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Can You Be Drunk Without Drinking?

Rarely, a person will act drunk but will deny drinking alcohol. Yet, a blood test for alcohol shows high levels! There is a scientific explanation for this curious phenomenon that has been termed auto-brewery syndrome.

It all started with a stomach exploding in Uganda. It’s the case that’s often cited as launching the saga of a fringe diagnosis: a five-year-old boy in 1946 was being treated for a chronic bacterial infection and he complained of abdominal pain. When surgeons operated, they discovered a significant tear in his stomach from which fluid and gas were pouring out. And there was a penetrating smell of alcohol. The child unfortunately did not survive.

Over the next decades, a number of cases were reported in Japan describing people who behaved as if they were drunk but who swore they had not touched a drop of alcohol.

If you were a police officer and you were pulling someone over for erratic driving, and they tested positive for alcohol but told you they had not consumed any, would you believe them?

Skeptics in the pub

It’s called auto-brewery syndrome (ABS) and has also been referred to as “gut fermentation”. The proposed cause of this syndrome is that yeast grows in parts of the digestive tract where it shouldn’t, and this yeast feasts on the sugars from the diet and turns these carbohydrates into alcohol. The alcohol enters the bloodstream and voilà: drunkenness without drinking.

In 1990, a paper published by the Biolab Medical Unit in the United Kingdom seemingly revealed that ABS was actually widespread. Researchers tested over 500 people suspected of having this condition (a bizarrely high number for a syndrome that had seemed up until then quite rare). They gave these subjects sugar, took a blood sample, and measured the alcohol content. 61% of these participants had an elevation in blood alcohol level after taking the sugar, and 69% of a control group of people who were just getting a standard glucose tolerance test were also positive. The authors of this paper concluded that ABS was “remarkably common amongst patients who are chronically unwell.”

But skepticism is warranted. The website of the Biolab Medical Unit, a laboratory which still exists at the same street address, shows a number of questionable medical tests being offered, like their ADHD panel, IgG food panel, and urine fluoride test. The technique used in their 1990 paper to detect blood alcohol was also criticized ten years later, and the numbers they reported were deemed to be theoretically impossible.

There was in fact quite a bit of skepticism vis-à-vis ABS in 2000. It was argued by some that the cases presented in the scientific literature had been poorly reported and that there was a risk of sample contamination when testing for alcohol content. Two women, who had invoked auto-brewery syndrome as a defence against driving under the influence, were asked to undergo proper testing. They declined and dropped their defence, which certainly looks fishy. A university science lecturer found himself in a similar situation but did undergo testing. It turns out, however, that the vials used for the blood draw did not contain a preservative (a no-no); that the vials were not properly taped to allow for a clear chain of custody; and that the man was allowed to hold on to his own samples for over an hour before giving them to an inexperienced analyst. If you were accused of drunk driving, with all the ramifications that a conviction implies, might you not try to fabricate an escape clause by invoking a questionable diagnosis and spiking your own samples? This is the argument that was put forth by skeptics back then who dismissed ABS as a fictional entity. In the past twenty years, however, newer investigations are giving credence to this diagnosis as they all point to one organ: the small intestine.

There’s trouble brewing

The food we eat enters our stomach and is broken down by enzymes. It then enters the small intestine, a long tube folded in on itself in the centre of our abdomen, where it undergoes further digestion, with nutrients and minerals crossing over to enter our bloodstream. Eventually, what is left enters the large intestine or colon, where water is absorbed and waste makes its way to the rectum. And it is in the small intestine that the story gets interesting.

A 13-year-old girl was suspected of abusing alcohol because of disorientation and a fruity odour on her breath. An elevated blood alcohol level sent her to a rehabilitation centre where, it is reported, she did not have access to alcohol but her inebriated behaviour continued and her blood alcohol levels remained high. Surgeons had removed parts of her small intestine when she was a newborn out of necessity, and when fluid from her small intestine was tested, the report came back positive for two species of yeast. There’s also a 71-year-old man who claimed to have abstained from alcohol for 30 years (his wife corroborated), who had similar symptoms, an elevated blood alcohol content, and who also tested positive for yeast in the small intestine. He had Crohn’s disease and had had parts of his small intestine removed. And what do we make of a three-year-old girl with short bowel syndrome walking erratically, whose parents could smell alcohol in her bedroom, who tested positive for many species of yeast and who was successfully treated with antifungals and a low-carb diet?

There are similar case reports of middle-aged men who developed this untimely inebriation following a course of antibiotics and who, when given a high-carb meal in the hospital, see their blood alcohol content spike. This last part is particularly important: these tests are now being conducted under observation to rule out surreptitious drinking. This is particularly important when accusing a yeast of making you drunk drive: the burden is on you to prove that you are one of the rare people with this affliction, but it is a defence that has worked in the past.

Conditions like auto-brewery syndrome are tricky because there’s a simpler explanation that begs to steal the spotlight: maybe these people drank alcohol and they’re lying. But given the many people tested in controlled environments with no obvious access to alcohol; given that almost all of them tested for species of yeast that should not be present in the small intestine; and given that these cases often report complete resolution after treatment without going through a substance abuse program, ABS is starting to look genuine, if rare (though possibly underdiagnosed). And while the idea of your body becoming the ultimate micro-brewery may sound clever, this condition is anything but fun. Before the condition is controlled, driving becomes a no-no, the risk for falls increases, and one patient was said to have lost 725 hours of work in sick time and disability time since the beginning of his ordeal. While many people enjoy getting tipsy on their own time, drunkenness loses its fun when it’s at the mercy of a yeast.

Take-home message:
-Auto-brewery syndrome is the name of a rare condition in which yeast present in the small intestine turns sugar from food into alcohol, making the person drunk without actually drinking alcohol.
-While there was skepticism about the existence of this condition early on, controlled testing of individuals in the past twenty years and the resolution of their symptoms with drugs that kill yeast and with a low-carbohydrate diet give plausibility to its existence


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