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
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News tagged with caffeine
Caffeine doesn't reverse the negative cognitive impact of alcohol, study shows
Medicine & Health / Psychology & Psychiatry
Dec 07, 2009 |
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People who drink may want to know that coffee won't sober them up, according to new laboratory research. Instead, a cup of coffee may make it harder for people to realize they're drunk.
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 ...
Will giving coffee to babies keep them awake as adults?
Oct 08, 2009 |
4.5 / 5 (2) |
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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.
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 ...
Relieve headaches by knowing the cause
Aug 28, 2009 |
5 / 5 (1) |
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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 ...
Bad news for coffee drinkers who get headaches
Aug 14, 2009 |
not rated yet |
2
High caffeine consumption, more headaches?
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 ...
Caffeine reverses memory impairment in Alzheimer's mice
Jul 06, 2009 |
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3
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 ...
Caffeine intake prevents risk taking after extreme sleep deprivation
Jun 10, 2009 |
3 / 5 (1) |
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Caffeine use prevents increased risk taking that occurs after several nights of total sleep deprivation, according to new research. Results indicate that despite extreme sleep deprivation, participants who had consumed caffeine ...
Adolescent obesity linked to reduced sleep caused by technology use and caffeine
Jun 09, 2009 |
not rated yet |
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According to a research abstract that will be presented at SLEEP 2009, the 23rd Annual Meeting of the Associated Professional Sleep Societies, adolescent obesity is associated with having less sleep. Reduction in sleep could ...
Your brain on -- and off -- caffeine
May 01, 2009 |
3.7 / 5 (14) |
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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 |
4.7 / 5 (7) |
5
(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.
Plug that energy drain
Jan 26, 2009 |
4 / 5 (3) |
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January makes you want to eat potatoes, drink wine and sleep forever. The days are dark and short, seasonal depression causes fatigue and the couch is often far more inviting than the frigid outdoors.
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 ...
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.
