We've all been there, or at least thirty percent of coffee-drinkers have: you down your morning cup of joe and are halfway out the door when your stomach grumbles..and you suddenly have to poop.
What explains coffee's laxative effect? As a new video (above) from the American Chemical Society's "Reactions" series says, this poo-effect used to be chalked up to caffeine, which is a known laxative. But it turns out there's more to the story.
It seems that coffee causes the stomach to ramp up its production of gastric acid. This, in turn, can cause the stomach to quickly dump its contents into the intestines.
Other factors may contribute as well: coffee can induce rhythmic contractions in the intestines and raise levels of the hormones cholecystokinin and gastric, which kick-start the colon.
Talk about getting a jolt from your java!