A cup of green tea has around 28 milligrams (mg) of caffeine, which places it marginally behind black tea’s 47 mg, based on the Mayo Clinic. Having said that, there may be lots of variation in caffeine information based upon how tea is processed and brewed. Kelly Kennedy is https://www.goteaworld.com/arizona-green-tea-is-it-good-for-you-5-facts/