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Alternative names
Diet - caffeineDefinition Return to top
Caffeine is a substance that exists naturally in certain plants. It can also be produced synthetically and used as an additive in food products. It is a central nervous system stimulant and a diuretic.Function Return to top
Caffeine is absorbed and distributed very quickly. After absorption, it passes into the brain. "Caffeine sensitivity" refers to the amount of caffeine that will produce negative side effects. This amount will vary from person to person.
Caffeine does not accumulate in the bloodstream nor is it stored in the body. It is excreted in the urine many hours after it has been consumed.
Caffeine will not reduce the effects of alcohol, although many people still believe a cup of coffee will "sober up" an intoxicated person.
Caffeine may be used as a treatment for migraine headaches and in relieving, for a short time, fatigue or drowsiness.
Food Sources Return to top
Caffeine is widely consumed. It is found naturally in the leaves, seeds, and fruits of more than 60 plants, including tea leaves, kola nuts, coffee, and cocoa beans. It is in coffee, tea, chocolate, cocoa and many carbonated beverages such as colas.Side Effects Return to top
Excessive caffeine intake can lead to a fast heart rate, diuresis (excessive urination), nausea and vomiting, restlessness, anxiety, depression, tremors, and difficulty sleeping.
The effect of caffeine on health has been widely studied. In particular, the effects of caffeine on fibrocystic breast disease, cardiovascular disease, birth defects, reproductive function, and behavior in children has been closely examined and linked to some but not all.
A 1984 statement from the American Medical Association Council on Scientific Affairs stated "Moderate tea or coffee drinkers probably have no concern for their health relative to their caffeine consumption provided other lifestyle habits (diet, alcohol consumption) are moderate as well." This statement emphasizes moderate caffeine use.
Abrupt withdrawal of caffeine may cause headaches, drowsiness, irritability, nausea, vomiting, and other symptoms. Reduce caffeine intake gradually to prevent any symptoms of withdrawal.
Recommendations Return to top
There is no human requirement for caffeine in the diet. Moderate caffeine intake, however, is not associated with any health risk. Three 8 oz. cups of coffee (250 milligrams of caffeine) per day is considered an average or moderate amount of caffeine. Ten 8 oz. cups of coffee per day is considered excessive intake of caffeine.
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Page last updated: 28 October 2004 |