Can low ferritin cause hair loss?
Yes. Low ferritin is a well-documented contributor to telogen effluvium (diffuse shedding) and worsens androgenetic alopecia. Many dermatologists target ferritin ≥40–70 ng/mL in active hair loss, even when CBC and hemoglobin are normal.
Full answer
Yes. Low ferritin is one of the most consistently identified modifiable contributors to hair shedding. The growing follicle is metabolically active and iron-dependent; functional iron depletion shifts follicles prematurely into the telogen (resting) phase, producing the diffuse shedding pattern known as telogen effluvium. Low ferritin also worsens androgenetic alopecia even though it does not cause the underlying genetic susceptibility. Many dermatologists target ferritin ≥40–70 ng/mL in patients with active hair loss, well above the standard 'low normal' threshold, because the conventional lower bound was set against anemia — not against follicle physiology. Provider review reads ferritin alongside thyroid status, vitamin D, protein intake, recent illness, postpartum status, and medications before recommending repletion.
Educational. Not a substitute for individualized provider review.
- Ferritin — Primary source · oMeds
- Reviewed by Dr. Laura Purdy, MD, MBA · Clinical Director, oMeds · Last reviewed 2026-05-29