Nothing beats cracking open a beer on a hot summer day—though, knocking one back on a cold winter’s day is pretty great too. But considering the reputation alcohol is earning as an evil substance that messes with your gut health, your finicky GI tract is probably wondering where your occasional cold ones fall on the spectrum.
The truth is, it’s hard to say. “Whether or not moderate alcohol consumption is beneficial for gut health is very controversial,” says Will Bulsiewicz, M.D., a board-certified gastroenterologist in Mount Pleasant, SC. “We currently don’t have studies examining the gut microbiome in mild to moderate alcohol consumption.”
Here’s what experts know so far about beer and the role it might play in your gut health:
“Beer does contain some important nutrients—namely, B vitamins and polyphenols,” says Bulsiewicz. Your digestive system relies on B vitamins to function properly, using them to break down and convert the nutrients from your grub—like carbs, protein, and fat—into energy. Meanwhile, polyphenols are thought to provide anti-inflammatory benefits to the body and may even have a prebiotic-like effect, stimulating the growth of good bacteria and putting bad bacteria on a tight leash.
Another potential perk: a University of California, Davis study found that beer contains soluble fiber, which is best known for slowing digestion and keeping the number two train running smoothly. There’s also evidence that consumption of beer may increase levels of one particular bacterial strain called—wait for it—bacteroides thetaiotaomicron (phew.) This bacteria munches on yeast mannans, a complex carb found in beer and bread, says Bulsiewicz, and produces something called short-chain fatty acids, which help promote a healthy gut.
“Although this is an area of lively debate, what we do know with certainty is that excessive alcohol consumption causes severe damage to the gut bacteria called dysbiosis,” says Bulsiewicz. Dysbiosis, or too much bad bacteria, is associated with oodles of medical conditions, such as autoimmune and neurologic diseases, and is thought to be a contributing factor in irritable bowel syndrome, says Niket Sonpal, M.D., assistant professor at Touro College of Osteopathic Medicine in New York.
Why? Alcohol acts as an irritant in the GI tract—among other things, it can reduce nutrient absorption, enhance toxin formation and transport, and increase gastric acid secretion (which can cause an uptick in reflux), says Edwina Clark, R.D., head of nutrition and editorial content at Raised Real. It’s also believed to relax the muscles of the colon, she says, which—combined with other factors—contributes to increased risk of diarrhea after a drinking episode.
Because there are so many variables that go into the production of beer—from the type of yeast, wheat, and barley used to varying fermentation times—research on which beers might be better for your gut is limited at this time, says Sonpal. However, it stands to reason that beers that are higher in polyphenols might be easier on the gut, due to the potential prebiotic perks they provide: “The general trend is for hoppier, more bitter beers to have higher concentrations of polyphenols,” says Bulsiewicz.
This is because the hops themselves—the plants used to add bitterness and flavor to beer during the brewing process—are driving both the bitterness and the polyphenol content. To find out how hoppy your go-to brew is, check out the IBU number on the label, which stands for International Bitterness Units—the higher the number (on a scale from 0 to 100), the hoppier the beer.
Clark also recommends opting for beers that are lower in alcohol to help minimize potential gut wreckage. And take note: Light beers aren’t necessarily lighter in alcohol—many have almost as much alcohol as regular beer, according to the National Institutes of Health, so make sure to check the label.
If drinking beer is messing with your microbiome, the symptoms will mimic that of a food sensitivity. Post-bevvy reflux, bloating, gas, diarrhea, and constipation are all key indicators that your GI system is out of whack, says Clark. Plus, recent studies have raised concerns that hangovers are caused by acute damage to the gut microbiota. “If consumption of beer makes you feel hungover, I would be concerned that damage has been done to your gut’s friendly inhabitants,” says Bulsiewicz.
Whether you’re combating a full-on hangover or minor uptick in gas, following up your suds fest with some gut-themed TLC might help even the score. “One study showed that probiotics may actually help to correct the damage done to the gut bacteria by alcohol,” says Bulsiewicz. Fermented foods (like cottage cheese, yogurt, pickles), prebiotic fiber (bananas, apples, asparagus), B vitamins (eggs, fish, whole-grain bread), and hydration are also important components of a gut restoration strategy.
Beer might not be the greatest for your gut health, but it doesn’t have to be the worst either. Things like drinking in moderation (up to one drink per day for women and two for men, with one beer clocking in at 12-fluid ounces), keeping tabs on your post-brewski symptoms, and establishing gut-friendly eating habits can go a long way in keeping your GI tract happy and healthy—sans deprivation.