Your alarm goes off, you roll out of bed, and the first thing you do is stumble into the kitchen to get your morning pot of coffee brewing. After a cup or two, my guess is you sit down and have a nice, relaxing few minutes on the toilet while you—ahem—relieve your bowels.

chocolate, mocha, milk, espresso, cappuccino, coffee
Ruby Siegel

While that morning dump certainly isn’t a bad thing, it does seem a bit strange that coffee makes many people poop. Though only 30-40% of coffee drinkers feel the urge to defecate after enjoying their morning brew, it’s enough to make me wonder why exactly that happens.

Many believe it’s the high caffeine content in coffee that causes extra bowel movements. Caffeine stimulates the vagus nerve (part of your central nervous system), which controls the digestive tract. It’s thought that stimulation of the nerve also stimulates digestion.

sweet, mocha, cappuccino, chocolate, espresso, cereal, coffee
Helena Lin

Caffeine also contains theophylline and xanthine, which stimulate the colon. They create contractions in your gut, which gradually pushes your poop closer to the rectum (lovely mental image, I know). However, it’s not the caffeine alone that makes you poop. It’s the combination of caffeine and xanthine that makes you go #2.

While many agree that caffeine is the main reason coffee makes you poop, others argue that it’s the acidity in coffee that actually encourages bowel movements. Coffee contains chlorogenic acid, which triggers increased stomach acid levels and a higher production of gastric acid. It’s thought that the increased acidity makes the stomach digest its contents more quickly. cream, mocha, espresso, milk, cappuccino, coffee
Gabby Phi

Other researches say your colon is more active in the morning in general because of your body’s circadian rhythms. So your cup of coffee might not actually be affecting your bowels in a particular way, you just happen to poop more often in the morning because you’re waking up, eating breakfast, and moving around.

Whatever the reasons coffee makes you poop, I don’t anticipate anyone giving it up any time soon. If you’re bored with your usual brew, try mixing things up with a cereal milk latte. Best of luck managing that caffeine addiction, friends.