A recent article published by Medscape and authored by Obede Junior discussed new findings related to auto-brewery syndrome (ABS), a medical condition in which alcohol production takes place in the gut after eating carbohydrate-rich foods. In addition, it examined new findings published in Nature Microbiology, which suggest that alcohol produced by gut microbes may play a role in metabolic liver disease, even in people who do not consume alcohol.
The study included 22 patients diagnosed with ABS. It was found that in a supervised setting without drinking alcohol, participants developed significant blood alcohol levels and showed clear signs of intoxication, while remaining symptom-free during fasting or low-carbohydrate diets. Although described decades ago, ABS has often been dismissed, leaving many patients misdiagnosed and facing personal, professional, and legal consequences.
The results of the research study demonstrated that gut bacteria, rather than fungi, are the primary source of endogenous ethanol production in auto-brewery syndrome, challenging earlier assumptions based on Candida overgrowth. Furthermore, metagenomic and metabolomic analyses showed higher ethanol production in affected individuals, increased abundance of Proteobacteria such as E. coli and K. pneumoniae, and reduced microbial diversity, with bacterial fermentation pathways driving alcohol synthesis. It was also found that antibacterial treatment abolished ethanol production in cultures, whereas antifungal therapy had no effect, confirming the bacterial origin and explaining why prior antifungal-focused treatments were often ineffective. Moreover, bacterial strain-level analysis showed that people with ABS carry specific E. coli strains that tolerate and produce more ethanol than typical commensal strains.
Over the course of the study, one patient with ABS achieved sustained remission after intensive antibiotic therapy followed by repeated fecal microbiota transplantation (FMT), with symptom resolution lasting more than 16 months and metagenomic evidence of replacement of ethanol-producing strains. The findings of the study also suggest that effective treatment may require not only suppression of ethanol-producing bacteria, but also restoration of a stable, protective gut microbiome. “[Our] study high-lights the importance of the gut microbiome and microbial metabolites to human health,” concluded the authors.
