A 2017 study from the Journal of Food and Chemical Toxicology determined that up to 400 mg of caffeine per day was safe for most people. For many of us, this caffeine comes in the form of coffee, and if you are drinking multiple cups per day, especially without breaks, you could be risking your health. According to the Mayo Clinic, a single one-ounce shot of espresso contains 63 mg of caffeine. That means if you have much more than six shots, which total 378 mg, you’ll be over your 400 mg limit.
The tricky thing about caffeine is that it’s not always a hard and fast rule. The type of bean plays an important role in your espresso’s caffeine content. Robusta beans have a higher level of caffeine than most, for instance. Depending on the beans, how they were roasted, and how they were brewed, Robusta could have twice as much caffeine as Arabica.
Time also plays a role in how your body handles caffeine. Drinking six shots of espresso back-to-back will hit you much harder than spreading them out over several hours. That’s because caffeine’s half-life is five hours. So if you have a caffè latte, typically made with two espresso shots, at 7 a.m. and consume around 126 mg of caffeine, only 63 mg will be left in your system by lunchtime.
Caffeine is a numbers game
You might think at this point that you could have your six shots in the morning and build yourself up to 378 mg and then wait five hours before having three more shots. But the 400 mg limit is not how much your system can handle at any one time; it’s your total daily limit. Even with the half-life of five hours, it’s not recommended you go over 400 mg in a day.
You’ll have to pay attention to what kind of drinks you’re consuming during the day to know where you’re at, because these numbers are not consistent from brand to brand. For example, caffeine in espresso drinks at Starbucks and Nespresso pods can vary.
Nespresso pods range from 50 mg per cup for some of its espresso blends up to 80 mg for a minuscule 25 ml ristretto. And then there’s the Kazaar, which, at just a 25 ml shot, contains a whopping 120 mg of caffeine. It also sat just above the middle of the pack when we ranked Nespresso pod flavors.
Starbucks lists a 1.5-ounce shot of espresso at 150 mg of caffeine, and most of its drinks come with two to three shots for a total of between 300 and 450 mg of caffeine. So, remember to pace yourself with the espresso. Have some to kickstart your day, maybe one of these 13 store-bought brands, and then take it easy later.
