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Is Caffeine a Diuretic?

P.M. Willers
P.M. Willers

Caffeine is known to have a diuretic effect on many users, and some doctors even prescribe caffeine as a diuretic. Despite reports from patients and many in the medical community, scientific research has not been able to prove in an uncontested manner that caffeine can be classified as a diuretic. A diuretic is any substance or chemical that increases the production of urine by the kidneys. Besides caffeine, other common items that have diuretic properties or are natural diuretics include dandelion, fennel, nettles, and green tea.

Plants containing caffeine include coffee beans, tea leaves, and the kola nut, as well as dozens more. Caffeine can be found in the beans, leaves, nuts or seeds of a plant. Many individuals who drink coffee or tea report an increase in urination, and therefore consider the caffeine in these drinks to be a diuretic. The diuretic effects of caffeine vary according to the individual, taking into account diet, body composition, and daily caffeine intake. Research has shown that many individuals experience the diuretic effects of caffeine if they consume it after an extended period without caffeine.

Coffee, which contains caffeine.
Coffee, which contains caffeine.

Experts suggest that drinking three or fewer cups of a caffeinated beverage reduces or entirely eliminates the diuretic effects of caffeine. Specifically, the results of a number of studies agree that the caffeine threshold is approximately 300-360 milligrams of caffeine. Those who consume more than 360 milligrams of caffeine are much more likely to be affected by the diuretic properties of caffeine. It is important to note that individuals who consume a large amount of caffeine on a daily basis are able to develop an increased tolerance to the effects of caffeine.

An energy drink containing caffeine.
An energy drink containing caffeine.

The diuretic effects of caffeine may be more complex than simply the consumption of caffeine. Effects may be dependent on the type of beverages or food in which caffeine is consumed. For example, few people consider caffeine a diuretic when consuming dark chocolate.

It has also been proposed that any warm beverage may have a diuretic effect. This theory could be the source of many misconceptions about the properties of caffeine as a diuretic. Furthermore, many people are more likely to experience diuretic effects when consuming caffeine in coffee rather than soda. The best way to find out if you should consider caffeine a diuretic is to limit your caffeine intake and note changes in your body and body systems when the amount of caffeine you consume is increased.

Discussion Comments


I heard a doctor on TV say that caffeine removes water from our cells and causes it to get thrown out via urine. But soon afterward, I saw a study which said that caffeine is no more diuretic than water, so I'm very confused.

Maybe the diuretic effects of caffeine depends on the amount of caffeine and the tolerance level of the individual. For example, my roommate and I drink the same amount of coffee everyday. But she doesn't drink as much water as I do. I personally feel extremely parched after caffeine.

The other thing is that the form of caffeine matters too. I feel very thirsty after coffee, but not after having chocolate.


@ZipLine-- I'm not sure what you mean. I don't think that caffeine is diuretic like a prescription medication. But it definitely has a diuretic effect. I personally have to go to the bathroom more frequently when I drink a lot of coffee.


I don't think that caffeine increases the production of urine. I think it just speeds up the process. So we are not excreting more water than we would normally, it just happens in a shorter time frame. It causes more frequent urination which makes us feel that we are excreting more urine.

So caffeine does have a diuretic effect because it reduces water volume in the body. But it's temporary, it doesn't work for a long period of time because we feel more thirsty after taking caffeine. So I don't think that it's a good way to reduce water retention.

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    • Coffee, which contains caffeine.
      By: Designer_Andrea
      Coffee, which contains caffeine.
    • An energy drink containing caffeine.
      By: lecostaloca
      An energy drink containing caffeine.
    • The Chinese have used green tea as a natural diuretic for centuries.
      By: NataliTerr
      The Chinese have used green tea as a natural diuretic for centuries.