhythmias, and fluid diuresis.

A typical 20-kilogram (44 lb) dog will normally experience great intestinal distress after eating less than 240 grams (8.5 oz) of dark chocolate, but will not necessarily experience bradycardia or tachycardia unless it eats at least a half a kilogram (1.1 lb) of milk chocolate. Dark chocolate has 2 to 5 times more theobromine and thus is more dangerous to dogs. According to the Merck Veterinary Manual, approximately 1.3 grams of baker's chocolate per kilogram of a dog's body weight (0.02 oz/lb) is sufficient to cause symptoms of toxicity. For example, a typical 25-gram (0.88 oz) baker's chocolate bar would be enough to bring about symptoms in a 20-kilogram (44 lb) dog. Of course, baking chocolate is rarely consumed directly due to its unpleasant taste, but other dark chocolates' canine toxicities may be extrapolated based on this figure. As dogs like the taste of chocolate products and are capable of finding and eating quantities much larger than typical human servings, they should be kept out of their reach. There are reports that mulch made from cacao bean shells is dangerous to dogs and livestock.

As a stimulant

Molten chocolate

A chocolate sweet

A model of the Reichstag made of chocolate at a Berlin shop

Chocolate contains a variety of substances, some of which have an effect on body chemistry. These include:

• Anandamide
• Arginine
• Caffeine, present in smaller amounts
• Dopamine
• Methylated xanthines (theobromine, caffeine & theophylline)
• Monoamine oxidase
• Oxalic acid
• Phenethylamine, an endogenous alkaloid sometimes described as a 'love chemical; it is quickly metabolized by monoamine oxidase-B and does not reach the brain in significant amounts
• Phenylalanine
• Serotonin
• Sugar
• Theobromine, the primary alkaloid in cocoa solids and chocolate and partly responsible for chocolate's mood-elevating effect
• Theophylline
• Tryptophan, an essential amino acid and precursor to serotonin

Chocolate is a mild stimulant to humans mainly due to the presence of theobromine. It is much more potent for horses, and its use in horse racing is prohibited.

White chocolate contains only trace amounts of the caffeine and theobromine of normal chocolates, because these chemicals are contained in the cocoa solids, not the cocoa butter, from which white chocolate is made.

Antioxidants

Chocolate is rich in phenolics especially flavan-3-ols (catechins) and flavonoids.The following table shows the phenolic and flavonoid content of three different types of chocolate.

Type of chocolate	Phenolics(mg/100g)	Flavonoids(mg/100g)
Dark chocolate	578.64 mg	28.30 mg
Milk chocolate	160.46 mg	13.48 mg
White chocolate	126.39 mg	7.70 mg

Further reading

Books

• Aaron, S. / Bearden, M. (2008). Chocolate: a healthy passion. Prometheus Books. ISBN 9781591026532
• Orey, Cal (2010). The Healing Power of Chocolate. Kensington. ISBN 9780758238207
• Pech, Julie (2010). The Chocolate Therapist. Wiley. ISBN 9780470613511

Review articles

• Corti, R. et al. “Cocoa and cardiovascular health”, Circulation. Journal of the American Heart Association (2009),119(10):1433-1441.
• Fraga, C.G. et al. ”Cocoa flavanols: effects on vascular nitric oxide and blood pressure”, Journal of Clinical Biochemistry and Nutrition (2011),48(1):63-67.
• Rimbach, G. et al. “Chocolate: (un)healthy source of polyphenols?”, Genes & Nutrition (2011),6(1):1-3.

Clinical studies

• Buitrago-Lopez, A. et al. “Chocolate consumption and cardiometabolic disorders: systematic review and meta-analysis”, BMJ (2011),343:d4488. Editorial comment by Professor Johan P. Mackenbach.
• Schroeter H, Heiss C, Balzer J et al. (January 2006). "(-)-Epicatechin mediates beneficial effects of flavanol-rich cocoa on vascular function in humans". Proc. Natl. Acad. Sci. U.S.A. 103 (4): 1024–9. doi:10.1073/pnas.0510168103. PMC 1327732. PMID 16418281. http://www.pnas.org/cgi/pmidlookup?view=long&pmid=16418281. 

External links

• World Cocoa Foundation