Endogenous alcohol (EA) is ethanol that is produced naturally in all living humans. The resulting blood alcohol concentration (BAC) is generally low. But auto-brewery syndrome is linked with very high BACs. It occurs after eating meals rich in carbs.

Everyone has EA in their bloodstream. But auto-brewery syndrome is rare. Its origin is in the small bowel. There, very high levels of yeast convert carbs into ethanol. A type of yeast, Saccharomyces cerevisiae is  the major cause of this condition.

Auto-brewery syndrome is different from the usual fermentation in the large bowel. Normal yeast levels in the large bowel produce ordinary levels EA.

The Study

This study investigated the effect of diabetes, liver cirrhosis, and presence of both on BAC after eating a meal rich in carbs.

Studied were controls, those with diabetes, those with liver cirrhosis, and those with both diseases. After they consumed large quantities of carbs, their BAC was measured. The BAC of the controls was the lowest. The BAC of those with either diabetes or liver cirrhosis was much higher. The highest BAC was among those with both diseases.

Drivers with diabetes or liver cirrhosis should be aware that eating eating meals rich in carbs can increase their BAC. This is especially the case if they suffer from both diseases.

Note: Liver problems that prevent the body from breaking down alcohol normally can also cause high BAC without drinking.

Resources

Adams, C. Designated drunk: Can you get intoxicated without actually drinking alcohol? The Straight Dope.

Doucleff, M. Auto-Brewery Syndrome. NPR.

Geertinger, P., et al. Endogenous alcohol production by intestinal fermentation. Zeits fur Rech, 89(3), 167-172.

Kaji, H., et al. Intragastrointestinal alcohol fermentation syndrome. J Foren Sci Soc, 24(5), 461-471.

LaMotte, S. Woman claims her body brews alcohol, has DUI charge dismissed. CNN Health.

Logan, B. and Jones, A. Endogenous ethanol ‘auto-brewery syndrome’ as a drunk-driving defence challenge. Med Sci Law, 40(3), 206-215.

Thompson, H. The Man who gets drunk on chips. BBC.

Source

Hafez, E., et al. Auto-brewery syndrome: ethanol pseudo-toxicity in diabetic and hepatic patients. Hum. Exp. Toxicol.