Nutrition One hundred grams of milk chocolate supplies 540
calories. It is 59%
carbohydrates (52% as
sugar and 3% as
dietary fiber), 30% fat and 8%
protein (table). Approximately 65% of the fat in milk chocolate is
saturated, mainly
palmitic acid and
stearic acid, while the predominant
unsaturated fat is
oleic acid (table). One hundred grams of milk chocolate is an
excellent source (over 19% of the
Daily Value, DV) of
riboflavin,
vitamin B12 and the
dietary minerals manganese,
phosphorus and
zinc. Chocolate is a
good source (10–19% DV) of
calcium,
magnesium and
iron.
Phytochemicals Chocolate contains
polyphenols, especially
flavan-3-ols (catechins) and smaller amounts of other
flavonoids. It also contains
alkaloids, such as
theobromine,
phenethylamine, and
caffeine, which are under study for their potential effects in the body.
Heavy metals 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. 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, [as] 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
cadmium and lead ingestion, particularly for children." According to a 2005 study, the average
lead concentration of cocoa beans is ≤ 0.5 ng/g, which is one of the lowest reported values for a natural food. The
European Food Safety Authority recommended a tolerable weekly intake for cadmium of 2.5
micrograms per kg of body weight for Europeans, indicating that consuming chocolate products caused exposure of about 4% among all foods eaten. Maximum levels for baby foods and chocolate/cocoa products were established under Commission Regulation (EU) No 488/2014.
1986 California Proposition 65 requires a warning label on chocolate products having more than 4.1 mg of cadmium per daily serving of a single product.
Caffeine One tablespoonful (5 grams) of dry unsweetened
cocoa powder has 12.1 mg of caffeine and a 25-g single serving of dark chocolate has 22.4 mg of caffeine. This is much less than the amount found in coffee, of which a single 7 oz. (200 ml) serving may contain 80–175 mg of caffeine, though studies have shown psychoactive effects in caffeine doses as low as 9 mg, and a dose as low as 12.5 mg was shown to have effects on cognitive performance.
Theobromine and oxalate Chocolate may be a factor for
heartburn in some people because one of its constituents, theobromine, may affect the
esophageal sphincter muscle in a way that permits stomach acids to enter the
esophagus.
Theobromine poisoning is an overdosage reaction to the bitter alkaloid, which happens more frequently in
domestic animals than humans. However, daily intake of 50–100 g cocoa (0.8–1.5 g theobromine) by humans has been associated with sweating, trembling, and severe headache. Chocolate and cocoa contain moderate to high amounts of
oxalate, which may increase the risk of
kidney stones.
Non-human 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
metabolize 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 dog will normally experience great intestinal distress after eating less than 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 baker's chocolate bar would be enough to bring about symptoms in a dog. In the 20th century, there were reports that
mulch made from cocoa bean shells is dangerous to dogs and livestock.
Research Commonly consumed chocolate is high in
fat and
sugar, which are associated with an increased risk for
obesity when chocolate is consumed in excess. Overall evidence is insufficient to determine the relationship between chocolate consumption and
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. Food, including chocolate, is not typically viewed as
addictive. Some people, however, may want or crave chocolate, By some
popular myths, chocolate is considered to be a
mood enhancer, such as by increasing
sex drive or stimulating
cognition, but there is little scientific evidence that such effects are consistent among all chocolate consumers. If mood improvement from eating chocolate occurs, there is not enough research to indicate whether it results from the favorable flavor or from the
stimulant effects of its constituents, such as caffeine, theobromine, or their parent molecule,
methylxanthine. Reviews support a short-term effect of lowering blood pressure by consuming cocoa products, but there is limited evidence of long-term cardiovascular health benefit. Chocolate and cocoa are under preliminary research to determine if consumption affects the risk of certain
cardiovascular diseases. Daily consumption of cocoa flavanols (minimum dose of 200 mg) appears to benefit
platelet and vascular function. ==Labeling==