Evidence check: Eisen-Ferritin Selbsttest in the context of Sport

An iron/ferritin self-test can be relevant for athletes, as iron deficiency is common (especially in endurance sports) and can impair performance. However, the reliability of such home tests is limited: ferritin is an acute-phase reactant, meaning inflammation, infection, or liver issues can skew results, so a low value does not always indicate true deficiency. Moreover, standardized reference ranges for athletes are often lacking. A physician-supervised lab test (including CRP, transferrin saturation) is more reliable. Evidence for self-testing in sports is moderate – it may serve as a screening tool but not as a standalone diagnosis. Caveat: overinterpretation can lead to unnecessary supplementation or overlooking other causes.