Coffee (and caffeine in general) is an integral part of the daily routine for many. But how much coffee is too much? Let's separate the facts from the myths.
How much caffeine in a cup of coffee?
In order to get an understanding of what we are talking about, it is helpful to know how much caffeine is in one cup of coffee.
Following the American cup measurement, one cup should be eight fluid ounces (about 240 ml). However, the standard for hot beverages is six fluid ounces (about 180 ml). Therefore, depending on how you make your coffee, a small 6 fl. oz cup of brewed coffee contains about 85 mg of caffeine.
For reference, an average cup of espresso contains about 63 mg of caffeine (a commonly ordered double espresso, therefore, contains about 126 mg of caffeine). An average 8.4 Fl Oz (250 ml) can of energy drink contains about 80 mg of caffeine. For those that use pre-workout powders, be warned a single scoop can contain over 300mg of caffeine.
How much coffee is too much?
So, how much caffeine is too much caffeine? According to prof.dr.ir. Ellen Kampman (from Wageningen University & Research), an average person, can handle a maximum of 400mg of caffeine per day. Following our standardized cups mentioned above, this amounts to about 4 to 5 cups of coffee or 6 standardized espressos.
In addition, it is not recommended to exceed an intake of 200mg per sitting, which means that you should avoid drinking more than 2 cups of coffee or 3 espressos over a short period of time.
Take into account that these estimates are averages and depend on various factors, such as your weight and the condition of your liver. For example, if you are larger than the average person, you will likely be able to handle more caffeine; the same goes the other way around if you are smaller than the average person.
What happens if you drink too much coffee?
According to professor Kampman, you are at risk of developing some unpleasant side effects if you exceed the above-mentioned caffeine intake.
Some common defects are anxiety, irritability, stress, and headaches. On the extreme side of things, there are reports of incidents where people even end up in intensive care due to excessive caffeine intake over a short period of time. This makes sense when you think about it. Similarly, drinking three glasses of beer or wine in 10 minutes is worse for your health than drinking the same amount over the span of an evening.
So, all in all, please be careful with your daily caffeine intake. This is not to say that coffee is unhealthy, though. On the contrary, according to professor Kampman, a few cups of coffee a day can even be healthy. But, as with all things, moderation is key.
More on coffee:
How to make the perfect cup of coffee – with a little help from science (Universal-Sci)
Research Check: will a coffee a day really keep heart attacks at bay? (Universal-Sci)
Could coffee be the secret to fighting obesity? (Universal-Sci)
Sources and further reading:
Health Check: does caffeine cause dehydration? (Universal-Sci)
Variations in caffeine and chlorogenic acid contents of coffees: what are we drinking? (national library of medicine)
Prof.dr.ir. E (Ellen) Kampman - Wageningen University via Universiteit van Nederland
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