It all depends on your body weight and the time that passes from cup to cup, caffeine can be found in numerous products so you might be in danger with less the five cups. Usually an acute overdose of caffeine would be 400 milligrams which is more than 3-4 cups of coffee. In cases of extreme overdose, death can result; this lethal amount of caffeine in humans is dependent on weight and individual sensitivity and estimated to be about 150 to 200 milligrams per kilogram of body mass, which is roughly 80 to 100 cups of coffee for an average adult.
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