Coffee for hydration?

If you are a coffee drinker, I am sure you have heard many times before, whether from a nosy coworkers or the person beside you at the gym, “don’t you know coffee dehydrates you?” Well good news, it doesn’t!

So why do people think that it does? First, we need to differentiate coffee from caffeine. Coffee is the delicious beverage we tend to gravitate to first thing in the morning, brüst for example. On the other hand, caffeine is a naturally occurring compound found in coffee and other food and drinks including tea and chocolate. When caffeine is consumed in large doses (more than 500mg), it has been shown to cause a diuretic effect which causes you to pee. However, the caffeine content of a cup of coffee usually ranges between 100mg – 200mg of caffeine.

Where the dehydration effect of coffee can get a little cloudy is when we compare habitual caffeine drinkers to those who consume caffeine on a less regular basis. Individuals who drink coffee regularly (3-7 times per week) will not see any effects on their overall hydration and the volume of coffee can even contribute to their total daily fluid requirements! For those who do not consume coffee regularly (weirdos), they MAY experience a small diuretic effect, however it is not significant enough to affect their overall hydration.

To summarize… you can enjoy your brüst protein coffee without worrying about it dehydrating you!

Until next time,

Emily Fulton, MHSc RD CSCS
Registered Dietitian & Sports Nutritionist

Sources: Killer SC, Blannin AK, Jeukendrup AE (2014) No Evidence of Dehydration with Moderate Daily Coffee Intake: A Counterbalanced Cross-Over Study in a Free-Living Population. PLoS ONE 9(1): e84154. doi:10.1371/journal.pone.0084154