What role does ADH1B play in gut health?

ADH1B encodes alcohol dehydrogenase, which metabolizes ethanol in the liver and gastrointestinal tract. A fast-metabolizing variant (rs1229984) reduces alcohol tolerance and may lower alcohol intake. Regarding gut health directly—such as microbiome composition or intestinal barrier function—there is no strong human evidence. An indirect link exists via alcohol consumption: alcohol can disrupt the gut barrier and promote dysbiosis. ADH1B variants influence drinking behavior, thus indirectly affecting alcohol-related gut damage. However, the evidence is mechanistic and not sufficient for clinical guidance. Caveat: consumer DNA tests for ADH1B are not a diagnostic tool for gut disorders.