Some gut bacteria produce ethanol, an alcohol, in small quantities. This alcohol can contribute to fat buildup in the liver, leading to non-alcoholic fatty liver disease (NAFLD).
See the scientific wording
Gut bacteria that produce small amounts of ethanol drive the development of non-alcoholic fatty liver disease (NAFLD).
Correlational — new studies may shift this
Observational2 moderate-quality studies link this claim to the outcome, but causation is not established.
What the research says
2 studies reviewedSupporting (2)
Case-Control StudyHuman2023
This study found that people with a severe kind of fatty liver disease have more alcohol-making bacteria in their gut, which supports the idea that these bacteria produce small amounts of alcohol that can harm the liver.
Fatty Liver Disease Caused by High-Alcohol-Producing Klebsiella pneumoniae.
Cohort StudyAnimal2019
This study found that a type of gut bacteria that makes alcohol is present in many people with fatty liver, and when given to mice, it gives them fatty liver too, showing that bacteria-made alcohol can cause the disease.
Contradicting (0)
No contradicting studies found yet
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Score breakdown, mechanism chain, raw evidence, ideal studies needed & 2 supporting studies
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