Why Alcohol Gives You The Runs

Imagine this: You wake up at 1 p.m. on a Sunday afternoon. Your head hurts. You suddenly have a flashback to the night before. You see yourself sidled up to a bar, downing pickleback after pickleback until you yourself are turning green. You have some regrets. 

And then — just as you think the morning after effect can’t get worse — your stomach twists. You know it’s coming. You have the DADS — the Day After Drinking Shits. 

Tracy Lockwood Beckerman, RD, author of The Better Period Food Solution: Eat Your Way to a Lifetime of Healthier Cycles, explains that this is a common phenomenon. So common that there are even derogatory nicknames for it. DADS is a typical one, and then there’s rum bum, after grog bog, and, my personal favourite, the Milwaukee squirts. 

“The body doesn’t appreciate being distracted from other essential tasks — like keeping your heart beating or your brain working — to have to metabolise seven White Claws in an hour, so these choices may come with some unwarranted and smelly side effects,” Beckerman explains. Here are a few of them. 

As it turns out, in many ways! For some people, drinking makes your bowel movements more runny, but others will get more constipated. Everyone’s digestion system responds differently based on their genetics, diet, stress levels, and gut integrity, she explains. But most people can assume there will be at least some changes.  

“Alcohol has the capacity to affect the shape, form, and even the smell of your stool,” Beckerman explains. “Upon first sip, the body is trying to rid itself from alcohol ASAP.” With that said, not all poop problems after drinking are normal. If your irregular stool issues are persistent, you notice blood mixed in, or you have poop as black as the night, Beckerman recommends calling your doctor.

Alcohol is a gastrointestinal irritant and increases gut motility, explains Hillary Cecere, RDN of Eat Clean Bro. “Irritation to the intestinal lining can result in less absorption, leading to diarrhea or softer stools,” she says. 

Beckerman adds that alcohol has the ability to inhibit or temporarily “turn off” the antidiuretic hormone, or ADH, that tells our kidneys to conserve water. Without that hormone, you end up needing to urinate a lot, making you feel dehydrated and depleted in the morning. 

“During the act of drinking, you can have bouts of diarrhea due to the influx of fluids being dumped into the body,” she adds. “Plus, alcohol has the power to impair muscles movements in the GI tract which can propel contents faster through the gut, which can lead to diarrhea as well.” 

Beckerman says that some researchers believe that the higher the alcohol volume, the slower the movements in the bowel. Therefore, liquor (which is about 40 percent ABV) hits “the slow-mo button” on your poops, more so than beer or hard seltzer (which have about 5 percent ABV). “That’s why it’s more typical to have a sleepier and more sluggish colon in the morning — AKA constipation — with liquor,” Beckerman says.  

Cecere adds that you should avoid mixing alcohol with energy drinks because caffeine is also a GI tract irritant. 

Not exactly, Cecere says. “Chronic drinkers often suffer from GI distress due to alcohol induced inflammation,” she says. “But, it’s not uncommon for people who don’t often drink alcohol to experience digestive issues after drinking. Some people just consider it part of the hangover.”

There’s the obvious — drinking in moderation or not drinking at all. 

Beckerman also recommends eating a substantial meal before drinking. You could try rice, crackers, pasta, or some other hearty carb. “This can delay the absorption of alcohol into the blood, which can mitigate DADS,” she says. She also suggests introducing more probiotic foods — such as yogurt, kimchi, kombucha, or kefir — into your diet three or four days before drinking. 

“Drink water while drinking alcohol and take a multivitamin before drinking,” she adds. 

 “This will help rebalance your electrolytes and water soluble vitamins that have been compromised during your bender.”