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Hair Loss Blood Tests: Diagnosing Female Hair Loss
Dr. Michael May (FRCS)
Medically reviewed by
Dr. Michael May (FRCS)
Updated on January 26, 2023

Diagnosing women’s hair loss can be difficult. Female hair loss is less common than male hair loss — but it still affects millions of women around the world. Recent research shows that 52% of postmenopausal women have female pattern hair loss [1]. But stress, health conditions, diet, haircare, and other factors can also cause hair loss in younger women.

Unlike with male pattern baldness, diagnosing female hair loss isn’t a simple case of looking at the pattern of hair loss. Hair loss blood tests are often needed to diagnose thinning hair in women.

In this article, you’ll discover:

  • why hair loss blood tests are needed, particularly for women
  • which blood tests are needed and what they tell you about your hair
  • where to get hair loss blood tests.

Why are blood tests needed to diagnose women’s hair loss?

Genetic male hair loss follows a typical pattern: a receding hairline followed by development of a bald spot on the crown. But women’s hair loss rarely follows a pattern. Instead, women tend to experience hair loss across the scalp, which is known as diffuse thinning.

Diffuse thinning is a symptom of multiple hair loss conditions, including:

Because these hair loss types look similar, visual tests aren’t always the best way to diagnose them. The Ludwig Scale, for example, can only measure the extent of hair loss, rather than the type. Blood tests for hair loss are the fastest, most reliable way to determine the cause of hair loss in women.

Blood tests for hair loss

Trichological blood tests measure several factors related to hair loss:

  • Thyroid hormone levels
  • Sex hormone levels
  • Iron and ferritin levels
  • Complete blood count
  • Vitamin D levels
  • Vitamin B levels
  • Blood sugar levels
  • ESR and C-reactive protein levels

Here’s a rundown of each type of blood test and what it can show you about your hair.

Thyroid levels

Hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid) can cause hair loss if left untreated. Your thyroid produces hormones known as TSH, FT3 and FT4. A blood test measures how much of each hormone you’re producing, determining whether you have an overactive or underactive thyroid.

Hormone levels

Sex hormone levels play a big part in maintaining hair growth in women as well as men. Women produce testosterone, which metabolises into DHT. DHT binds to androgen receptors in the hair follicles, causing them to shrink and stop producing hair.

As well as thyroid hormones, a blood test typically measures sex hormone levels, including:

  • Testosterone
  • Oestradiol
  • Androstenedione
  • Prolactin
  • FSH (follicle-stimulating hormone)
  • Luteinizing hormone.

Hormone levels can also indicate the presence of conditions like polycystic ovary syndrome, which has also been linked to hair loss.

Iron and ferritin levels

Hair loss is a less common symptom of anaemia, or iron deficiency. There may also be a link between iron deficiency and hair texture.

Studies have shown that levels of serum ferritin (the blood protein that contains iron) are lower in women with female pattern hair loss than those with healthy hair [2]. Lack of iron may also contribute to the development of alopecia areata [3]. So testing your iron and ferritin levels can give an insight into which type of hair loss you have.

Complete blood count

CBC or full blood count measures individual components of your blood, including red blood cells, white blood cells, and platelets. This can indicate signs of inflammation around the follicles, signalling an autoimmune condition.

Vitamin D levels

Lack of vitamin D has been linked with autoimmunity, so it may worsen or cause autoimmune hair loss conditions like alopecia areata [4]. Research also suggests vitamin D deficiency can play a part in the progression of female pattern hair loss [5].

Learn more about the link between vitamin D and hair loss.

Vitamin B levels

There are several different B vitamins, many of which have been linked with hair loss. These include:

  • Folate (vitamin B9) — also known as folic acid; may contribute to development of alopecia areata [3]
  • Biotin (vitamin B7) — learn about biotin and hair loss
  • Vitamin B12 — may also contribute to alopecia areata development [6]

Hair loss blood tests will check your vitamin B levels to test for deficiency.

Blood sugar

Blood sugar level is an important indicator of diabetes. In particular, type 2 diabetes may be linked with hair loss. One study found that type 2 diabetes was associated with increased risk of severe hair loss on the central scalp in African American women [7].

ESR and C-reactive protein

Erythrocyte sedimentation rate (ESR) and C-reactive proteins (CRP) levels can indicate systemic inflammation. Certain types of scarring alopecia are often associated with inflammation around the hair follicles.

Where should you get hair loss blood tests done?

In some cases your GP will perform the necessary blood tests for you. Hair loss blood tests carried out through your GP are usually free.

But a GP may not read the results in the same way as a trichologist. What’s considered normal for your general health may still be damaging your hair. Take your test results to a professional trichologist for further analysis.

You can also get blood tests done at a private hair clinic. Our trichology team can diagnose your hair loss condition based on your hair loss blood tests, regardless of your age, sex, or gender. We’ll then use this information to create a personalised treatment plan for your hair loss.

Will I need a hair transplant for my hair loss?

A female hair transplant may be a possibility following your diagnosis. But there are lots of other non-invasive treatments to try first. Minoxidil and other hair transplant alternatives are often worth trying first. The trichology team at the Wimpole Clinic is available to provide all the free, impartial advice you need to help recover your hair.

To get your personalised treatment plan, book a free consultation at the Wimpole Clinic.

Hair Loss Blood Tests: Diagnosing Female Hair Loss, Wimpole Clinic


  1. Prevalence of female pattern hair loss in postmenopausal women: a cross-sectional study
  2. Iron Plays a Certain Role in Patterned Hair Loss
  3. Serum vitamin B12, folate, ferritin, and iron levels in Turkish patients with alopecia areata
  4. Vitamin D and the Immune System
  5. Serum Vitamin D3 Level in Patients with Female Pattern Hair Loss
  6. Serum holotranscobalamine, vitamin B12, folic acid and homocysteine levels in alopecia areata patients
  7. Association of type 2 diabetes with central-scalp hair loss in a large cohort study of African American women
Dr. Michael May (FRCS)
Medically reviewed by Dr. Michael May (FRCS)Updated on January 26, 2023
The Wimpole Clinic offers FUE Hair, Beard & Eyebrow Transplants & Trichology.
Talk to a specialist ☎ 020 7935 1861.
Dr. Michael May (FRCS)
Medically reviewed by
Dr. Michael May (FRCS)
Updated on January 26, 2023

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