Laboratory normal against the hair-relevant range
Four markers, each drawn twice on one scale: the laboratory reference range the guides report, and the narrower range the hair literature points to. The shaded stretch of each reference bar is where a result can be reported as normal and still sit outside the hair range. Each row is quoted from a single guide, named on the row; where our guides disagree the ranges are printed, not merged.
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Every number printed on this figure, and where it came from
Each quantity the diagram prints, the sentence it was taken from, and the guide that sentence is in. The build refuses to publish if one of these sentences is no longer in the guide it names.
| Value | What it is, and the sentence behind it | Source guide |
|---|---|---|
| 15-150 ng/mL | Laboratory reference range for ferritin in women, the wide bar on the ferritin row “| Ferritin | 15-150 ng/mL (women) | >70 ng/mL |” | Hair Loss Blood Tests: What to Request and Why (2026) |
| 70 and above ng/mL | The ferritin level the guide gives as optimal for hair, drawn open-ended to the right “| Ferritin | 15-150 ng/mL (women) | >70 ng/mL |” | Hair Loss Blood Tests: What to Request and Why (2026) |
| 50 ng/mL | Ferritin level below which hair loss is reported as associated “Hair loss associated with <50 ng/mL” | Hair Loss Blood Tests: What to Request and Why (2026) |
| 16.3 ng/mL | Mean ferritin reported in hair loss patients “Hair loss patients: average ferritin 16.3 ng/mL” | Hair Loss Blood Tests: What to Request and Why (2026) |
| 60.3 ng/mL | Mean ferritin reported in controls without hair loss “Controls without hair loss: average ferritin 60.3 ng/mL” | Hair Loss Blood Tests: What to Request and Why (2026) |
| 70-100 ng/mL | The ferritin band the ferritin guide calls optimal for hair, cited in the row note “Optimal for hair (70-100 ng/mL)” | Ferritin and Hair Loss: Optimal Levels for Hair Growth (2026) |
| 30-100 ng/mL | Laboratory reference range for 25-hydroxyvitamin D, the wide bar on the vitamin D row “| Vitamin D | 30-100 ng/mL | 50-80 ng/mL |” | Hair Loss Blood Tests: What to Request and Why (2026) |
| 50-80 ng/mL | The vitamin D range the guide gives as optimal for hair “| Vitamin D | 30-100 ng/mL | 50-80 ng/mL |” | Hair Loss Blood Tests: What to Request and Why (2026) |
| 30 ng/mL | The level many laboratories report as sufficient, quoted in the row note “Many labs report >30 as "sufficient"” | Hair Loss Blood Tests: What to Request and Why (2026) |
| 0.4-4.0 mIU/L | Laboratory reference range for TSH, the wide bar on the TSH row “| TSH | 0.4-4.0 mIU/L | 1.0-2.5 mIU/L |” | Hair Loss Blood Tests: What to Request and Why (2026) |
| 1.0-2.5 mIU/L | The TSH range the guide gives as optimal for hair “| TSH | 0.4-4.0 mIU/L | 1.0-2.5 mIU/L |” | Hair Loss Blood Tests: What to Request and Why (2026) |
| 70-120 µg/dL | Laboratory reference range for serum zinc, the wide bar on the zinc row “**Normal lab range**: 70-120 µg/dL” | Women's Hair Loss Blood Tests to Request |
| 80-100 µg/dL | The serum zinc range the guide gives as optimal for hair “**Optimal for hair**: 80-100 µg/dL” | Women's Hair Loss Blood Tests to Request |
| 84.3 µg/dL | Mean serum zinc reported in hair loss patients “Hair loss patients had significantly lower zinc (84.3 µg/dL) vs controls (97.9 µg/dL)” | Women's Hair Loss Blood Tests to Request |
| 97.9 µg/dL | Mean serum zinc reported in controls “Hair loss patients had significantly lower zinc (84.3 µg/dL) vs controls (97.9 µg/dL)” | Women's Hair Loss Blood Tests to Request |
| 0.5-2.5 mIU/L | The TSH range the thyroid guide gives, which differs from the one drawn “Optimal for symptoms: 0.5-2.5 mIU/L” | Thyroid Hair Loss: Complete Testing Guide + Optimal Levels (2026) |
| 30-50 ng/mL | The vitamin D range the vitamin D guide gives, which differs from the one drawn “Optimal vitamin D level for hair health is 30-50 ng/mL” | Vitamin D Hair Loss: Optimal Levels + Recovery Timeline (2026) |
| 60-120 µg/dL | The serum zinc reference range the blood test guide gives, which differs from the one drawn “| Zinc | 60-120 mcg/dL | Mid-upper range | Lower range associated with shedding |” | Hair Loss Blood Tests: What to Request and Why (2026) |
Where this figure appears
Hair Loss Blood Tests: What to Request and Why (2026) · Ferritin and Hair Loss: Optimal Levels for Hair Growth (2026)