Iron Status Assessment and Management for Optimal Hair Growth

Reference Ranges for Iron‑Related Laboratory Tests

Serum iron in healthy adults is typically 50–175 µg/dL. 1
Total iron‑binding capacity (TIBC) normally ranges from 250–370 µg/dL (45–66 µmol/L). 1
Transferrin saturation (TSAT) is considered normal between 20 % and 50 %. 1
Serum ferritin reference values:
- Men — 20–250 µg/L (assay‑dependent range 24–336 µg/L)
- Women — 20–200 µg/L
Hemoglobin reference ranges:
- Men — 13.5–17.5 g/dL
- Women — 12.0–15.5 g/dL
Mean corpuscular volume (MCV) normal range is 80–100 fL, decreasing in iron‑deficiency anemia. 1
Serum transferrin concentration is 200–400 mg/dL, rising proportionally when iron demand increases. 1

Ferritin behaves as an acute‑phase reactant; inflammation, infection, or illness can falsely elevate its level. 1
In the presence of inflammation, ferritin values up to 100 µg/L may still be compatible with true iron deficiency. 3
When inflammation is absent, ferritin < 30 µg/L definitively indicates iron deficiency. 3
Serum iron exhibits greater day‑to‑day variability than hemoglobin and is influenced by recent meals and diurnal rhythms, limiting its standalone diagnostic utility. 1

Ferritin combined with transferrin saturation provides the most reliable assessment of iron status. Low ferritin (<30 µg/L) together with low TSAT (<16 %) unequivocally confirms absolute iron deficiency. 3
Normal serum iron and TIBC values do not exclude iron deficiency; they must be interpreted alongside ferritin and TSAT. 3

After correcting iron deficiency, aim for a serum ferritin level ≥ 100 ng/mL to ensure sufficient iron stores for optimal hair growth. 3
Maintain transferrin saturation ≥ 20 % to confirm adequate iron availability to the hair follicles. 3

Gastrointestinal intolerance to oral iron preparations. 3
Chronic kidney disease with estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73 m². 3
Lack of hematologic response after 4–8 weeks of adequate oral iron therapy. 3