Caffeine is absorbed and passes quickly to the brain. It does not accumulate in the bloodstream nor is it stored in the body. It leaves the body in the urine many hours after it has been consumed.
There is no nutritional need for caffeine. It can be avoided in the diet.
Caffeine stimulates or excites the brain and nervous system. It does not lessen the effects of alcohol, although many people still believe that a cup of coffee will help a person stay "sober."
Caffeine can be used for the short-term relief of fatigue or drowsiness.
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