How Alcohol Affects Your Poop

After downing cocktail after cocktail during a night out, you may wake up needing a tall glass of water, ibuprofen, and a long visit with the porcelain throne. While bar hopping with friends, you might even need to set down your third beer and rush to the grimy bathroom to deal with a sudden, unexpected BM.

It may feel embarrassing, but don’t worry — you’re not alone in your struggles. “Alcohol definitely makes you poop — it’s no surprise,” said Dr. Sunana Sohi, a board-certified gastroenterologist with Gastroenterology Health Partners in Louisville. Kentucky. “It’s the body’s normal reaction to alcohol.”

Here, GI experts break down exactly why alcohol can trigger diarrhea, fecal urgency and other unpleasant side effects and the steps you can take to prevent them.

If your adult beverages are leaving your digestive system in distress, there’s one simple explanation: Alcohol is an irritant to the GI system, and it can inflame the lining of the digestive tract, from the esophagus to the large intestine, explained Dr. James H. Tabibian, a board-certified gastroenterologist at Adventist Health in Glendale, California. “This, in turn, disrupts the normal functions of the GI system, which regulate bowel movement production,” he added.

Specifically, alcohol increases gut motility, or how fast contents move through your gastrointestinal system, Sohi explained. Since your body is trying to remove the alcohol quickly, the colon — which is responsible for pulling water out of the digestive tract and reabsorbing it in the body to prevent dehydration — doesn’t have enough time to do its job, added Dr. Lauren Bleich, a board-certified gastroenterologist with Gastro Health in Acton, Massachusetts.

With more liquid in the large intestine and increased motility, you may end up with softer, more urgent stools, according to the experts. “If the body’s trying to go super fast and eliminate this toxin, it’ll just dump, and so you’ll see loose stools,” Bleich added.

How quickly you feel the urge to use the restroom while drinking — or if your bowel movements change at all — varies from person to person, according to the experts. “No one’s body reads like a textbook,” Bleich said. “It can be an hour or so later … but it can sometimes be the next day.” Still, folks with chronic gastrointestinal conditions such as irritable bowel syndrome, inflammatory bowel disease or celiac disease may experience symptoms in a more heightened and urgent way, Sohi added.

While soft stool and diarrhea are the most commonly experienced GI side effects, some individuals may suffer from constipation after a night of drinking, according to the experts. Alcohol suppresses the secretion of vasopressin, a hormone that regulates the body’s ability to retain water, Sohi said. Specifically, the hormone decreases water excretion by the kidneys and increases water reabsorption, leading to antidiuretic effects. “That [suppression] is why people will pee more when they drink,” Sohi explained. For the folks who feel backed up after a wine night, “the alcohol is making them pee out all the water in their body, and so they get dehydrated and then constipated because of it.”

With chronic alcohol use comes additional, often more severe, GI effects. “Alcohol can alter the balance of intestinal bacteria and lead potentially to bacterial proliferation, or overgrowth, which can cause diarrhea, as well as other symptoms like bloating,” Tabibian said. This bacterial imbalance (known as intestinal dysbiosis) is generally the result of chronic, frequent alcohol use, though occasional drinking can cause some temporary changes, too, he explained.

Drinking frequently can also cause permanent damage to the digestive tract, which can lead to frequent bouts of diarrhea, Sohi said. Chronic pancreatitis is possible; the condition inhibits your ability to absorb nutrients (particularly fat) and can cause chronic diarrhea, she noted. Of course, excessive alcohol use can lead to a host of other health problems, too, including cancer, high blood pressure, heart disease, stroke and liver disease, among others.

The amount of alcohol that triggers a need to go No. 2 is unique to the individual. “People’s guts are sensitive to different extents,” Bleich added. “So one person can have one or two drinks and notice this, whereas another person may require three or four to notice an impact or change in their bowels.”

There aren’t any rigorous studies investigating whether the type of alcohol consumed influences the symptoms you experience. But, theoretically, it could make a difference, Tabibian said. Wheat beer, for instance, generally contains more carbohydrates than hard spirits, and those carbs could increase the odds the drinker experiences loose stool or bloating, he explained.

Your game plan to ease alcohol’s impact on your bowel movements is relatively the same as your approach to preventing a hangover: Eat while you’re drinking, imbibe in moderation, stay on top of your water intake, and alternate between alcoholic and non-alcoholic beverages, Bleich advised. It may give you a feel-good buzz, but downing a handful of cocktails while on an empty stomach is also going to increase your risk of experiencing diarrhea, as your body is able to process the irritating alcohol even more quickly, Sohi added.

“There are anecdotal things, like [the belief that] eating more greasy food or fried food may slow down that stomach digestive process so you don’t purge as quickly, but a lot of people nowadays have a lot of issues with higher fat content,” Bleich said. “And there are a whole host of [health] reasons why you shouldn’t eat [fried foods], so it doesn’t necessarily work for people.” Not to mention, dietary fats have been found to trigger symptoms related to indigestion, including nausea, pain and bloating. Instead, nosh on a well-balanced, fiber-rich meal — which will slow the absorption of alcohol — before you hit the bars, Bleich suggested.

From the comfort of your own home (and bathroom), test out different alcohols and notice how they affect your digestive system. If you usually develop diarrhea after drinking regular beer, try a light beer with fewer carbohydrates and take note of how it makes you feel. “People might want to pay attention to what type of alcohol irritates their stomach,” Sohi said. “It’s not necessarily how much you drink that’s a contributing factor than it is the type of drink.”

The uncomfortable GI side effects of alcohol shouldn’t necessarily dissuade you from a night of casual drinking. But it’s important to understand what, exactly, is happening within your digestive system when you enjoy a few glasses of wine — and to know when to sip on some water instead.

“It’s a balance,” Sohi said. “You have to find that point where you’re not causing yourself harm. A little bit here and there is probably not going to cause you significant harm, but if you’re having girls’ night every night by yourself in your basement, it might become a problem for you.”