Caffeine, currently the world's most widely used behavior altering drug, has actually been used by humans for centuries. The first ever recorded use was around 2700 B.C. when Chinese emperor Shen Nung regularly consumed tea. Around 575 A.D. Africans used coffee beans as money and consumed them for food but it wasn't until around 1865 that caffeine was found to be the active substance in such foods as tea, coffee, mate, and kola nuts that were used by people worldwide.
Chemically caffeine is an alkaloid, or a complex organic base found in nature in seed bearing plants. As a drug it is labeled a central nervous system stimulant. Caffeine's real name is 1, 3, 7-trimethylxanthine which means it's a xanthine molecule with methyl groups bonded to the number 1, 3, and 7 carbon atoms. Two products of caffeine's breakdown are theophyline (1, 3 dimethylxanthine) and theobromine (3, 7 dimethylxanthine) which both produce effects similar to caffeine in a person and are both found in coffee and tea.
Caffeine is found naturally throughout the world in over sixty different kinds of plants. Coffee beans are used for coffee and tea leaves for tea, both containing about four percent caffeine. Chocolate comes for the caffeine containing pods of the Theobroma cacao tree. Though not as much is used as in the past, a part of the caffeine in soft drinks comes from the kola nut of the cola nitida tree. Mate leaves, used in the drink "mate", guarana seeds, and yucca bark are also major sources of caffeine in many cultures throughout the world.
Caffeine is one of the most used and widely accepted drugs. More than sixty percent of adults in North America consume caffeine on a daily basis. Even in the 1960's when a substantial drop in coffee consumption swept the country, soft drink sales increased so rapidly that the per capita caffeine consumption stayed about constant. Even though the U.S. per person consumption of caffeine per day is about three times the world's average of 70 mg (U.S. stands at 211 mg currently), it actually has a lower average than most industrialized countries. Canada has an average of 238 mg of caffeine each day, Sweden is next with 425 mg, and the UK tops the polls at 444 mg of the stuff each day on average.
Caffeine is a drug that alters perception, attitude, and the metabolism. Physically it increases the circulation of fatty acids in the body which results in their enhanced oxidation which increases energy in the body. This is one reason that runners and other endurance athletes often use caffeine in training and competition. It also relaxes smooth muscle tissue and speeds up cardiac muscle contractions which causes both calmness and alertness simultaneously, another important reason its used by athletes. Because of these occurrences, caffeine is used to treat asthma, chronic obstructive pulmonary disease, neonatal spasms, and to relieve overdoses of opiates and central depressants. A third physical effect is the constriction of cerebral blood vessels, changing the person's mental state.
Stimulated mood and behavior, decreased fatigue, and increased energy, alertness, and activity are all effects of caffeine. Doses of caffeine as small as 10 mg have been seen to alter self reports of mood. Thirty-two milligrams can improve vigilance, performance, and reaction time. Doses up to about 200 mg a day can increase tapping speed, postpone sleep, increase motivation to work, desire to talk to people, and improve self confidence. Higher daily doses can, depending on the individual, either improve or disrupt performance of complex tasks, increase physical endurance, work output, nervousness, jitteriness, restlessness, and anxiousness, though it almost never goes without any effect.
People naturally assume that since caffeine is a drug that there are major health problems associated with it and have been trying hard to find one. A number of rumors have gone around, just as with everything else that's ok to consume one day and is fatal the next, about such effects of caffeine and an equal number of studies have been conducted to try and counter those myths. In the end, caffeine seems to be ok every time. At one time caffeine was thought to be a cancer causing substance but studies of 16,600 people in Norway and 7,350 people in Hawaii found no relationship between coffee