Hair loss can happen for many reasons. Genetics are common, but nutritional deficiencies, thyroid disorders, hormone changes, and another medical condition may also disrupt the hair growth cycle.
Blood tests for hair loss can help identify hidden problems that may be contributing to hair loss. They cannot diagnose every type of hair loss, but they are useful when shedding is sudden, widespread, or accompanied by fatigue, weight changes, irregular periods, or other symptoms.
At PURE Medical Spa, the PURE Hair ReGrow program begins with a diagnosis-first approach. A PURE Med Spa hair consultation may include a review of your symptoms, medical history, diet, medications, and previous laboratory results.
What Blood Tests Detect Hair Loss?
Patients often ask, what blood tests detect hair loss?
Common tests may include:
- Complete blood count
- Ferritin
- Iron studies
- Thyroid-stimulating hormone
- Free T4
- Vitamin D
- Vitamin B12
- Folate
- Zinc
- Hormone testing when appropriate
Testing depends on your symptoms. Not every patient needs every test.
A proper hair loss diagnosis should also include a scalp examination and PURE Med Spa hair analysis. Bloodwork identifies internal causes, while scalp imaging helps evaluate density, inflammation, miniaturization, and the condition of the follicles.
Iron Deficiency and Hair Loss
Iron deficiency and hair loss are often discussed together, especially in patients with diffuse shedding.
Iron supports red blood cells and oxygen delivery. Low iron stores may affect the follicles and cause more hair to enter the resting phase.
Iron deficiency hair loss may be more common in people with:
- Heavy menstrual periods
- Pregnancy-related changes
- Restrictive diets
- Digestive problems
- Recent blood loss
- Rapid weight loss
Ferritin is commonly tested because it reflects stored iron. However, iron supplements should not be taken without medical guidance. Too much iron may be harmful.
Vitamin Deficiency Hair Loss
Vitamin deficiency hair loss may occur when the body does not receive enough nutrients to support normal follicle activity.
Common vitamin deficiencies linked to hair loss may include:
- Vitamin D deficiency
- Vitamin B12 deficiency
- Folate deficiency
- Zinc deficiency
- Low protein intake
Correcting a true deficiency may help promote hair growth and improve hair quality. However, taking high-dose supplements when no deficiency exists may not improve hair or stop shedding.
Thyroid Hair Loss
Both underactive and overactive thyroid function may cause thyroid hair loss.
The thyroid helps regulate metabolism and the hair growth cycle. People with thyroid disorders may notice diffuse shedding, dry hair, fatigue, temperature sensitivity, or weight changes.
Common tests include TSH and free T4. Treating the underlying thyroid condition may reduce hair loss due to hormonal disruption, although regrowth can take time.
Hormone Testing for Hair Loss
Hormone testing for hair loss may be recommended when thinning is accompanied by:
- Irregular periods
- Acne
- Facial hair growth
- Fertility problems
- Sudden pattern changes
- Signs of polycystic ovary syndrome
Common hormone tests for hair thinning may include testosterone, DHEA-S, prolactin, estradiol, LH, and FSH.
Hormone testing is not required for all men and women. It is usually selected when symptoms suggest an endocrine imbalance.
Blood Tests for Female Hair Loss
Blood tests for female hair loss can help identify causes that may occur alongside female pattern hair loss.
Common causes of female hair loss and hair loss in women include:
- Iron deficiency
- Thyroid disease
- Hormonal changes
- Pregnancy
- Menopause
- Autoimmune conditions
- Nutritional deficiencies
- Genetic thinning
A woman may have more than one issue at the same time. For example, female pattern hair loss may occur together with low iron or vitamin D deficiency.
What If Blood Test Results Are Normal?
Normal laboratory results do not mean your hair concerns are not real.
Many cases of male pattern baldness, female pattern thinning, traction alopecia, or another genetic form of hair loss including a receding hairline can occur with normal bloodwork.
A visible bald spot, widening part, or progressive thinning may require a scalp examination and hair restoration evaluation.
How Doctors Diagnose Hair Loss
Understanding how doctors diagnose hair loss requires looking at the complete picture.
An evaluation may include:
- Medical and family history
- Review of medications
- Scalp imaging
- Hair-pull testing
- Blood tests
- Biopsy when needed
These steps help separate temporary shedding from genetic, hormonal, autoimmune, nutritional, or inflammatory hair thinning causes.
Research Sources
- American Academy of Dermatology: Hair Loss Diagnosis and Treatment
Explains how dermatologists diagnose hair loss using a medical history, scalp examination, blood tests, and sometimes a scalp biopsy. - American Academy of Dermatology: Female Pattern Hair Loss
Reviews the signs and progression of female pattern hair loss, including widening of the part and overall thinning. - American Academy of Dermatology: Alopecia Areata Diagnosis
Notes that blood testing may be used to check thyroid function and healthy levels of iron and vitamins. - NIH Office of Dietary Supplements: Iron Fact Sheet
Provides medical information about iron requirements, deficiency, supplementation, side effects, and safe intake levels.
PURE Hair ReGrow Evaluation
During a PURE Med Spa hair consultation, patients may receive a detailed review of their shedding pattern, scalp health, previous tests, and treatment history.
Based on the findings, PURE Med Spa hair restoration recommendations may include scalp therapies, regenerative care, nutritional correction, medical guidance, or other medical treatments.
Some therapies used to treat hair loss may have FDA approval, while others may be supportive or used based on the provider’s clinical judgment. The right medical hair loss treatment depends on why the hair falls, not simply on how thinning appears.
Call or text 312.312.7873 to schedule your hair loss consultation and learn more about PURE Hair ReGrow.
Explore the PURE Med Spa Hair Restoration program or learn more about PURE scalp treatments for hair loss.
This article is for educational purposes and does not replace medical advice, diagnosis, or treatment from a licensed healthcare provider.