The use of beverages that contain caffeine has been debated for centuries. In almost every part of the world where coffee and tea have been available, religious or government leaders have tried to ban or restrict its use. All such attempts, until the present time, lacked scientific credibility.
2 New studies linking caffeine use to central nervous system problems and birth defects in test animals have prompted scientists and policy makers in the U.S. to reconsider caffeine’s regulatory status. This is a complex task, however, because caffeine is regulated under three different sections of the Federal Food, Drug, and Cosmetic Act. It is a natural ingredient in coffee and tea. A food addictive in soft drink, and an added ingredient in over-the-counter drugs.
3 Foods containing any poisonous or hazardous substance are defined as adulterated and prohibited by the Food and Drug Act. However, foods which naturally contain harmful substances may be permitted if the amount of the substance does not ordinarily injure health. Thus, foods containing caffeine, like coffee and tea, are approved despite caffeine’s health effects at high dose levels.
4 As a food additive, caffeine is regulated as a “generally recognize it safe” (GRAS) substance. Because of this regulatory status, food processors are not required to prove caffeine’s safety before adding it to their products. Instead, caffeine’s long and widespread history of use is considerate sufficient proof of safety. The Food and Drug Administration (FDA) has published rules which limit the amount of caffeine that can be added to foods.
( “The health Effects of caffeine” by American council on Science and Health)