Why Does Coffee Make You Poop?

Coffee gives people a boost in energy, but it might also boost their bowel movements too. Why is that? Well, in a study presented in 2019 at Digestive Disease Week, a team of Texas-based researchers documented the effects coffee had on the bowel movements of rats. What they learned is that it has little to do with caffeine, as the rats who were given decaf had similar results as those given full caf.

With the average American drinking two cups of coffee per day, that could mean there’s a lot of people hopping on the toilet post-java.

Why does coffee make you poop?

Coffee naturally contains hundreds of chemicals, so the answer to why does coffee make you poop is a little bit complicated, according to Kris Sollid, RD, the senior director of nutrition communications at the International Food and Information Council Foundation. People say the amount of caffeine in coffee could be one reason for an urge to poop after drinking a cup of java because it activates stomach muscles and the colon, but the study in rats seems to refute that.

“Hot beverages, in general, may also tend to have this effect, so a hot caffeinated beverage might be a double whammy,” says Monica Reinagel, MS, LDN, from NutritionOverEasy.com. Even though caffeine stimulates gut activity, it’s probably one of many reasons why coffee can trigger a bowel movement, Sollid says. Plus, drinking multiple cups a day makes this effect worse, and it’s one of the 7 signs you’re drinking too much coffee.

There’s a possibility that acidity plays a part too. Coffee contains chlorogenic acid and promotes the production of gastric acid in the body, according to Sollid. Both acids lower the pH of the stomach and speed up the movement of food from the stomach to our intestines, forcing the stomach to push out its contents faster than usual. Coffee also increases the production of hormones like gastrin and cholecystokinin that enhance the ability to digest food and activate the colon—which keeps things moving, Sollid says. Decaf coffee has a similar effect because it too impacts both gastric acid and gastrin, so the urge to go isn’t because of caffeine alone.

How to prevent the need to go?

Some research suggests regularly consuming coffee diminishes the effect. Reinagel couldn’t speak on the validity of that research but explains that people who regularly consume caffeine do develop a tolerance to its effects. “Coffee does not actually have any diuretic effect in regular coffee drinkers, for them, drinking coffee is equivalent to drinking plain water in terms of hydration,” says Reinagel.

And while the laxative effects of coffee occur with or without cream, dairy, and non-dairy milk, if you’re sensitive to dairy, adding them into your morning cup of joe definitely isn’t helping your stomach. So try drinking it black or with non-dairy creamer. If you want to take a walk on the wild side, try adding these 10 unexpected things to your daily cup of coffee.

So, why does coffee make you poop? Unfortunately, there’s really no definitive answer to this coffee-pooping conundrum; the only solution is to know your body and brew yourself that cup of coffee at your own risk. Sollid also recommends that if it’s a problem for you, you should discuss the issue with a specialist to check for possible underlying health issues. It is still possible to enjoy your morning cup of joe and be kind to your body, too, especially with these 11 ways to make your coffee habit healthier.