He quit drinking in 2018 and got two DWI charges anyway, and the condition behind it has fewer than 100 documented cases

Mark Mongiardo, a 43-year-old from Florida, has spent years navigating life with auto-brewery syndrome, a rare medical condition in which the digestive system produces ethanol internally from the sugars a person consumes. As detailed by LADbible, he has not had a drink since 2018, yet he has faced two DWI charges in New York within a six-month period, including one that came a full year after he stopped drinking entirely. His case has drawn renewed attention to a condition that most people, including many medical professionals, have never encountered.

According to the Cleveland Clinic, auto-brewery syndrome has fewer than 100 documented cases on record, though researchers believe it is more widespread than current data reflects. It occurs when yeasts in the gut microbiome overgrow and begin fermenting carbohydrates and sugars into alcohol. If the body cannot process that ethanol efficiently, it enters the bloodstream and produces real symptoms of intoxication, regardless of whether the person has consumed any alcohol at all.

For Mark, the condition went unidentified for years. He worked as a teacher and athletic director, regularly chalking up his fatigue to long coaching days. Colleagues began commenting that he smelled of alcohol, and there were repeated instances where people around him noticed signs of intoxication he couldn’t account for. “I wasn’t aware that I may have been acting or showing signs and symptoms of someone intoxicated,” he told the New York Post.

His own body was working against him the entire time

The symptoms of auto-brewery syndrome mirror standard intoxication: slurred speech, loss of coordination, confusion, and elevated blood alcohol levels. For Mark, episodes were often triggered by carbohydrate-heavy meals, but even foods that appeared relatively normal could set them off.

Stress and poor sleep also played a role. He only received a formal diagnosis after undergoing a glucose challenge test at Richmond University Medical Center, during which his blood alcohol content reached 0.09 within 30 minutes and climbed to 0.14 during the test, all without consuming any alcohol.

By the time the diagnosis arrived, the damage had already accumulated. Mark had lost his job in education and was facing felony charges. He had to sell his house and his car, and his wife, who had been unaware of the condition, had spent years suspecting he was drinking in secret.

The two DWI charges were ultimately dropped due to prosecutorial delays. Amid a separate DHS official misconduct case drawing scrutiny this week over unreported conduct and its consequences for someone’s professional standing, Mark’s situation is a reminder of how quickly an unexplained medical condition can dismantle a career.

Managing the syndrome is ongoing and demanding. Mark follows a ketogenic, low-carb diet and avoids sugar, processed foods, and alcohol. He takes 30 pills daily, regularly uses a breathalyzer throughout the day, and is especially cautious before driving. During active episodes, which leave him severely nauseated, he is largely bedridden until his blood alcohol content returns to zero. Physicians generally treat the condition with antibiotics or antifungals to address the yeast overgrowth, followed by a long-term nutritional plan to limit fermentation.

In more severe cases, targeted probiotics or treatment for underlying metabolic conditions may be required. A Texas Ironman competitor who died after reportedly dismissing health warnings before entering the water earlier this week underscored how seriously the medical community has been pressing the message that physical warning signs should not be ignored.

The condition does not have a guaranteed permanent cure. If the underlying imbalance in the gut microbiome recurs, the syndrome can return, making prevention a long-term priority.

Doctors advise patients to maintain a varied whole-food diet, minimize sugar and starch intake, and be especially vigilant if they have risk factors such as diabetes, metabolic syndrome, or a history of frequent antibiotic use. Mark now lives in Florida with his family and works at Target, continuing to share his story publicly in hopes of raising awareness for others who may be experiencing unexplained symptoms without any diagnosis to explain them.