There are a lot of things our bodies do that we don’t tell them to — our lungs know to breathe, our hearts know to beat, and we can grow humans in our bellies — but before now, you might’ve thought brewing beer involuntarily would be an impossibility. It’s not, it’s called auto-brewery syndrome, and it means basically what its name implies: Your body brews beer in your stomach without you even having to invest in one of those home-brew kits that are all the rage with your brother-in-law who posts about it constantly on Facebook.

While this might at first seem kind of awesome and miraculous to the average beer drinker, the reality actually sounds a lot less fun. In the case of a 61-year-old man who yes, liked to do some home brewing, he only knew at first that he kept getting dizzy, reports NPR’s The Salt blog.

When he went to the ER to get to the bottom of things, nurses gave him a Breathalyzer test and figured he was just drunk because his blood alcohol concentration was at 0.37% — almost five times the legal limit. But he claimed he hadn’t sipped nary a drop of booze that day.

Some medical professionals thought maybe he was just drinking on the sly and claiming he didn’t have a problem.

“He would get drunk out of the blue — on a Sunday morning after being at church, or really, just anytime,” says the dean of nursing at the Texas hospital he visited. “His wife was so dismayed about it that she even bought a Breathalyzer.”

But she and a gastroenterologist wanted to track down the true source of his apparent self-drunkenness. So they locked him in a hospital room without liquor for 24 hours and checked his blood for alcohol while he ate a lot of carbs, noting his blood alcohol content all the way. It rose 0.12% at one point without drinking a drop.

The medical team finally traced it to an overabundance of brewer’s yeast in his gut. Which means his intestinal tract was acting like his very own internal craft brewery. Blood & Guts IPA, perhaps?

Turns out he was infected with a specific species of yeast (Saccharomyces cerevisiae), so that any time he drank or ate a lot of starch, the yeast would ferment the sugars into ethanol, getting him drunk. The medical professionals called it a case of “auto-brewery syndrome” in a recent issue of the International Journal of Clinical Medicine.

Before you get any ideas about supplementing your diet with this yeast so you can get drunk on the cheap, you should know that it’s probably not a great idea and also likely won’t happen to you. The yeast has to settle in and live in your gut for a while, and can cause other problems, notes a microbiologist at Duke University.

“Researchers have shown unequivocally that Saccharomyces can grow in the intestinal tract,” he told The Salt. “But it’s still unclear whether it’s associated with any disease” — or whether it could make someone drunk without drinking.

Basically, this kind of case is very rare and you shouldn’t try gut-brewing at home. Stick to the lagers and the pilsners that you’re used to.

Auto-Brewery Syndrome: Apparently, You Can Make Beer In Your Gut [The Salt]

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