ItвЂ™s tough to standardize the measurement of caffeine in coffee because it depends on bean origin, flavor, roast and grind, not to mention water temperature, brewing time and, well, you get the idea вЂ¦ But a typical cup of brewed coffee has caffeine levels from 65 to 120 milligrams while a shot of espresso ranges from 30 to 50 milligrams. So we caution against overuse in kids,вЂќ says Sridhar. вЂњChildren weigh less and are more prone to its effects. вЂњWhile the response to caffeine varies, 400 milligrams or above is generally the amount considered excessive for adults,вЂќ says Arun Sridhar, M.B.B.S., M.P.H., a cardiac electrophysiologist and specialist in heart rhythm disorders at UW Medicine Heart Institute.ДЄnd itвЂ™s important to know that the maximum tolerated dose of caffeine differs between adults and children. ThatвЂ™s because your genetics, age, weight, tolerance and liver all play a role in how quickly you process caffeine. But now what? How much is too muchД®verybody metabolizes caffeine differently.

Over-the-top coffee consumption is how you tolerate a day in the life. Your eyelid is twitching, your heart is going thumpa thumpa and your leg is doing the cha-cha. Maybe that espresso chaser wasnвЂ™t such a good idea after all. You were just trying to get the wake-up job done and now this.

Caffeine overdose