Definition of Caffeine in the diet:

Caffeine is a substance that is found in certain plants. It can also be man-made (produced synthetically) and then added to food products. It is a central nervous system stimulant and a diuretic (substance that helps rid your body of fluids).

Function:

Caffeine is absorbed and passes quickly into the brain. It does not collect in the bloodstream or get 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 will not reduce the effects of alcohol, although many people still believe a cup of coffee will help a person "sober-up."

Caffeine may be used for the short-term relief of fatigue or drowsiness.