Caffeine
hideCaffeine is a bitter, white crystalline xanthine alkaloid that is a psychoactive stimulant drug. Caffeine was discovered by a German chemist, Friedrich Ferdinand Runge, in 1819. He coined the term "kaffein", a chemical compound in coffee, which in English became caffeine. Caffeine is also part of the chemical mixtures and insoluble complexes guaranine found in guarana, mateine found in mate, and theine found in tea; all of which contain additional alkaloids such as the cardiac stimulants theophylline and theobromine, and often other chemicals such as polyphenols which can form insoluble complexes with caffeine.
Caffeine is found in varying quantities in the beans, leaves, and fruit of some plants, where it acts as a natural pesticide that paralyzes and kills certain insects feeding on the plants. It is most commonly consumed by humans in infusions extracted from the cherries of the coffee plant and the leaves of the tea bush, as well as from various foods and drinks containing products derived from the kola nut. Other sources include yerba mate, guarana berries, and the Yaupon Holly.
In humans, caffeine is a central nervous system (CNS) stimulant, having the effect of temporarily warding off drowsiness and restoring alertness. Beverages containing caffeine, such as coffee, tea, soft drinks, and energy drinks enjoy great popularity. Caffeine is the world's most widely consumed psychoactive substance, but unlike many other psychoactive substances it is legal and unregulated in nearly all jurisdictions. In North America, 90% of adults consume caffeine daily. The U.S. Food and Drug Administration lists caffeine as a "Multiple Purpose Generally Recognized as Safe Food Substance".
Caffeine has diuretic properties, at least when administered in sufficient doses to subjects who do not have a tolerance for it. Regular users, however, develop a strong tolerance to this effect, and studies have generally failed to support the common notion that ordinary consumption of caffeinated beverages contributes significantly to dehydration.
For more information about Caffeine, read the full article at
Wikipedia.
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News tagged with caffeine
Caffeine reverses memory impairment in Alzheimer's mice
Jul 06, 2009 |
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Coffee drinkers may have another reason to pour that extra cup. When aged mice bred to develop symptoms of Alzheimer's disease were given caffeine - the equivalent of five cups of coffee a day - their memory ...
Java and nighttime jobs don't mix: study
Nov 03, 2009 |
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Night-shift workers should avoid drinking coffee if they wish to improve their sleep, according to research published in the journal Sleep Medicine. A new study led by Julie Carrier, a Université de Montréal psycho ...
Bad news for coffee drinkers who get headaches
Aug 14, 2009 |
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High caffeine consumption, more headaches?
Your brain on -- and off -- caffeine
May 01, 2009 |
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Ever miss your daily cup of coffee and subsequently get a pounding headache? According to reports from consumers of coffee and other caffeinated products, caffeine withdrawal is often characterized by a headache, ...
A little java makes it easier to jive, researcher says
Mar 30, 2009 |
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(PhysOrg.com) -- Stopping to smell the coffee - and enjoy a cup of it - before your morning workout might do more than just get your juices flowing. It might keep you going for reasons you haven’t even considered.
High caffeine intake linked to hallucination proneness
Jan 14, 2009 |
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High caffeine consumption could be linked to a greater tendency to hallucinate, a new research study suggests.
A low dose of caffeine when pregnant may damage the heart of offspring for a lifetime
Dec 16, 2008 |
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A new study published online in The FASEB Journal shows that the equivalent of one dose of caffeine (just two cups of coffee) ingested during pregnancy may be enough to affect fetal heart development and then reduce heart ...
High caffeine intake can lead to arrhythmias
Aug 31, 2009 |
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Coffee is routinely consumed in countries within the Mediterranean basin. Coffee, an infusion of ground, roasted coffee beans, is the most widely consumed behaviourally active substance in the world. It contains ...
Caffeine experts call for warning labels for energy drinks
Sep 24, 2008 |
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Johns Hopkins scientists who have spent decades researching the effects of caffeine report that a slew of caffeinated energy drinks now on the market should carry prominent labels that note caffeine doses and warn of potential ...
Consuming small amounts of caffeine when pregnant may affect the growth of an unborn child
Nov 03, 2008 |
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Consuming caffeine at any time during pregnancy is associated with an increased risk of fetal growth restriction (low birth weight), according to research published on bmj.com today.
New study aims to reduce risk of childhood leukemia
Jan 26, 2009 |
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A study led by Dr Marcus Cooke at the University of Leicester and funded by World Cancer Research Fund (WCRF) UK is looking at whether consuming caffeine during pregnancy might affect the unborn baby's risk of developing ...
Relieve headaches by knowing the cause
Aug 28, 2009 |
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When it comes to fighting headaches, instant gratification is ideal. It's easy to pop a couple of pain pills and move on with your daily activities. But doctors say the most common remedy used by headache sufferers could ...
Will giving coffee to babies keep them awake as adults?
Oct 08, 2009 |
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An F1000 evaluation looks at a Canadian study on how giving caffeine to newborn rats has a long-lasting and detrimental effect on sleep and breathing in adulthood.
Java gives caffeine-naive a boost, too
Aug 26, 2008 |
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New research from the University of Alberta in Edmonton, Canada, shows that—for women—the caffeine advantage is indeed everything it's cracked up to be. Females who don't drink coffee can get just as much of a caffeine boost ...
Teens Fueled by Caffeine Use Too Much Technology and Don’t Get Enough Sleep
Jul 20, 2009 |
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(PhysOrg.com) -- Fueled by caffeine teens are up late at night, and they aren’t just focusing on homework. Web surfing, text messaging and gaming are keeping them up for hours into the night, according to a recent study by ...
