Iron Deficiency and Hair Loss: Why Your Doctor's 'Normal' Blood Work Might Be Wrong

The Ferritin-Hair Loss Connection

One of the most frustrating experiences in dealing with hair loss is being told your blood work is "normal" while your hair continues to thin. This disconnect often comes down to a single number that many doctors overlook: ferritin.

Ferritin is the protein that stores iron in your body. While hemoglobin (the iron-containing protein in red blood cells) is what most people think of when they think of iron status, ferritin is a far more sensitive indicator of iron availability at the cellular level — and hair follicles are extremely sensitive to iron availability.

Why Standard Lab Ranges Are Misleading

Most clinical laboratories flag ferritin as "low" only when it falls below 12–15 ng/mL. However, research specifically examining hair loss has found that hair shedding may not resolve until ferritin reaches at least 70 ng/mL, and some trichologists recommend levels of 80–100 ng/mL for optimal hair growth. This means you could have a ferritin level of 25 ng/mL — which your doctor considers normal — and still be experiencing significant hair loss due to iron insufficiency.

How to Optimize Your Iron Status

If your ferritin is below 70 ng/mL and you're experiencing hair loss, work with your healthcare provider to optimize your iron status. Dietary strategies include increasing consumption of heme iron sources (red meat, poultry, seafood) and pairing non-heme iron sources (legumes, leafy greens, fortified foods) with vitamin C to enhance absorption. Avoid consuming iron-rich foods with coffee, tea, or calcium-rich foods, as these inhibit absorption.

Iron supplementation (specifically ferrous bisglycinate) may be appropriate if dietary optimization is insufficient, but should be guided by blood work and monitored to avoid iron overload. Ferrous bisglycinate is generally better tolerated than ferrous sulfate with fewer gastrointestinal side effects. Our hair loss protocols include evidence-based iron dosing recommendations tailored to your age group.