Monday, January 16, 2006

Dedicated to a Chocoholic who is apparently FOOLED

Physiological effects

Toxicity in animals

In sufficient amounts the theobromine found in chocolate is toxic to animals such as horses, dogs, parrots, voles, and cats (kittens especially) 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 involves inducing vomiting within two hours of ingestion, or contacting a veterinarian.
A typical 20-kilogram dog will normally experience intestinal distress after eating less than 240 grams of milk chocolate, but will not necessarily experience bradycardia or tachycardia unless it eats at least a half a kilogram of milk chocolate. If it does not expel the chocolate from its system because of the fat and sugar content, then it would have a 50% chance of surviving after eating 5 kilograms. Dark, sweet chocolate has about 50% 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 baker's chocolate bar would be enough to bring about symptoms in a 20-kilogram dog.

Health benefits
Recent studies have shown that cocoa or dark chocolate has potent health benefits for people. Dark chocolate is full of the flavonoids epicatechin and gallic acid, which are antioxidants that help protect blood vessels, promote cardiac health, and prevent cancer. It also has been effectively demonstrated to counteract mild hypertension. In fact, dark chocolate has more flavonoids than any other antioxidant-rich food such as red wine, green and black tea, and blueberries. There has even been a fad diet named "Chocolate diet" that emphasises eating chocolate and cocoa powder in capsules. However, consuming milk chocolate or white chocolate, or drinking milk with dark chocolate, appears to largely negate the health benefits. Chocolate is also a calorie-rich food with a high content of saturated fat, so daily intake of chocolate also requires reducing caloric intake of other foods.
Two-thirds of the fat in chocolate comes in the form of two saturated fats called stearic acid and oleic acid. However, unlike other saturated fats, these two do not raise levels of LDL cholesterol in the bloodstream. A 2001 study by researchers at Penn State University found that the flavonoids in chocolate slowed the oxidation of LDL cholesterol, a process that is believed to lead to atherosclerosis.

Medical applications

Mars, Incorporated, a Virginia-based candy company, spends millions of dollars each year on flavanol research. The company is in talks with pharmaceutical companies to license drugs based on synthesised cocoa flavanol 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.
Mars is presently marketing the Cocoavia™ brand , a line of functional food chocolates which have cholesterol-reducing phytosterols and at least 100 milligrams of flavanols. The snacks are designed to be eaten primarily for heart benefits, and as such, Mars has recommended a regimen of two snacks per day.
Chocolate as a drug
Current research indicates that chocolate is a weak stimulant because of its content of theobromine. However, chocolate contains too little of this compound for a reasonable serving to create effects in humans that are on par with a coffee buzz. Aptly spoken by the pharmacologist Ryan J. Huxtable, "[Chocolate is] more than a food but less than a drug". However, chocolate is a very potent stimulant for dogs and horses; its use is therefore banned in horse-racing. Some chocolate products contain synthetic caffeine as an additive.
Chocolate also contains small quantities of the endogenous cannabinoid anandamide and the cannabinoid breakdown inhibitors N-oleoylethanolamine and N-linolenoylethanolamine. Anandamides are produced naturally by the body, in such a way that their effects are extremely targeted (compared to the broad systemic effects of drugs like tetrahydrocannabinol) and relatively short-lived. In experiments N-oleoylethanolamine and N-linolenoylethanolamine interfere with the body's natural mechanisms for breaking down endogenous cannabinoids, causing them to last longer. However, noticeable effects of chocolate related to this mechanism in humans have not yet been demonstrated.
Pleasure of consuming chocolate
Part of the pleasure of eating chocolate is ascribed to the fact that its melting point is slightly below human body temperature and, therefore, melts in the mouth. Chocolate also releases serotonin in the brain which produces feelings of pleasure in a similar way to sunlight. Although chemicals are released in certain areas of the brain, chocolate does not contain a significant amount of these chemicals so as to harm or affect human behaviour.
Research has shown that heroin addicts tend to have an increased liking for chocolate because it triggers dopamine release in the brain – an effect, albeit a legal one, similar to that of opium
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Chocolate as an 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. More recently, suggestion has been made that serotonin and other chemicals found in chocolate, most notably phenethylamine, can act as mild sexual stimulants. While there is no firm proof that chocolate is indeed an aphrodisiac, giving a gift of chocolate to one's sweetheart is a familiar courtship ritual.

