The Real Reason Coffee Makes You Poop

If your morning coffee lands you in the bathroom shortly after you've reached the bottom of your mug, you're not alone. In fact, having to go number two after a cup of joe is completely normal. Some people even use coffee to help keep them regular (via Medical News Today). "Caffeine acts as a hyper-mobility agent, meaning it promotes the movement of the gastrointestinal tract," says Lisa Ganjhu, D.O., a gastroenterologist at NYU Langone Health, told LiveStrong.

While not everyone experiences the same effect, and researchers have not agreed on a consensus on whether or not coffee really does lead to bowel movements, there are some studies that support that claim. According to Healthline, research has shown caffeine can activate contractions in the colon. The contractions push the colon's contents to the rectum, where it is then excreted from the body. A single cup of coffee contains about 95 grams of caffeine. But research also suggests decaf coffee can make people poop, too. That means other factors, like how certain compounds in the beverage interact with stomach acids, may also be at play. Coffee can also stimulate hormones that trigger bowel movements. One such hormone is gastrin, which, like caffeine, also activates the colon.

The effect of milk and cream

While coffee itself is naturally free of additives and preservatives, what you add to it might not be, and this can also trigger bowel movements. It's estimated that more than two-thirds of Americans add milk, cream, sugar, or artificial sweeteners to their coffee. Milk and cream in particular may make you poop, as they contain a sugar called lactose. According to MedlinePlus, about 65 percent of people around the world cannot fully digest lactose after infancy. People who are lactose intolerant experience uncomfortable symptoms like abdominal pain, bloating, and diarrhea after consuming dairy. So if you have any issues digesting lactose and add milk or cream to your coffee, it makes sense you'd need to poop shortly after.

While pooping after drinking coffee is normal, there are some signs to watch out for that may signal a health problem. Stool that is yellow, clay colored, or black, as well as blood in your stool are all reasons to see a doctor (via Penn Medicine). If diarrhea lasts for more than a few days, you should also call your doctor, as this might be a sign of an infection, food intolerance, or an issue with your digestive system.