Caffeine question?

i know caffeine dehydrates us (or can) but i have never known why-anyone know how this happens? can explain just how it causes us to dehydrate? thank you
Answer:
Put simply, caffiene is a diuretic. This means it forces your body to excrete more water through your kidneys producing a more dilute urine. See the link for (what may be an overly complicated) explanation.

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I believe it is the amount of sugar in the drink; not the caffiene.

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I have never heard about this ..

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People used to think that when u drink coffee and other caffeinated beverages, u would be dehydrating yourself. Yes, coffee is a diuretic... but the thing is, it is considered as a MILD diuretic. Meaning, it does cause you to pee a more dilute urine but you also retain some of the liquids that you had just consumed.
Recent evidence also shows that the more often you drink caffeinated drinks, the more your body gets immune to its diuretic effect... for more info, please check out the website I found.

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