How are Ferritin Eisenmangel and Sport related?

The relationship between ferritin, iron deficiency, and sport is bidirectional. Ferritin reflects body iron stores; low levels indicate iron deficiency, which is common among athletes, especially in endurance sports due to increased iron losses (sweat, urine, GI bleeding) and higher demand for erythropoiesis and muscle repair. Intense exercise also upregulates hepcidin, reducing dietary iron absorption. Iron deficiency can impair athletic performance by limiting oxygen transport and mitochondrial function. However, genetic variants (e.g., HFE) have only a small effect on iron status; lifestyle factors like diet and training load are more influential. MyBody-X tests may include HFE variants, but their predictive value for sport-related iron deficiency is limited. Ferritin <30 ng/mL indicates absolute deficiency; 30–100 ng/mL may be functional deficiency. Athletes should monitor ferritin regularly, but not rely solely on genetic tests. Evidence for direct genetic links between ferritin and sport is moderate, mostly observational. Caveat: ferritin is an acute-phase reactant; inflammation can falsely elevate levels.