Maulik D. Shah, DO, Gastroenterologist, Virtua GI & Digestive Health

Coffee: it wakes the soul, jumpstarts your day, and—for many—completely hijacks your bathroom schedule. It's like the moment you take that first glorious sip of java lava, your digestive system snaps to attention and says, "Oh, we're doing this now?"

So what's the deal? Why does coffee make you poop? Is it sorcery? Is it science? Is your colon just being super dramatic?

Sit back, relax, grab a seat (preferably near a toilet), and let's break down why your daily caffeine cocktail sends you speed-walking to the bathroom faster than you can say, "grande half-caf oat milk latte."

The Gut-Brain-Hot Beverage Connection

Your digestive system is honestly amazing. But it's also your body's most dramatic coworker: easily triggered, constantly reacting, and never subtle about what it wants. When you drink coffee, you're activating a mechanism called the gastrocolic reflex. This natural reflex signals your colon to make room—because breakfast is on the way.

Coffee cranks this reflex into overdrive. In fact, a 2021 Harvard Health study found that coffee boosts the hormones gastrin and cholecystokinin (CCK)—both of which directly activate the gastrocolic reflex.

So yes, it's a very real thing. A "cancel-your-meeting-and-find-a-bathroom" kind of thing.

It's More Than Caffeine, But It's Also the Caffeine

Caffeine stimulates the central nervous system, which can kick your digestive system into gear. It speeds up peristalsis—the wave-like muscle contractions that move food through your intestines. So, switch to decaf… right?

Well—and this is important—even decaf can have the same effect for some people. That’s because coffee contains more than just caffeine. Compounds like chlorogenic acids and N-methylpyridinium (formed during roasting) may also stimulate the gut.

So, either way, you're probably gonna poop.

Milk, Sugar, and Digestive Drama

Not to point fingers, but sometimes it’s not the coffee—it’s the stuff you put into it. That almond-coconut-oat-hazelnut hybrid creamer with 36 ingredients. That sugar-free, dairy-free syrup with a shelf life longer than the frozen pizza sitting in the back of your freezer.

A couple of things can happen when you start dressing up your coffee. For one, dairy can be a gut irritant if you're even slightly lactose intolerant—and many people are without realizing it. Sugar substitutes like sorbitol or erythritol, often found in “sugar-free” or “zero-sugar” creamers, can also cause bloating, cramping, or diarrhea in some people, especially when consumed in larger amounts. And those non-dairy creamers? They often contain additives, gums, and oils that might not sit well with sensitive stomachs.

So it's possible coffee isn't the problem, it's the entourage you might be bringing to the party.

Gut Check: Should You Be Concerned?

In most cases, pooping after coffee isn’t something to worry about—unless it’s interfering with your day. If you find yourself sprinting to the bathroom every morning, consider cutting back or eating something first. Giving your coffee a little tummy company can help tone down the urgency.

But if your coffee routine is causing daily distress, it might be time to check in with a specialist. The gut health experts at Virtua GI and Digestive Health can help you figure out what’s normal, what’s not, and how to keep your digestive system running smoothly—with or without caffeine.