Auto-Brewery Syndrome: The gut disorder that gets you drunk!

Ever woken up feeling tipsy, dizzy, or foggy — without touching a single drop of alcohol? Sounds like a wild night you can’t remember, right? But for some people, this bizarre feeling isn’t the aftermath of a party. It’s actually a rare condition called Auto-Brewery Syndrome (ABS) — and yes, it's as strange as it sounds.

Imagine your gut turning into a mini brewery, fermenting food into alcohol and flooding your bloodstream with it. Sounds like science fiction? It’s not. It’s real, and it’s throwing doctors — and patients — for a loop.

What is Auto-Brewery Syndrome?
Auto-Brewery Syndrome, also known as gut fermentation syndrome, is a rare medical condition where your digestive system starts producing ethanol (the same alcohol found in beer and wine) from the carbohydrates you eat. Instead of breaking down carbs the normal way, certain yeast or bacteria in your gut go rogue and start fermenting those sugars, turning your intestines into an unlicensed brewery.

The result? You can actually get drunk without drinking alcohol. And we’re not talking just a little lightheaded — some people with ABS have blown over the legal blood alcohol limit without ever having a drink.

What causes it?
The main culprits behind ABS are usually strains of yeast — most commonly Saccharomyces cerevisiae (aka baker’s or brewer’s yeast) and Candida species. These yeasts are normally harmless and even helpful in small amounts. But under certain conditions — like after a course of antibiotics that wipe out your good gut bacteria — yeast can overgrow and take over the gut environment.

Once these microbes have free reign and access to carbs, they start fermenting food into alcohol right inside your body. It's like feeding sugar to yeast in a beer vat — but it’s happening in your intestines.

Who gets it?
Auto-Brewery Syndrome is rare, but it doesn’t discriminate. It’s been found in both adults and children. However, it's more often seen in people who:

• Have had frequent antibiotic use (which can disrupt gut flora)
• Have gut imbalances or chronic conditions like Crohn’s or diabetes
• Eat a high-carbohydrate diet
• Have weakened immune system

The syndrome often goes undiagnosed or misdiagnosed for years. Many patients are mistaken for alcoholics or accused of drinking secretly because their blood alcohol levels are high — even when they swear they haven’t touched a drop.

Symptoms: It’s not just “feeling drunk”
While the most headline-worthy symptom is spontaneous drunkenness, ABS comes with a laundry list of weird and confusing symptoms:

• Dizziness or disorientation
• Slurred speech
• Brain fog or confusion
• Fatigue
• Mood changes — including depression or irritability
• Bloating or gas (hello, fermentation!)
• Headaches or nausea
• Trouble concentrating

People with ABS may experience symptoms at random, especially after meals rich in carbs or sugar.

How is it diagnosed?
Diagnosing Auto-Brewery Syndrome can be tricky — mostly because it’s so rare and not on most doctors’ radars. If you suspect it, the first step is tracking your symptoms and eating patterns. Blood and breath alcohol tests taken without alcohol consumption can show elevated levels of ethanol.

Sometimes, a glucose challenge test is used. You basically eat a bunch of sugar and your blood alcohol is monitored afterward. If it spikes, bingo — you’ve got fermentation going on in your gut.

Auto-Brewery Syndrome might sound quirky or even funny at first — “drunk without drinking!” — but for people living with it, it’s anything but amusing. It can affect relationships, jobs, mental health, and quality of life. Imagine trying to convince your doctor, boss, or even family that you’re not secretly drinking when your blood alcohol level says otherwise.

So next time someone says, “I swear I didn’t drink anything,” maybe… just maybe… they’re telling the truth.

Want to keep your gut in check and avoid unexpected fermentation? Eat balanced, limit unnecessary antibiotics, and take care of your microbiome. Because the last thing anyone wants is their belly turning into a brewery.