wie erkenne ich, ob ein selbsttest wissenschaftlich fundiert ist? — which blood markers matter?

To assess whether a self-test is scientifically sound, look for independent peer-reviewed validation studies, regulatory approval (e.g., CE-IVD, FDA clearance), transparent methodology (which genes or biomarkers are measured, reference ranges), and a clear distinction between evidence and marketing claims. Many consumer tests overstate their predictive power. Regarding blood markers, relevance depends on the health question: for metabolic health, HbA1c, LDL cholesterol, and triglycerides are common; for inflammation, hs-CRP; for iron status, ferritin; for bone health, vitamin D. However, a single self-test cannot diagnose a condition and should not replace professional medical evaluation. Results can be influenced by diet, time of day, and lab variability. Always consult a doctor before acting on test results. The evidence for most direct-to-consumer tests is weak to moderate; true clinical validation is often lacking. Caveat: no consumer test can predict lifespan or replace a comprehensive medical workup.