Coffee makes you poop.
Wait, let me modify that statement: coffee makes some people poop, and it encourages others to poop (maybe not for the reasons you might guess).
The product used to make brewed coffee is commonly referred to as "coffee beans", so it would make sense that people would associate coffee's digestive effects with those of beans. As the classic ditty goes, "Beans, beans / Good for the heart / The more you eat them / The more you fart".
However, coffee doesn't actually come from beans; coffee beans are really coffee fruit seeds. So perhaps the other famed song celebrating beans' digestive effects ("Beans, beans / The magical fruit / The more you eat them / The more you toot") is closer to the truth! Whereas beans are known for inducing gas, though, coffee tends to cause people to actually poop.
Does coffee really make you poop?
Coffee can create an urgent need to poop for some people. For others, it brings on defecation in a more subtle way. It depends on your individual body chemistry, but there are some general guidelines for figuring out the odds of whether or not your number one drink will move your body to a quick number two.
Who does coffee make poop?
According to the leading study on the topic, coffee makes about 29 percent of the population need to poop soon after drinking. Nineteen percent of the men in the study needed to poop after drinking coffee, compared to over half the women in the study (53 percent to be exact).
So, coffee is way more likely to make women need to poop than to make men need to poop.
When does coffee make you poop?
Of the people in the study who said coffee made them poop, 52 percent said that coffee only made them poop in the morning. Similarly, 58 percent said that coffee only made them poop if they hadn't already pooped that day.
Those who were "moved" by coffee said that there was a span of about 20 minutes between drinking coffee and visiting the toilet.
Why does coffee make you poop?
The main documented reason for coffee making people poop has to do with a reaction in the distal colon, which is located at the end of the colon. The reasons for this are not well understood but are thought to have to do with a wide variety of hormonal effects based on the exorphins in coffee (which bind to opiate receptors) and two naturally occurring chemicals in coffee called Gastrin and Cholecystokinin. These chemicals are thought to be absorbed into the blood and directed to the brain and colon. Then, they are thought to stimulate muscle contractions in the lower colon, thus promoting bowel movements in the 20 minutes after coffee is consumed.
Additionally, coffee is high in magnesium, which can also make people poop. Some say that the caffeine in coffee makes you poop, but decaf coffee has been shown to be just as likely to make people poop as regular coffee.
How much does coffee make you poop?
According to one study, coffee makes you poop as much as you would after a 1000 kCal meal (that's 1000 "food calories", the calories you see listed on food packaging).
This is particularly amazing because coffee with no additives is calorie free.