Myths vs facts: Ferritin Eisenmangel and fatigue

Myths vs. facts: Ferritin, iron deficiency, and fatigue. A common myth is that fatigue automatically means iron deficiency. In reality, fatigue has many causes (sleep deprivation, stress, thyroid disorders, vitamin D deficiency). Ferritin is a storage protein; low levels (<30 µg/L) indicate depleted iron stores, but only low hemoglobin confirms anemia. Another myth: high ferritin is always good. Wrong – elevated ferritin can signal inflammation, liver disease, or hemochromatosis. Clinical practice shows: a ferritin test alone is insufficient; a complete blood count, transferrin saturation, and CRP are needed. DNA tests for iron metabolism (e.g., HFE gene) are only useful when hemochromatosis is suspected, not for general fatigue. Supplementation without diagnosis can be dangerous (iron overload). Bottom line: ferritin is a useful marker, but fatigue requires comprehensive evaluation. Evidence: clinical guidelines.