Why Does Drinking Coffee Always Make You Poop?
Gastroenterologists explain why you always run to the bathroom after your morning cup.
By Korin Miller Updated July 30, 2019
Listen, we've all been there: You chug down your morning cup of coffee and, within minutes, you're in a full-on sprint to the bathroom—and not for a quick pee. Like it or not, coffee poops are a thing, and while they're definitely not the hottest topic of conversation, you've got to admit: You are curious about why coffee makes you have to poop ASAP.
Unfortunately, there's no solid answer as to why coffee makes you poop—but there are some theories on the coffee-poop connection. "We don't know the mechanism completely, and there are only a couple of studies that have looked at this, says Kyle Staller, M.D., a gastroenterologist at Massachusetts General Hospital.
First: If you thought your sweet, sweet caffeine factored into your pooping schedule, think again. Dr. Staller points to an old study from 1990 in the journal Gut, that disproved caffeine's affect on your bowels when it found that both caffeinated and decaf coffee led to the same bathroom sprint. "That's not 100 percent surprising," says Dr. Staller, "because people who drink their favorite [caffeinated soda] don't have the same level of colonic movement afterward."
Also not a factor: The warmth of coffee (you don't have the same urge to go after sipping tea or soup, says Dr. Staller). The same goes for coffee's acidity, says Ashkan Farhadi, M.D., a gastroenterologist at MemorialCare Orange Coast Medical Center and director of MemorialCare Medical Group’s Digestive Disease Project in Fountain Valley, Calif. “You don’t have a similar effect after having something like orange juice,” he says.
So then why does coffee always make you have to poop?
Apparently, there’s just something about coffee as a whole that quickly stimulates receptors in your gastrointestinal system that causes your stomach and colon to contract, says Dr. Staller. (I know, it's not a terribly satisfying answer).
Those contractions happen in your body normally after you eat—it's called peristalsis, according to the U.S. National Library of Medicine, and it's a process of wave-like muscle contractions that move food to different processing stations in the digestive tract. With coffee, these contractions just seem to happen much, much faster. “It seems to happen as soon as four minutes after you drink coffee,” says Dr. Staller. “There’s no way the coffee itself made it to your colon in that time.”
The bad news? That means coffee can wreak havoc on your gut if you suffer from a condition that causes diarrhea, like irritable bowel syndrome (IBS-D). But there is an upside: If you struggle with constipation, having a coffee habit can actually help. In fact, Dr. Staller even prescribes taking their medication in the morning with their breakfast and coffee. “That’s a trick that we sometimes use,” he says. “You’re most likely to have a bowel movement when you wake up (because your colon wakes up), after you eat a meal, and when you drink coffee. Syncing those three things up gives you the best chance to get things going.”
Okay, but is there any way to stoppooping whenever you drink coffee?
Um, not really, says Dr. Farhadi. Since eating food also stimulates your colon, it's unlikely that drinking coffee with a meal will make a huge difference, if any. The same seems to be true for diluting the coffee, like with milk in a latte, says Dr. Staller.
But there is one you can do: If the whole pooping after coffee thing is truly irking you, you can try to find your limit by scaling back on the coffee until you find an amount that doesn't make you have to beeline to the bathroom. “It really is individual,” says Dr. Farhadi.
Overall, though, Dr. Farhadi recommends looking at your timely coffee poops as a good thing. “This can help keep you regular,” he says. “That’s a huge positive aspect of drinking coffee.” And honestly, a regular pooping schedule sounds like reason enough to grab another cup.