Everything You Need to Know About Gut Fermentation Syndrome

Wouldn't it be fun if you could get drunk whenever you wanted, without even buying a beer? Well, unfortunately for people with gut fermentation syndrome, this scenario is their reality, and it's anything but fun. The science of gut fermentation syndrome is both a little confusing and a whole lot of fascinating. After all, what would having a brewery in your stomach even be like? Lucky for you, we've found out exactly what it's like and how it works, so you can answer that pesky question of, "What is gut fermentation syndrome?"

Gut fermentation syndrome is also called auto-brewery syndrome, and with good reason. To put things very simply, people who have this syndrome turn things they ingest into alcohol, without even trying, and it gets them drunk. Most people don't know they have it until something goes terrible wrong. And no, we're not just talking about someone writing on their face with a permanent marker.

This is nothing to be jealous of, but it is an unusual and interesting thing that happens to some people. So, unless you're one of those people, grab yourself a drink and read on for more facts about gut fermentation syndrome.


  • The Condition Is Exceedingly Rare

    The Condition Is Exceedingly Rare
    Photo: Toussaint Ruggeri / flickr / CC-BY-NC-ND 2.0

    You might wonder why you've never heard of auto-brewery syndrome before, especially considering how weird it sounds. That's because the condition is exceedingly rare. Just how rare are we talking here? The syndrome has only been recorded a handful of times, and we've only started actually researching it in the last few decades. In short, you're really, really unlikely to ever come across someone who has a severe case of it.

  • It All Starts with Gut Yeast

    So, what makes your digestive tract into a mini-brewery, anyway? The answer can be pretty complicated, and scientists still aren't completely sure if there's one single cause. What we do know, however, is that it generally has to do with yeast.

    Saccharomyces cerevisiae is a pretty common yeast in our everyday environment - it's known as "baker's yeast" or "brewer's yeast" because it is a common ingredient in bread and alcohol. It's usually pretty harmless, but if you have chronic health problems, especially involving the immune system, the yeast can overgrow in your stomach and intestines. So, whenever a person with gut fermentation syndrome eats or drinks, the overabundance of yeast in their gut takes all the sugars they've consumed and starts fermenting them into ethanol. Their body then absorbs it and, ta-da, their blood alcohol concentration start rising. Candida yeast has also been shown to cause gut fermentation syndrome.

  • Your Liver Might Be at Fault

    Your Liver Might Be at Fault
    Photo: Internet Archive Book Images / via Wikimedia Commons

    One of the reasons your gut yeast may be over-growing has to do with liver enzymes. Everyone has a little bit of yeast in their gut, and everyone creates minor amounts of alcohol, which the body processes. However, if your body doesn't process the alcohol and also creates too much of it, you might just have a secret, internal drinking problem. 

    In Japanese studies, people with gut fermentation syndrome all had abnormal liver enzymes, which meant they weren't correctly processing the alcohol they were creating. There have been other studies that question this research, but it's still a possible explanation.

  • It Can Get You Drunk... at Any Time

    This might sound like the fun part, but hear us out. Because your body is basically producing its own alcohol whenever you eat or drink, that means that everything you put into your body gets you drunk, and not in tiny amounts either. We're talking really drunk here. One simple meal can be enough to raise your blood alcohol level by 0.12 percent. Considering that the legally drunk blood alcohol level is anything above 0.08, that means that just eating breakfast can get you totally, uncontrollably, blackout levels of sloshed. Which is not particularly helpful when your boss takes you out for lunch, you have a burger and fries, and all of a sudden, you're slurring your words and trying very hard to make everything stop spinning.