wie zuverlässig sind heimtests für den darm? — which blood markers matter?

The reliability of home gut tests (e.g., microbiome analyses) is limited. They typically measure bacterial composition and occasionally inflammatory markers like IL1B, but clinical validity is weak. No randomized controlled trials demonstrate that these tests lead to improved health outcomes. Evidence is based on observational studies (associative links) and mechanistic data. Such tests can indicate gut diversity but are not diagnostic and do not replace medical evaluation. Which blood markers matter: For gut health, relevant blood markers include CRP (systemic inflammation), fecal calprotectin (though not a blood test), and possibly zonulin (gut permeability), but these are not mentioned in the provided context. The available information does not specify blood markers for the gut. Therefore, the evidence level is 'mixed': there are mechanistic and observational hints, but no robust clinical confirmation. Safety note: Do not rely solely on home tests; consult a doctor for persistent symptoms.