Symptom → lab tests
What blood tests should you get for hair loss?
Short answer
Diffuse hair shedding is often driven by something measurable: low iron stores (ferritin), thyroid dysfunction (TSH), hormone shifts (testosterone, DHEA-S, SHBG) and low vitamin D or zinc. A first workup is ferritin, TSH, vitamin D and a hormone check appropriate to your sex; results guide whether the cause is nutritional, thyroid or androgen-related.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
When should you see a clinician instead of ordering a test?
- Sudden patchy hair loss, scalp pain, redness or scarring — see a dermatologist
- Hair loss with other new symptoms such as weight change, fatigue and joint pain together
Why these tests for hair loss?
Hair follicles are sensitive to iron, thyroid hormone and androgens. Ferritin is the single most common finding in women with diffuse shedding — dermatologists often look for a level well above the lab's lower limit. Thyroid disease in either direction causes shedding, and androgen excess (in women) or sensitivity (in men) drives pattern thinning.
Vitamin D and zinc are supporting checks; both are frequently low and easy to correct. Autoimmune and scalp causes can't be found by blood work and need a clinician or dermatologist.
Which conditions do these tests help evaluate?
- Hair Loss — Thyroid, iron/ferritin, hormones and vitamins behind unexplained shedding.
- Thyroid Problems — TSH, Free T4/T3 and antibodies to evaluate an under- or over-active thyroid.
- PCOS — Androgens, LH/FSH, insulin and thyroid markers to investigate PCOS.
Which tests, and what do they cost?
Prices are cash-pay; every order adds one $6 lab processing fee. Physician authorization is included; no insurance or referral needed.
| Test or panel | Type | Price | Fasting | Results |
|---|---|---|---|---|
| Women's Hair Health PanelSaves $401.82 vs ordering the tests separately | Panel · 19 tests | $469.99 | No | 4–7 business days |
| Men's Hair Health PanelSaves $391.82 vs ordering the tests separately | Panel · 19 tests | $499.99 | No | 4–7 business days |
| Ferritin | Test | $24.99 | No | 1–3 business days |
| TSH (Thyroid Stimulating Hormone) | Test | $26.99 | No | 1–3 business days |
| Vitamin D, 25-Hydroxy | Test | $41.99 | No | 1–3 business days |
| Testosterone, Free & Total | Test · 2 biomarkers | $54.99 | No | 3–5 business days |
| DHEA-Sulfate | Test | $32.99 | No | 1–3 business days |
| Zinc | Test | $26.99 | Yes | 3–6 business days |
| CBC with Differential | Test · 14 biomarkers | $21.99 | No | 1–3 business days |
Common questions
What ferritin level matters for hair?
Reference ranges start around 11–30 ng/mL, but many dermatologists prefer stores comfortably above that before ruling iron out. Your clinician interprets the number with your CBC and symptoms; don't supplement iron without a confirmed low level.
Can hair loss be from a thyroid that's only slightly off?
Yes — both hypo- and hyperthyroidism cause shedding, and treating the thyroid usually stops it over several months. TSH is the first check.
Educational content, not a diagnosis. Lab results are one input; a clinician interprets them with your history and exam.