Why Does Coffee Make You Poop?

Coffee can make you poop. For more than 30% coffee drinkers, the brew has a strong laxative effect. But why?

Many people know first hand that a cup of coffee almost immediately means a trip to the bathroom. But what’s inside the cup that makes you want to go? ( (Photo: The Quint)

If you are a coffee lover you’ve been there. Besides the buzz you get from a cuppa joe, there’s another noticeable effect! The first sip of coffee and BAM! You gotta poop.

It is widely understood that coffee has a laxative effect on some people, what’s not so clear is why? Why on earth does coffee make you want to poop?

Here’s Why

About 30% people feel the need to defecate after drinking their morning joe. A number of studies have attempted to explain the effect of a cup of java on the bowels, scientists have yet to pin point an exact chemical which makes some people run to the loo.

One theory blames the excessive caffeine; a known diuretic, which means it makes you pee more than normal and also because ain’t it the mother of all health problems?

Caffeine is known to stimulate the gut, along with milk and sugar it puts additional pressure to cause contractions in the digestive tract muscles. But think about it - soda also has caffeine but that doesn’t have the same effect. Certain experiments have proved that people who drink decaf also feel the urge to poop.

If you have to rush to the loo after coffee, it’s perfectly normal. Coffee has that effect on roughly 1/3rd of java drinkers (Photo: The Quint)

So if coffee’s caffeine isn’t making you launch torpedoes, what is?

A second theory sees magnesium as the culprit. Coffee contains over 1000 chemicals and one of those is magnesium. One cuppa contains a solid 7 mg of magnesium, 10 times that amount is the recommended medical dosage of a laxative. So on a crazy day, if you OD on coffee, then blame the magnesium content for your bathroom trip!

Not all scientists agree that caffeine might be the laxative in coffee but people with irritable bowel syndrome (IBS) or irritable bowel disease (IBD) are usually more sensitive and should be cautious with coffee (Photo: iStock)

A study published in the medical journal Gut found that the acidity of the coffee is to be blamed - coffee has a compound called chlorogenic acid that triggers the release of hormones which speed up bowel movements. It could be that combined with dairy products and sweeteners, the overall acidity bump makes the stomach dump its contents out more quickly than usual.

Something in coffee may also trigger the release of hormones that aid digestion, which would speed up bowel movements. But it’s not clear which of the hundreds of chemicals found in a cup of coffee are responsible for that boost.

The result? You poop. And pretty quickly too. Scientists have found that the urge to poop comes as early as 4 minutes after drinking coffee. But if you don’t feel the urge after drinking coffee, then remember, the laxative effect occurs in only 30 or 40% of the population.

Bonus scientific finding - women are twice as likely to experience the coffee’s poop-ane effect!