Ferritin (Iron Stores)

Ferritin is your body's iron-storage protein, and the standard first marker used to assess iron reserves — both high and low readings matter.

Reference range

Male: 30–300 ng/mL (optimal 50–200 ng/mL)
Female: 15–200 ng/mL (optimal 30–150 ng/mL)

Watch points

High: at or below 30 ng/mL
Borderline: at or below 40 ng/mL

Watch points — female

High: at or below 15 ng/mL
Borderline: at or below 30 ng/mL

Why hard-training athletes watch it

An endurance-leaning training block and a lean, low-red-meat cut can quietly drop ferritin over months (fatigue and stalled recovery are the usual tip-off), while it can also run high with other training and dietary patterns — direction matters as much as the number itself.

When to retest

Retest alongside a full iron panel — not ferritin alone — if you notice unexplained fatigue or recovery that isn't matching your training load.

Talk to your clinician

Discuss iron stores with your clinician — low ferritin can mean iron deficiency. Low ferritin with fatigue symptoms is worth a clinician visit before supplementing iron on your own — oversupplementing iron carries its own risks.