Study of 52 Astronauts Finds Gut Bacteria Shift to Protein Fermentation Within Weeks in Space
Updated
Updated · srpske.rs · Aug 15
Study of 52 Astronauts Finds Gut Bacteria Shift to Protein Fermentation Within Weeks in Space
3 articles · Updated · srpske.rs · Aug 15
Summary
Blood samples from 52 astronauts showed gut bacteria begin fermenting protein more than fiber within weeks of arriving on the International Space Station, with the shift persisting until return to Earth.
Researchers linked the change to slower gut transit in microgravity: food stays longer in the intestine, fiber is depleted, and bacteria switch to protein—though transit time itself was not directly measured.
Nature Communications published the observational study, which used untargeted metabolite analysis across three earlier ISS studies to detect the pattern consistently across different crews and missions.
Protein-fermentation byproducts can enter the bloodstream and are associated in prior research with kidney harm, mood effects and reduced concentration, but this study did not measure those outcomes in astronauts.
For longer missions such as Mars flights, the team said higher-fiber meals, prebiotics and treatments that speed gut motility should be tested in orbit; similar mechanisms may also affect bedridden patients.