Caffeine is classified by the FDA and generally recognized as safe and there has been no evidence produced that shows caffeine to be harmful to health. The American Medical Association holds a similar view as long as the substance is consumed in moderation.
It has become a common belief that moderation and common sense when ingesting this substance as well as any other substance in anyone’s diet is the key to health. Moderation is considered the equivalent of about three cups of coffee, but of course it depends on the individual’s body mass and ability to process the substance.
Some people display a sensitivity towards caffeine and can only drink a small amount before they start feeling jittery and over stimulated, while others can drink a large amount of caffeine and fall right to sleep soon after. Caffeine does not accumulate in the blood stream or tissues, it is evacuated from the body within hours of consumption. This substance has been used to increase alertness in tired individuals in many different products including some in pill form. There appears to be no difference in the way a child’s body and an adult’s body reacts to caffeine other than the body mass compared to the amount of caffeine consumed.
Very basically, when consuming things that contain caffeine, do it in moderation, taking into account past history as far as its effects on your body.
Source: health in life blog
Sonja Franzmann is Miss Fit, a Personal Fitness Trainer, Nutrition Consultant and PTS Certified Trainer. Miss Fit’s goal is to empower you with the knowledge and skills to make intelligent decisions regarding nutrition and active living. 
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