Evidence check: Ferritin Eisenmangel in the context of allergy

The question of ferritin (iron stores) in the context of allergy is complex. Ferritin is a biomarker for iron status. Iron deficiency can affect immune function, as iron is crucial for immune cell activity (e.g., T‑cells). Some studies suggest low ferritin may be associated with increased risk of atopic conditions like eczema or hay fever, but evidence is inconsistent. Other studies found no clear link or even opposite effects. Additionally, chronic inflammation (e.g., in allergies) can alter ferritin levels because ferritin is also an acute‑phase protein. DNA tests for iron metabolism genes (e.g., HFE, TMPRSS6) provide only weak, mechanistic clues and are not suitable for predicting iron deficiency or allergy risk. Clinical ferritin measurement (fasting, with CRP to correct for inflammation) remains the gold standard. Iron supplementation without proven deficiency is not recommended and might even exacerbate inflammatory responses in some allergic individuals. Conclusion: ferritin and allergy have a loose association, but the evidence is mixed and insufficient for personalized recommendations from DNA tests.