Why Does Coffee Make You Poop?

iStock/Photo illustration by Lauren Spinelli
iStock/Photo illustration by Lauren Spinelli

Coffee can give you more than just a caffeine buzz. For a large number of people—about one-third of the population—it also prompts a run for the bathroom. While this effect is widely documented, scientists aren’t exactly sure what’s behind it.

“It’s widely understood that coffee has a laxative effect on some people,” the American Chemical Society’s Reactions series noted in a 2015 video, but it’s complicated to tease out which part of coffee causes it.

It’s not just the caffeine, because decaf coffee can inspire the same, um, urgency. And people don’t run to the bathroom immediately after swilling a Coke. So what's happening inside your gut that makes you bolt for the commode just after finishing your morning cup o' joe?

Coffee has been found to stimulate your large intestine within just four minutes of ingestion, and drinking it increases the levels of certain digestive hormones in the gut. Coffee's laxative properties might also have something to do with its acidity, which helps your stomach produce more gastric acid to break down proteins. A compound in coffee called chlorogenic acid boosts stomach acid levels. This applies whether your coffee is caffeinated or not. As a 1986 study found, both decaf and regular coffee cause significant stimulation of gastric acid. (Both may also promote acid reflux, unfortunately, though the research is a bit contradictory.)

But that doesn’t mean all coffees are alike when it comes to spurring an increase in stomach acid. Research presented to the American Chemical Society in 2010 found that N-methylpyridinium, a chemical compound created in the roasting process, blocks the stomach’s ability to produce acid, meaning that dark-roasted coffees might actually be a bit easier on irritable stomachs than light-roasted varieties.

Some studies have found that coffee can accelerate gastric emptying—meaning the rate it takes for your stomach contents to empty into the small intestine—but this, too, is controversial, and some studies say coffee doesn’t impact gastric emptying at all. Since coffee only makes a portion of the population poop, though, it might just be that smaller studies (one only looked at 12 individuals) happen to not include any people whose bowels are really affected by coffee.

But the fact of the matter is, of the many chemical compounds contained in coffee, scientists aren't entirely sure which one is the poop perpetrator.

Poop is not just a byproduct of coffee drinking, either. Sometimes, it’s a vital part of the production process. Civet coffee, or kopi luwak, is known as one of the most expensive coffees in the world. It’s made from partially digested beans harvested from the feces of a civet. Because the beans have already passed through one stomach (the animal’s), the resulting coffee is much less acidic, meaning it’s a much smoother tasting—and feeling—experience for the humans who later drink the civet’s castoffs.

If you’re one of the many people whose coffee habits land them in the bathroom, know that all that post-brew pooping might not be a bad thing. Studies find that most people in the U.S. don’t eat enough fiber in their diet, so it may be a blessing that the average American drinks three cups of coffee a day. Otherwise, they’d have to change it to “land of the free and home of the blocked.”

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Why You're Probably Washing Your Hands All Wrong

Washing your hands is the best protection against germs.
Washing your hands is the best protection against germs.
rclassenlayouts/iStock via Getty Images

When some of us fall ill, we begin to wonder what brought on the coughing, sneezing, and aching. We might blame a sniffling person in the checkout lane or an office pandemic.

Obviously, there are many ways to catch a viral or bacterial infection. But the single best way to minimize that risk is to wash your hands. And while that might seem simple—it is, after all, a skill taught to us as children—you may not be doing it correctly.

Popular Science recently highlighted the importance of handwashing, noting that people may touch their face up to 52 times per day. If they’ve just touched a surface that’s harboring germs, that’s 52 opportunities for pathogens to settle in the mucus membranes and lash out with everything from flu to respiratory infections. Proper hand hygiene, according to the Centers for Disease Control, can reduce the community risk for respiratory illness by 16 to 21 percent and for unpleasantness like diarrhea by up to 40 percent.

The problem? People tend to wash too quickly, sticking their hands under the faucet for a few fleeting moments and moving on. In 2018, the U.S. Department of Agriculture evaluated 383 subjects and found that most did only a cursory wash.

It’s better to follow the CDC’s advice, which is to get your hands thoroughly wet with very warm water—which can be enough to kill some microbes—and then lather up, making sure to reach every fold and surface area between your fingers, around your wrists, and under your nails.

So far, this is not the stuff of surgical scrubbing. But here’s where most people drop the ball: Rather than soap up for just a few seconds, try to keep the cleaning going for 20 seconds. That’s two cycles of the “Happy Birthday” song. When you’re done, dry with a clean towel.

It’s good to wash up before eating, after coming from outside, handling an animal, or prior to touching your face for any reason, like putting in contacts or flossing. Obviously, washing after using the bathroom is a must, but you knew that.

As for hand sanitizer: It’s good for when there’s no running water available, but it can’t kill all germs, and it won’t do a whole lot if there’s visible dirt or grime on your hands. Water and soap remain the gold standard.

[h/t Popular Science]

China's Coronavirus App Is Alerting Citizens When They're in Danger of Being Infected

Coronavirus fears have spread throughout China and beyond.
Coronavirus fears have spread throughout China and beyond.
Kevin Frayer, Getty Images

Questions continue to linger around the new coronavirus, currently plaguing parts of China and other countries. In an effort to combat the spread of the virus, the Chinese government recently introduced a smartphone app that claims to alert users when someone suspected of having the virus has been nearby.

According to the BBC, the app, dubbed the “close contact detector," works by having phone users register their name and government ID number. Once they activate the service, they’ll be notified if they’ve been in a place where someone diagnosed with coronavirus has been. Patient A, for example, might have reported being on a train, in a classroom, or in an office space that the app user also occupied. The user would get an alert along with a notice to stay home in the event they might have contracted the virus.

Whether a user has been in close contact is determined by their physical proximity to someone suspected of having the virus. Airplane passengers in the three rows surrounding someone suspected of being infected would be considered in close contact. Other passengers may not be considered close.

The scope of the app appears to be limited to information provided by transit authorities and other institutions and does not appear to be an all-inclusive method of determining exposure.

The app is state-sponsored and was developed by the General Office of the State Council, the National Health Commission, and the China Electronics Technology Group Corporation. While critics have said the app presents an invasion of privacy and a way for government to track any user's movements, others have argued that the risk to public health warrants it.

"In this case the public good and the public health has to outweigh the privacy concerns, otherwise we have no shot of doing anything about this," Dr. Irwin Redlener, the director of the National Center for Disaster Preparedness at Columbia University, told ABC News.

[h/t BBC]

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