A 39-year-old man causes a head-on collision. Afterwards it turns out that he had four times the permitted amount of alcohol in his blood. The man said he had not had anything to drink and the judge acquitted him. How is that possible? Gastroenterologist in training and researcher Stijn Meijnikman explains. “Normal people produce about a glass of beer a day.”
“This example can certainly be correct. It was already described in one of the largest scientific journals worldwide, in 1894,” Meijnikman begins in WNL Op Zondag. “The first cases were discussed that people could auto-intoxicate themselves. In the past, people always thought it was fungi, but we now know that the bacteria in our intestines can very quickly turn sugar into alcohol.”
According to the doctor, this happens to almost everyone. “The intestines contain enzymes that can produce alcohol, but can also absorb it. They also use that as a breeding ground. Sometimes things go wrong and people have a lot of bacteria that can produce a lot of alcohol and do nothing other than that. Then there are indeed cases where people, for example after a carbohydrate-rich meal, get behind the wheel, hit a tree and then accidentally have a lot of alcohol in their blood.”
The phenomenon is called autobrewery syndrome and can therefore lead to extreme amounts of alcohol in the body, without anyone drinking. “There are people, as we have also shown in our research, who can produce up to a bottle of whiskey per day. These are really very special cases.”
Glass of bees per day
For most people it is limited to small amounts. “In normal humans, about a beer or a glass of wine is produced in the intestines per day,” says Meijnikman. “You don’t notice anything about it. Even if it increases, it goes through a vein to the liver and that is our protector. You cannot live without the liver. If that goes wrong, it actually stops. The liver clears all that alcohol and you therefore pick up almost nothing.”
Yet the effect on the liver can be significant. “If the liver consumes alcohol, almost all processes that also take place in the liver stop. Then alcohol breakdown is given preference,” he explains. “People who are obese, seriously overweight and people with fatty liver disease are given more alcohol. This often clears the liver just fine, but it does become fatty and it also causes inflammation and scarring. That causes a lot of damage.”
Alcohol drinking mouse
Another study, conducted in the American state of Virginia, shows how great the influence of intestinal bacteria can be. “If you transplant poop from a human who drinks way too much alcohol to a mouse, the mouse will start consuming alcohol, while mice don’t like alcohol at all. Isn’t that scary?” says Meijnikman.
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In extreme cases, a person can produce a bottle of whiskey worth of alcohol per day, says gastroenterologist Stijn Meijnikman. “They are bacteria in our intestines that can quickly turn sugar into alcohol. This happens to almost everyone, but you don’t notice it. Even if it increases,… pic.twitter.com/bTjO2xBFA7
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His colleague Marcel Levi, also present in the broadcast, adds: “It sounds very exotic, but what you actually do is that you replace the intestinal bacterial colony of one person with that of another. The simplest way to do that – it really happens in medical practice in serious infectious diseases or in a number of exceptional situations – is to collect feces from a healthy person, make a preparation and let it end up through a tube into someone else’s intestine. That is ultimately the research that Stijn has done in a lot of different ways.”
Yin en yang
Meijnikman emphasizes that auto-intoxication is rare, but that the consequences can be serious. “It’s terrifying that people who have one autobrewery syndrome have had it, have been successfully treated for it, then start consuming alcohol themselves even though they were not drinking before. It’s kind of yin and yang. There is so much to say about alcohol, intestines and the brain.”
He hasn’t drank for years. “We know that one glass of alcohol a day is actually one too many. I do science, am a medical specialist in training, have a young family and work a lot. I noticed that even if I drank just one glass, I had a heavy head the next morning. The advice now is simply not to drink alcohol. That is the healthiest for your entire body.”
