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Ferritin & Iron Thresholds in Hair Loss: What the Science Shows
Iron deficiency without anemia is one of the most underdiagnosed triggers for chronic hair shedding. Serum ferritin acts as the primary biomarker for cellular iron stores in hair matrix cells.
The 50 ng/mL Hair Threshold
While standard laboratory reference ranges define normal ferritin as low as 15 ng/mL, dermatological consensus indicates that hair follicle matrix cells require serum ferritin levels of 50–70 ng/mL to maintain optimal anagen growth.
Mechanism of Iron Depletion in Follicles
Ribonucleotide reductase, an essential iron-dependent enzyme, limits DNA synthesis in rapidly dividing follicle matrix cells. When ferritin drops below 50 ng/mL, matrix cell division slows, causing premature catagen transition.
Frequently asked questions
What ferritin level is needed for hair growth?
Dermatologists generally target serum ferritin levels of at least 50 ng/mL (and ideally 70 ng/mL) for active hair regrowth.
Related reading: full research article →
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Informational only, not medical advice. Always consult a qualified clinician before starting or changing treatment.