Why Does Coffee Make You Poop

Are you one of the millions of people in the world who drink coffee? If you are, you may have noticed that your morning cup of coffee wakes up both your brain and your bowels. For some people, coffee brings on a quick trip to the bathroom. It's not clear exactly why this is, but studies are beginning to give some answers.

Why does your morning cup of coffee cause bowel movements?

There are several known reasons why coffee can make some people poop. Coffee has more than 1,000 different substances, and some may help stimulate your digestive tract. But it's not clear exactly which compounds have this effect. Here are a few explanations.

1. Caffeine stimulates your brain - and your gut

Most people drink coffee because the caffeine perks them up in the morning. Caffeine is considered a stimulant. But it doesn't just make you feel more clear-headed. It can also stimulate the muscles in your digestive tract. Caffeine increases motility (movement) in the colon, which helps move food toward the rectum.

But caffeine may have other effects. One study showed that caffeine relaxes the anal sphincter, which is the part of the body that keeps stool in or lets it out. This makes it easier to poop.

2. Coffee releases gastrin

The lining of your stomach makes a hormone called gastrin. Coffee sends a signal to your stomach to release gastrin. This kicks off a wave of contractions in your gut called peristalsis. Peristalsis moves food and liquid through the intestines. For some people, this leads to a bowel movement.

Caffeinated and decaf coffee both cause your stomach to release gastrin. The effect is less intense with decaf coffee, but it's still there.

3. Coffee triggers the gastrocolic reflex

The gastrocolic reflex is when muscles, nerves, and hormones work together to move solids and liquids through the intestines. When you eat or drink, this stimulates the gastrocolic reflex to move stool down toward your rectum.

Many things affect this reflex. Simply eating or drinking something, like coffee, can stimulate it. Also, the gastrocolic reflex is naturally more active in the morning. This may be part of the reason that a morning cup of coffee is more likely to make you poop than if you drink coffee at other times of the day.

Does decaf coffee also make you poop?

Yes, decaf can make you poop, though maybe not as much as regular coffee. For a long time, it was thought that caffeine was fully responsible for getting the intestines moving. But the gastrocolic reflex and coffee's effect on gastrin suggest that there's more at work than just caffeine. Caffeine seems to make a difference, but it's not the whole story.

Do different types of coffee drinks affect your body differently?

Coffee itself can make you have to poop. But the things you may add to coffee can also affect bowel movements. For example, dairy products like milk or cream can cause bloating, gas, and loose stool for people with lactose intolerance.

There are probably some small differences in the amount of caffeine and other components in different types of coffee like light roast, dark roast, and cold brew. So far, it doesn't seem like there's enough of a difference to cause a change in bowel movements for most people.

But some of us are sensitive to small changes in diet, so it helps to be aware of how your body reacts to different kinds of coffee.

Does coffee help with constipation?

It depends. For some people, coffee may help with a bowel movement. But you'll need more than that to keep you regular. Good bowel health requires a diet with plenty of fiber, regular exercise, and drinking enough fluids every day.

If you find that coffee helps you poop, you should only enjoy it from a cup. Coffee enemas are sometimes promoted as a way to treat or prevent different health conditions. But this use of coffee is risky and can damage your body.

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