[jrockway]

Caffeine isn't a diuretic if you use it regularly. From Wikipedia: "Regular users of caffeine have been shown to develop a strong tolerance to the diuretic effect, and studies have generally failed to support the notion that ordinary consumption of caffeinated beverages contributes significantly to dehydration, even in athletes."

[klausa]

To support you more, from [1]:

"Contrary to popular belief, caffeine does not act as a diuretic when consumed in moderation (less than five cups a day or 500 to 600 milligrams), and does not lead to dehydration or to a water-electrolyte imbalance; current evidence suggests that caffeinated beverages contribute to the body's daily fluid requirements no differently from pure water."

This particular misconception is kind of a pet peeve of mine, and it drives me nuts how widespread it is.

[1]: http://en.wikipedia.org/wiki/Health_effects_of_coffee#Laxati...

[trafficlight]

As a consumer of copious amounts of caffeinated beverages, I have anecdotal evidence to back this up.

[neurotech1]

As someone who has consumed copious * 10 amounts of caffeine, I would disagree. The tolerance to the diuretic effect isn't that much. What some people refer to as "tolerance" is more the effect of dehydration. Of course, drinking large quantities of water to balance the large quantities of caffeinated beverages isn't a brilliant idea either..

[papsosouid]

As others have posted, scientific evidence shows no diuretic effect. You are peeing a lot because you are drinking a lot. You would have to pee just as much if you were drinking water.

[thejosh]

Placebo effect?

[trafficlight]

Because I think I'm drinking water but actually I was given the Mountain Dew cup?

[kyle4211]

I think the question implies the other way around?

[crusso]

Maybe it doesn't contribute to dehydration, but it sure does contribute to a lot of trips to the bathroom.

[jrockway]

Try drinking a few "Venti" glasses of water instead of coffee. You'll find yourself in the bathroom just as often.

[crusso]

Not true. I have gone off coffee and caffeine a couple of times over the last 6 or 7 years. When I drink a few cups of coffee, I'm up to the bathroom a half dozen times a day. When I switch to a water bottle, I only have to go maybe once per day (during work hours). The difference is stark and the amount of liquid is not the issue.

[jrockway]

So your body magically produces extra liquid when you drink coffee?

[crusso]

Is immature snarkiness really needed when someone is talking about a real physical effect carefully observed over years?

Caffeine gives me an urgency to urinate. Having that first urination in the morning after drinking coffee is just like the effect many people describe after drinking the beer. See "Breaking the seal".

Googling the subject shows confirmation from health and medical web sites. Here's one from the Mayo Clinic: http://www.mayoclinic.com/health/urinary-incontinence/DS0040...

[mh-]

I believe he was referring to the [frequency of the] sensation to void his bladder, not the resulting volume.