What is Ferritin?
Ferritin often reflects iron stores, but it can also increase during inflammation or recovery independent of iron levels. That is why ferritin is commonly interpreted together with serum iron, transferrin, and transferrin saturation. The combination and trend provide the clearest picture.
Why is Ferritin relevant?
Ferritin reflects iron stores and also rises with inflammation, making it simultaneously an iron marker and an acute-phase protein. Low values are associated with fatigue, poor athletic performance, and hair loss; high values can indicate iron loading but equally often a smouldering inflammatory process. For athletes, women of reproductive age, and vegetarians, ferritin is a marker you do not want to miss.
How to read Ferritin in context
An isolated ferritin value is rarely enough. Combine with serum iron, transferrin, transferrin saturation, and hs-CRP: low ferritin with low saturation and high transferrin classically signals iron deficiency, while average ferritin with elevated hs-CRP can still mask a hidden deficiency. For athletes the functional optimum often sits above the standard lower limit — a value just within 'normal' can still cause symptoms.