Does Mr. Przybyla’s claim to law enforcement have any merit? Incredible as it may seem, possibly. He would need to be tested for gut fermentation syndrome or auto-brewery syndrome. The underlying mechanism is thought to be an overgrowth of yeast in the gut whereby the yeast ferments carbohydrates into ethanol. According to gastroenterologist Dr. Justin McCarthy a person can experience a set of circumstances that allows alcohol to be fermented within his/her own stomach and intestines. Scott, Medical Oddities Part 2: You can brew beer in your digestive tract, Today I Found Out, http://www.todayifoundout.com/index.php/2013/10/can-brew-beer-stomach/ In all of the known cases, some type of yeast (Saccharomyces cerecisiae, or brewer’s yeast) ferments the sugars coming from carbohydrates or any sugary foods into ethanol (ethyl alcohol). Should enough ethanol be produced, you get drunk. Id.
Brewer’s yeast is found in many different types of foods like breads, wine, and beer. Brewer’s yeast is also sold as a nutritional supplement due its high levels of selenium, protein, and B-complex vitamins. Unlike other types of baking yeasts, it’s high in chromium, an essential mineral that helps with maintaining our blood sugar levels. Excessive brewer’s yeast in your intestine can occur due to surgery as well. Sometimes after surgery, patients are given antibiotics to control their infection. Unfortunately, as a consequence of these antibiotics, some of the bacteria in the patient’s digestive tract are killed off. The resulting loss allows a growth of brewer’s yeast to take hold in the patient’s gut. See, Cordell and McCarthy, A Case Study of Gut Fermentation Syndrome (Auto-Brewery) with Saccharomyces cerevisiae as the Causative Organism, International Journal of Clinical Medicine, 309, 310 (2013), http://www.scirp.org/journal/PaperInformation.aspx?PaperID=33912#.VPBc5vnF_ZN. Have a few sandwiches and you can get drunk!
It should be noted, however, that gut fermentation syndrome is mainly attributed to Asian and American Indian peoples. It's all about enzymes. When the liver processes ethanol, the enzyme alcohol dehydrogenase first converts it to acetaldehyde. In most people a second enzyme, aldehyde dehydrogenase (ALDH), quickly converts the acetaldehyde to harmless acetate. But roughly 50 percent of Japanese and other East Asians and some American Indians (but practically no Europeans or Africans) have a mutated gene that impairs ALDH activity. Due to the fact they have no ALDH, when they consume alcohol, or their bodies produce natural ethanol, it leaves them with a build up of acetaldehyde in their system. That excess causes numerous unwanted symptoms and can also produce more ethanol, thereby giving them a higher BAC than would normally be.
There is a proposed clinical test for gut fermentation syndrome. A patient is given a fasting glucose challenge of 5 Gm glucose orally. One gram of glucose is given in a hardened gelatin capsule to ensure passage into the duodenum. Blood glucose levels and blood ethanol levels were measured at 1 hour. Fasting blood alcohol levels were zero in nearly all subjects but 61% of the 510 subjects showed an increase in blood alcohol levels on the average of 2.5 mg/dl (range 1.0 - 7.0 mg/dl). This compared to near zero blood alcohol levels in the control group given the same challenge. The phenomenon of gut fermentation was summarized with the above proposed diagnostic method. K. Eaton, “Gut Fermentation: A Reappraisal of an Old Clinical Condition with Diagnostic Tests and Management: Discussion Paper,” Journal of the Royal Society of Medicine, Vol. 84, No. 11, 1991, pp. 669-671.
In the prosecution of OWI/DUI cases, the concentration of ethanol in blood, breath or urine because of drinking alcohol constitutes important evidence for prosecuting drunk drivers. But what if the reliability of the results of forensic alcohol analysis are often challenged by body brewing its own alcohol?. One such argument for acquittal concerns the notion that alcohol could be produced not by drinking alcohol but because the person had eaten food and was suffering from auto-brewery syndrome.