Beer gut: Man whose stomach produces alcohol cleared of drunk driving

A man in Belgium has been cleared of drunk-driving charges after it was discovered that he hadn't been drinking. Instead, his own body had produced the alcohol that tripped the breathalyzer test.

The 40-year-old man, whose named was not released by the court in Bruges, was pulled over in April of 2022, reports the New York Times, when he gave a breathalyzer reading of 0.91 mg of alcohol per litre of air exhaled. A month later, another breathalyzer test showed his breath contained 0.71 mg. Belgium's legal limit is 0.22 mg per litre, which corresponds to a blood-alcohol level of 0.5 grams per litre.

Three years earlier, the man had received a fine and a driving licence suspension after being pulled over, despite protesting that he had not drunk any alcohol.

After the latest incident, tests administered by doctors confirmed that the man has a rare condition known as auto-brewery syndrome, or ABS.

The condition causes carbohydrates in the stomach to be fermented, increasing ethanol levels in the blood. It can also result in signs of intoxication, although the judge emphasized that this was not the situation in this case.

The man's lawyer, Anse Ghesquiere, told the Guardian newspaper her client was happy to have his name cleared.

“I think he was somehow relieved that he finally knew what was up,” she said, adding that he is now on a strict diet and receiving medical treatment to manage the condition.

Ghesquiere did not name her client but said that he worked at a brewery, which she called “another unfortunate coincidence.”

Although ABS is extremely rare, it has been studied for some time. The website Medicalbag refers to a case in 2010 in which a 61-year-old was studied after suffering from years from unexplained ethanol intoxication, at one point even requiring a trip to a hospital emergency room.

It was found that his body contained high levels of Saccharomyces cerevisiae, better known as brewer's yeast and commonly used in baking, brewing and winemaking.