Iron deficiency causes diffuse hair loss in up to 10% of premenopausal women, making it one of the most common and treatable causes of hair thinning. Tracking ferritin levels alongside hair density measurements creates a clear record of whether iron supplementation is translating into actual hair recovery.
Why Iron Deficiency Causes Hair Loss
Hair follicles are among the most rapidly dividing cells in the body and require iron for several critical functions. Iron is essential for DNA synthesis in follicle matrix cells, oxygen delivery to the hair bulb via red blood cells, and enzyme activity in the hair growth cycle.
When ferritin (the body's iron storage protein) drops below 30 ng/mL, the body diverts iron to essential organs and away from hair follicles. This triggers telogen effluvium, where follicles prematurely enter the resting phase and shed 2 to 4 months later.
| Ferritin Level | Hair Impact | Action |
|---|---|---|
| Below 15 ng/mL | Active shedding likely | Immediate supplementation, investigate cause |
| 15 to 30 ng/mL | Shedding possible, suboptimal growth | Begin supplementation, start density tracking |
| 30 to 40 ng/mL | Borderline, some individuals still affected | Continue supplementation, monitor density |
| 40 to 70 ng/mL | Adequate for most, recovery begins | Maintain levels, track density improvement |
| Above 70 ng/mL | Optimal for hair growth | Monitor maintenance, expect continued recovery |
How to Track Iron and Hair Density Together
Baseline both measurements. Get a blood test for ferritin, serum iron, TIBC, and hemoglobin. On the same week, take your first myhairline.ai density scan. This gives you paired starting points.
Log every blood result. After each blood draw, record your ferritin level in the notes section of your next density scan. Include the date, ferritin value, and any supplement changes.
Scan monthly. Monthly density scans capture the gradual recovery pattern. Iron-related hair loss recovery is slow, so monthly intervals provide enough resolution without creating false alarm from normal daily shedding variation.
Track for at least 6 months. The typical timeline from iron normalization to visible density improvement is 3 to 6 months. Full recovery may take 12 months. Short tracking periods miss the delayed recovery pattern.
Common Iron Supplementation Protocols
Your doctor will recommend a specific protocol based on your deficiency severity. Common approaches include:
Ferrous sulfate (325mg tablet, containing 65mg elemental iron): Taken 1 to 3 times daily. Most common first-line treatment. Can cause GI side effects.
Ferrous bisglycinate (25 to 50mg elemental iron): Better tolerated with fewer GI side effects. Slightly lower iron content per dose but better absorption.
Iron infusion: For severe deficiency (ferritin below 15 ng/mL) or poor oral absorption. Raises ferritin levels quickly, typically within 1 to 2 weeks.
Pair supplementation with vitamin C (aids absorption) and avoid taking iron with calcium, coffee, or tea (reduce absorption).
The Recovery Timeline
Understanding the typical recovery timeline helps you interpret your tracking data correctly.
Months 1 to 2 after supplementation begins: Ferritin levels start rising. Shedding may continue or even temporarily increase. Density scans may show continued decline. This is normal.
Months 3 to 4: Ferritin approaches adequate levels (above 40 ng/mL). Shedding slows noticeably. Density scans may show stabilization.
Months 4 to 6: New hair enters the anagen (growth) phase. Density scans begin showing improvement. Short regrowth may be visible.
Months 6 to 12: Progressive density recovery. myhairline.ai scans should show measurable improvement from baseline if iron was the primary cause of hair loss.
If density does not improve after ferritin has been above 40 ng/mL for 6 months, other factors may be contributing. Discuss with your doctor whether androgenetic alopecia, thyroid dysfunction, or other conditions should be investigated. See our female hair loss tracking guide for multi-factor assessment.
Who Should Track Iron and Density Together
Iron-related hair loss tracking is particularly relevant for:
- Premenopausal women with heavy menstrual periods
- Vegetarians and vegans with limited dietary iron intake
- Patients with GI conditions affecting iron absorption (celiac, IBD)
- Post-surgical patients with blood loss
- Pregnant or postpartum women
Start Tracking Today
Get your ferritin tested and take your baseline density scan at myhairline.ai/analyze in the same week. Log your iron values alongside monthly density scans to create the correlation record that shows whether supplementation is working. For more on tracking telogen effluvium recovery from any cause, see our dedicated guide.
This article is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare provider for diagnosis and treatment of iron deficiency and hair loss.