Does Drinking Coffee Actually Dehydrate You Or Is This Just Another Myth?

There is a lot of debate over whether coffee is good or bad for health, but let’s just look at one aspect for now – does drinking coffee dehydrate you? This question is especially pertinent during summer, when the risk of dehydration is much higher.

Coffee has long been linked to dehydration because it contains caffeine and studies show that caffeine can have a diuretic effect, especially if it is consumed in sufficiently large amounts. However, recent research shows that we have misjudged coffee and that drinking coffee on a daily basis will not leave you parched!

Does Coffee Cause Dehydration?

“Coffee may be dehydrating to those not habituated to the drink, but for regular coffee drinkers the beverage can provide some amount of hydration!”

The basis for the idea that coffee causes dehydration can be traced to a study in which the researchers concluded that caffeine can increase urine output by as much as 50% (and thus lead to dehydration) – what most people overlook is that this study had just 3 participants and it was conducted in 1928!

However, more recent research shows that there is no difference in hydration levels between people who drink water or the same amount of coffee and therefore drinking coffee will not cause dehydration. This detailed study not only measured the volume of urine, but it also tested for hematological and urinary markers of hydration and kidney function and found that there were no significant differences between the participants that drank water and those that had coffee.

The findings of this study suggests that 4 cups of coffee will produce similar hydrating qualities to water in people who are habituated to caffeine.

How Much Coffee Should You Drink?

“If you are a habituated coffee drinker, you can drink up to 4 regular cups of coffee in a day – which is 1 liter of coffee!”

If you are not a regular coffee drinker and you suddenly decide to drink 2-3 cups at one go, it will affect you differently from a coffee addict! The large dose of caffeine would increase the blood flow to your kidneys and inhibit the absorption of sodium, which is why it would act as a diuretic and increase your urine output.

If you are not used to drinking coffee, start with just 1 cup a day. However, according to medical experts, if you are a habituated coffee drinker, you can drink up to 4 regular cups of coffee in a day – which is 1 liter of coffee!

Our Take

The science shows that drinking coffee will not increase your risk of dehydration, but this is only as long as you use a little common sense! The jury is still out on the health risks of coffee, so until there is a scientific consensus on the effects of coffee, it would be wise to limit your intake.

Although a cup of coffee has the same hydrating qualities as water, it also has other effects – the most embarrassing one being the laxative effect of caffeine.