There is no realistic scenario where, no matter your extractions or bean selections, 6-10 shots of espresso a day is not an enormous amount of caffeine
replyA grande americano at Starbucks is a 16 oz drink with three shots of espresso. Have one in the morning and one in the afternoon and you are at six shots of espresso. That doesn't seem all that enormous to me.
reply75mg per shot = 450mg caffeine
replyThat's a bit over the recommended limit of 400mg a day the Mayo Clinic, FDA, etc. recommend. Not sure it it qualifies as 'enormous' or not.
caffeine extraction is largely a function of time in contact with water. Espresso is quite quick brew, so has less caffeine than other brewing methods (yes, there are plenty of other factors)
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