Health effects of chocolate

Acne

Overall evidence is insufficient to determine the relationship between chocolate consumption and acne. One preliminary study concluded that in males who are prone to acne, eating chocolate increases the severity of acne. Various studies point not to chocolate, but to the high glycemic nature of certain foods, like sugar, corn syrup, and other simple carbohydrates, as potential causes of acne, along with other possible dietary factors.

Addiction

Food, including chocolate, is not typically viewed as addictive. Some people, however, may want or crave chocolate, leading to a self-described term, chocoholic.

Sex

It has been claimed that chocolate is an aphrodisiac, but there are no rigorous studies to prove this effect.

Heart and blood vessels

Reviews support a short-term effect of lowering blood pressure by consuming cocoa products, but there is no evidence of long-term cardiovascular health benefit. While daily consumption of cocoa flavanols (minimum dose of 200 mg) appears to benefit platelet and vascular function, there is no good evidence to support an effect on heart attacks or strokes.

Stimulant

Chocolate contains caffeine and theobromine, both mild stimulants,

Weight gain

The effect of chocolate on body weight is unclear. A concern is that excessive consumption of chocolate may promote high calorie intake and weight gain, a 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 is likely to add excessive calories and induce weight gain.

Lead content

Although research suggests that even low levels of lead in the body may be harmful to children, it is unlikely that chocolate consumption in small amounts causes lead poisoning. Some studies have shown that lead may bind to cocoa shells and contamination may occur during the manufacturing process. One study showed the mean lead level in milk chocolate candy bars was 0.027  µg lead per gram of candy; another study found that some chocolate purchased at U.S. supermarkets contained up to 0.965  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. Studies concluded that "children, who are big consumers of chocolates, may be at risk of exceeding the daily limit of lead; whereas one 10 g cube of dark chocolate may contain as much as 20% of the daily lead oral limit. Moreover chocolate may not be the only source of lead in their nutrition" and "chocolate might be a significant source of Cd and Pb ingestion, particularly for children."

Polyphenol and theobromine content

Chocolate contains polyphenols, especially flavan-3-ols (catechins) and flavonoids which are under study for their potential effects in the body. The following table shows the content of phenolics, flavonoids and theobromine in three different types of chocolate.

Other animals

In sufficient amounts, the theobromine found in chocolate is toxic to animals such as cats, dogs, horses, parrots, and small rodents because they are unable to metabolise the chemical effectively. If animals are fed chocolate, the theobromine may remain in the circulation for up to 20  hours, possibly causing 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. Given access, dogs frequently consume chocolate at toxic levels because they like the taste of chocolate products and are capable of finding and eating quantities much larger than typical human servings. There are reports that mulch made from cacao bean shells is dangerous to dogs and livestock.