welche blutwerte bei müdigkeit testen — can a microbiome test help?

For unexplained fatigue, standard blood tests include iron/ferritin, vitamin B12, folate, vitamin D, thyroid function (TSH, fT3, fT4), and inflammatory markers (CRP). A microbiome test may provide additional clues about dysbiosis linked to fatigue via the gut-brain axis, but the evidence is mostly mechanistic and not diagnostic. The genetic variants mentioned in your context (e.g., MTHFR, SLC6A4/rs25531) have small effects and do not justify standalone interventions. Microbiome testing should not replace a medical workup; it can be an exploratory tool but lacks strong evidence for guiding fatigue treatment. Always check standard blood values first and discuss results with a physician before taking supplements or making dietary changes.