Auto-Brewery Syndrome: Making Beer In Your Gut

Recently, there have been cases of people with blood alcohol concentrations at a level of .30 (nearly 4 times the legal limit) and higher when they have not consumed more than 2-3 drinks in a day, or even zero drinks that day. No it’s not because these people are hiding the truth or are chronic alcoholics – it is because they suffer from auto-brewery syndrome also known as gut-fermentation syndrome.

Auto-brewery syndrome is a condition where an individual generates ethanol inside their body by converting carbohydrate-rich foods into ethanol. How is this possible you ask? This happens when an individual possesses an overabundance of brewer’s yeast inside their gut. Brewer’s yeast, or Saccharomyces cerevisiae, is in a host of foods including breads, wines, and beers; some people even take Saccharomyces as a probiotic supplement. Usually, the yeasty creatures harmlessly pass through the individual’s system without incident; however, on occasion the yeast takes up residence in the intestinal tract of the individual and begins the ethanol production process. When this occurs, the yeast converts sugars in carbohydrate-rich foods into ethanol.

This was the case recently when a New York woman was arrested for Driving Under the Influence with a blood alcohol level of nearly .40. The woman met her husband at a restaurant for food and drinks earlier that day. Although the woman claimed to have only consumed 4 drinks between noon and 6 p.m., less than one drink per hour which should have produced a B.A.C. between .01 and .05 for her size and weight, her B.A.C. was not only well beyond the legal limit but was within the range considered to be life-threatening.

The woman was stopped when she was seen driving on a flat tire and another motorist called to report the situation as an auto accident. After a breathalyzer test registered such an extreme level of alcohol, police transported the woman to the hospital. Hospital staff recommended discharging the woman from their care because she was not displaying any symptoms of intoxication. Instead of letting his wife be released from medical care due to her lack of symptoms, the husband demanded that the hospital conduct tests to discover the cause of his wife’s condition.

During her medical evaluation the woman was observed for a 12-hour period and was not given anything containing alcohol. Curiously, at 9:15 a.m. the woman’s B.A.C. was double the legal limit, triple the limit at 6 p.m., and more than four times the legal limit at 8:30 p.m. Even more curious was the fact that the woman never displayed outward indications of intoxication during the evaluation until she reached a blood alcohol level between .30 and .40. Medical personnel determined that the woman was suffering from auto-brewery syndrome, and that she had been for such an extended length of time that she was the equivalent of a “functioning alcoholic.”

As a result of this evaluation, the Erie county judge dismissed the charges against the woman for driving under the influence. Because this condition is so rare there is little medical literature on it; however, if you are one of the few who know that you could not have possibly consumed enough alcohol to reach extreme levels of blood alcohol, you may want to talk to your doctor.