Myths vs facts: Eisen-Ferritin Selbsttest and Sport

Iron and ferritin self-tests are often marketed to athletes for performance optimization or deficiency detection. Fact: Ferritin is a useful marker of iron stores, but a single self-test without medical supervision can be misleading. Athletes do have an increased risk of iron deficiency (e.g., via hemolysis, sweat losses, increased turnover) but also of iron overload (e.g., hemochromatosis). A self-test provides only a snapshot, influenced by inflammation, infection, or time of day. Without parallel measurement of CRP, transferrin saturation, or hemoglobin, interpretation is limited. Myth: 'High ferritin = good iron status' – false, because ferritin is an acute-phase protein and can be elevated during inflammation even with iron deficiency. Fact: Only a physician can make a reliable diagnosis using multiple parameters and clinical history. For athletes, individualized, medically supervised iron assessment is advisable, not a standalone self-test. Evidence: based on physiological knowledge and clinical practice, not on specific self-test studies.