Florida man says he reeked of alcohol, but he wasn't drinking: Here's what was really happening

A Florida man spent years wondering why colleagues and coworkers questioned his alcohol consumption. He said he hadn't been drinking — especially with him working as a teacher and basketball coach — but was called into the principal's office on and off for several years. 

Mark Mongiardo, 40, told TODAY he worked more than 12 hours a day and credited his exhaustion and behavior changes to that. 

"I thought that there was something wrong with me. I wasn’t exactly sure what," Mongiardo, 40, of Florida, told TODAY.com. "I just thought I was tired all the time. My wife has on numerous occasions said I wasn’t acting right."

Mongiardo told TODAY he'd been arrested twice within six months for DWI even though he hadn't picked up a single drink. His wife began to worry that he was drinking in secret. 


After a couple of Google searches, Mongiardo and his wife believed they found a diagnosis — auto-brewery syndrome. 

"I had all the signs and symptoms of drinking even before she smelled me. So, for years, she thought I was hiding drinking and I would come home each day and I would basically be drunk," he told TODAY. "I had symptoms of being intoxicated from slurring speech to balance issues. And this happened even at social events where I had not been drinking."

Mongiardo struggled with finding employment due to the pending felony charges, so he had to sell his New Jersey home to move in with his wife's family in Long Island, NY. 

He finally found a doctor who was able to test him for the auto-brewery syndrome, which was turning the food he consumed into alcohol. 

As Mongiardo struggled to find work, he became a licensed real estate agent in New York and moved south to Florida before the pandemic hit. He told TODAY he monitors his BAC at home because he worries about driving with his children. 

What is auto-brewery syndrome? 

According to the National Insitute of Health, auto-syndrome is a gut fermentation syndrome condition in which ethanol is produced through fermentation by fungi or bacteria in the gastrointestinal system. Patients with auto-brewery syndrome present with many of the signs and symptoms of alcohol intoxication while denying an intake of alcohol and often report a high-sugar, high-carbohydrate diet.

The production of endogenous ethanol occurs in minute quantities as part of normal digestion, but when fermenting yeast or bacteria become pathogenic, extreme blood alcohol levels may result.