Acne

There is a popular belief that the consumption of chocolate can cause acne. Such an effect could not be shown in scientific studies as the results are inconclusive.
Chocolate, ranging from dark to light, can be moulded and decorated like these chickens with ribbons.


Lead

Chocolate has one of the highest concentrations of lead among all products that constitute a typical Westerner's diet. This is thought to happen because the cocoa beans are mostly grown in developing countries such as Nigeria. Those countries still use tetra-ethyl lead as a gasoline additive and, consequently, have high atmospheric concentrations of lead. According to the U.S. Food and Drug Administration, levels of lead in chocolate are sufficiently low that even people who eat large amounts of chocolate every day are not at risk of any adverse effects.


»Chocodip«

Chocolate contains small quantities of anandamide, an endogenous cannabinoid found in the brain. Sceptics claim one would need to consume several pounds of chocolate to gain any very noticeable psychoactive effects; and eat a lot more to get fully stoned. Yet it's worth noting that N-oleolethanolamine and N-linoleoylethanolamine, two structural cousins of anandamide present in chocolate, both inhibit the metabolism of anandamide. It has been speculated that they promote and prolong the feeling of well-being induced by anandamide.
Chocolate contains caffeine. But the caffeine is present only in modest quantities. It is easily obtained from other sources.
Chocolate's theobromine content may contribute to - but seems unlikely to determine - its subtle but distinctive psychoactive profile. Surprisingly, perhaps, recent research suggests that pure theobromine may be superior to opiates as a cough medicine due to its action on the vagus nerve.
Chocolate also contains tryptophan. Tryptophan is an essential amino acid. It is the rate-limiting step in the production of the mood-modulating neurotransmitter serotonin. Enhanced serotonin function typically diminishes anxiety. Yet tryptophan can normally be obtained from other sources as well; and only an unusually low-protein, high-carbohydrate meal will significantly increase its rate of intake into the brain.
Like other palatable sweet foods, consumption of chocolate triggers the release of endorphins, the body's endogenous opiates. Enhanced endorphin-release reduces the chocolate-eater's sensitivity to pain. Endorphins probably contribute to the warm inner glow induced in susceptible chocaholics.
Acute monthly cravings for chocolate amongst pre-menstrual women may be partly explained by its rich magnesium content. Magnesium deficiency exacerbates PMT. Before menstruation, too, levels of the hormone progesterone are high. Progesterone promotes fat storage, preventing its use as fuel; elevated pre-menstrual levels of progesterone may cause a periodic craving for fatty foods. One study reported that 91% of chocolate-cravings associated with the menstrual cycle occurred between ovulation and the start of menstruation. Chocolate cravings are admitted by 15% of men and around 40% of women. Cravings are usually most intense in the late afternoon and early evening.

Cacao and chocolate bars contain a group of neuroactive alkaloids known as tetrahydro-beta-carbolines. Tetrahydro-beta-carbolines are also found in beer, wine and liquor; they have been linked to alcoholism. But the possible role of these chemicals in chocolate addiction remains unclear.
Perhaps chocolate's key ingredient is its phenylethylamine (PEA) "love-chemical". Yet the role of the "chocolate amphetamine" is disputed. Most if not all chocolate-derived phenylethylamine is metabolised before it reaches the CNS. Some people may be sensitive to its effects in very small quantities.
Phenylethylamine is itself a naturally occurring trace amine in the brain. Phenylethylamine releases dopamine in the mesolimbic pleasure-centres; it peaks during orgasm. Taken in unnaturally high doses, phenylethylamine can produce stereotyped behaviour more prominently even than amphetamine. Phenylethylamine has distinct binding sites but no specific neurons. It helps mediate feelings of attraction, excitement, giddiness, apprehension and euphoria. One of its metabolites is unusually high in subjects with paranoid schizophrenia.
There is even a phenylethylamine theory of depression. Monoamine oxidase type-b has been described as phenylethylaminase; and taking a selective MAO-b inhibitor, such as selegiline (l-deprenyl, Eldepryl) or rasagiline (Agilect) can accentuate chocolate's effects. Some subjects report that bupropion (Wellbutrin, Zyban) reduces their chocolate-cravings; but other chocaholics dispute this.