Ferritin Eisenmangel: what are common causes?

Low ferritin indicates depleted iron stores. Common causes include: (1) Blood loss – heavy menstruation, gastrointestinal bleeding (ulcers, hemorrhoids, colon cancer), or frequent blood donation. (2) Inadequate dietary intake – especially in restrictive diets (vegan/vegetarian) without iron-rich foods or supplementation. (3) Malabsorption – celiac disease, atrophic gastritis, Helicobacter pylori infection, or after bariatric surgery. (4) Increased demand – pregnancy, growth spurts in children/adolescents, endurance training. (5) Chronic diseases – inflammation, heart failure, or cancer can cause functional iron deficiency (ferritin may be normal due to acute-phase reaction). Caveat: Ferritin is an acute-phase reactant; in infection or inflammation, levels may be falsely normal or elevated despite low iron stores. A ferritin <30 µg/L is generally considered deficient. Always interpret with clinical context and additional labs (e.g., transferrin saturation, CRP). MyBody-X tests do not measure ferritin; this requires clinical lab testing.