Caffeine and hydration

Being one of the habitual consumers of Diet Coke on these forums, I've gotten feedback that caffeinated beverages really don't serve you well as they are diuretics. However, Googling "caffeine hydration" turns up quite a few hits that clearly state that there is really not a difference in hydration effects between caffeinated vs. Non-caffeinated beverages - at least for those who are regular consumers of caffeine. Has Jerry been right all this time?

I have the same habit of drinking way too much diet pop. Just yesterday, I had over 80 ounces of it throughout the day. I wouldn't say I have this much everyday, but on average, 44 ounces.

I will say that it can occasionally bother my stomach if I have too much. When I'm preparing for a marathon, I will lay off it for a few days prior.

Now hopefully, GregC will chime in on this. I know he's one that will also have his 44 ouncer the morning of any race he does.

Nancy Clarke posted on Hal's board that for a habitual caffeine drinker, there is no additional diurectic effect between 1 cup and 5 cups of coffee.

What Dave said. Personally, I feel the effects from booze a lot more than coffee. And I drink coffee pre/post run every day as well as a drink or two almost every night with/after dinner.

Caffeine has an affect on those who are not habitual caffeine drinkers. Otherwise, it doesn't really come into play that much.

I am quite different, thus my experience doesn't help. But since my name is mentioned:

I actually reduce my diet coke intake in the last week of marathon. I also stop drinking anything after last dinner, typically before 6:00pm.

Is the actual question being addressed?

diuretic [ˌdaɪjʊˈrɛtɪk] adj (Medicine / Pathology) acting to increase the flow of urine

n (Medicine / Pharmacology) a drug or agent that increases the flow of urine


I think any caffeinated drink, no matter how much you drink regularly, is a diuretic. I think some of the responses are addressing the slight dehydration effect that caffeine might have?

Tom, I wasn't referencing what you're drinking during the day, just suggesting you choose something non-caffeinated for re-hydration after you run. I drink boatloads of diet Mt. Dew, but I'm used to it. I also make sure I'm drinking water/G2 in the afternoon if I'm running that night to make sure hydration isn't an issue.

44 oz? I wish I only drank 44 oz. On an average day, I probably drink 8-10 diet cokes. I'm trying to mix G2 in there to cutback. So far, I'm up to 1.

I have 64 ounces of coffee most mornings and have not noticed any negative effects.

Randy E wrote:I have 64 ounces of coffee most mornings and have not noticed any negative effects.

Man Randy you drink a lot of coffee! Do you have to visit the bathroom often? I don't drink that much and the stuff just goes right through me!

I do not have to go as much as you would think. The funny thing is, one day I realized that 64 ounces is actually 8 eight ounce glasses of fluid first thing in the morning. A decent amount to start the day. Heck the daily recommended water consumption is 8 glasses per day for most people. I would bet that I consume at least an additional 64 ounces for well over 130 ounces of fluids per day.

I even drink that coffee before races. It really helps me eliminate pre race.

Tom H wrote:Being one of the habitual consumers of Diet Coke on these forums, I've gotten feedback that caffeinated beverages really don't serve you well as they are diuretics. However, Googling "caffeine hydration" turns up quite a few hits that clearly state that there is really not a difference in hydration effects between caffeinated vs. Non-caffeinated beverages - at least for those who are regular consumers of caffeine. Has Jerry been right all this time?

That is correct!

JohnP wrote:Is the actual question being addressed?

diuretic [ˌdaɪjʊˈrɛtɪk] adj (Medicine / Pathology) acting to increase the flow of urine

n (Medicine / Pharmacology) a drug or agent that increases the flow of urine


I think any caffeinated drink, no matter how much you drink regularly, is a diuretic. I think some of the responses are addressing the slight dehydration effect that caffeine might have?

John, Nancy Clark has stated on Hal's boards the the diurectic effect comes as the result of your first cup of coffee, and that there is no increased urination caused by cups 2 through 5.

She's the expert, so I'm just paraphrasing her advice.