Evidence check: Ferritin Eisenmangel in the context of sleep

The link between ferritin (iron deficiency) and sleep is clinically relevant. Low ferritin levels are associated with Restless Legs Syndrome (RLS) and subsequent sleep disruption. Evidence is moderate: observational studies and clinical guidelines support ferritin testing in RLS patients and recommend iron supplementation when levels fall below 50–75 µg/L. However, not all iron deficiency causes sleep issues, and other factors (sleep hygiene, stress, other deficiencies) are important. Self-supplementation without medical supervision is risky because iron overload can be harmful. Consumer DNA tests do not measure ferritin directly; that requires a blood test. Genetic variants (e.g., HFE) can indicate predisposition but not current deficiency. Conclusion: Ferritin and sleep are connected, but the evidence is primarily clinical, not genetic. Medical diagnosis is essential before supplementation.