Sport Caffeine and Hydration

[Quinnch]

I have always wondered what the link was between caffeine and dehydration. I know everyone says "caffeine dehydrates you," but let me pose an interesting question.

If you drink a large cup of coffee, it is basically coffee grounds mixed with a lot of water. How would this differ from drinking an espresso shot followed by a glass of pure water? I've heard people say "drink one glass of water for every cup of coffee you drink" but isn't this all relative to the amount of caffeine in the coffee? Wouldn't drinking a glass of strong coffee followed by a glass of water be exactly the same as drinking a large diluted cup of coffee?

 

[malkore]

caffine is a diuretic, it doesn't 'dehydrate' you so much as it causes some water to exit the body to deal with removing the caffine.

same for soda pop and even beer. these are less hydrating than pure water, but if you only drank beer/soda/coffee, you wouldn't die of dehydration.

if you don't feel dehydrated, you are fine.

 

[matt182]

Coffee is only a mild diuretic, so one glass of water for one glass of coffee is totally wrong.

I think its basis is the fact it acts directly on the kidneys, enhancing water excretion - albeit minimally.