Which Blood Tests Are Required for Hair Loss in Women?

Hair loss in women can be a distressing experience, often affecting one’s confidence and emotional well-being. While hair loss is commonly associated with men, many women experience it as well, with causes ranging from genetic factors to hormonal imbalances and nutritional deficiencies. Blood tests play a crucial role in diagnosing the underlying causes of hair loss in women, enabling medical professionals to tailor effective treatment plans.

In this article, we will outline the key blood tests that are typically required to identify the root cause of female hair loss, offering insights into how these tests help make treatment decisions.

Common Causes of Hair Loss in Women

Before discussing specific blood tests, it is important to understand some of the most common causes of hair loss in women. The three main types of hair loss that are frequently diagnosed include:

Androgenetic Alopecia: Also known as female pattern hair loss, this is the most common type of hair loss in women and is often related to genetics and hormonal imbalances. It typically presents as thinning hair at the top of the head, or widening of hair partings¹. This is often seen in those suffering from PCOS and women who have gone through menopause.
Telogen Effluvium: This condition occurs when a large number of hair follicles enter the resting (telogen) phase of the hair growth cycle, causing hair to shed excessively. Telogen effluvium is often triggered by stress, major surgery, childbirth, or significant illness².
Alopecia Areata: An autoimmune condition where the immune system mistakenly attacks hair follicles, leading to patchy hair loss. In more severe cases, it can cause complete baldness³.

Identifying the underlying cause of hair loss is essential for effective treatment, and blood tests are an important diagnostic tool in this process.

Blood Tests for Diagnosing Hair Loss in Women

When a woman experiences hair loss, a physician or dermatologist will often recommend several blood tests to identify any underlying medical conditions or deficiencies contributing to the problem. These tests help rule out or confirm various potential causes, such as hormonal imbalances, nutritional deficiencies, or autoimmune diseases.

1. Full Blood Count (FBC)

A Full Blood Count (FBC) is a routine blood test that measures the levels of different components in the blood, including red blood cells, white blood cells, haemoglobin, and platelets. This blood test can help detect several conditions that may lead to hair loss, including anaemia, which occurs when there is a deficiency in red blood cells or haemoglobin. Anaemia is a common cause of hair thinning, particularly in women with heavy menstrual cycles or low iron intake⁴. Treating any underlying anaemia can help with hair growth and overall health.

2. Ferritin and Iron Studies

Ferritin is a protein that stores iron in the body, and low ferritin levels can indicate an iron deficiency, even before anaemia develops. Low iron levels can impair the production of healthy hair, leading to loss. Ferritin and iron studies, which measure the levels of iron in the blood, are often among the first tests ordered for women experiencing hair loss. Research has shown that low ferritin levels are associated with hair shedding and may contribute to female pattern hair loss and telogen effluvium^5,6.

3. Thyroid Function Tests (TFTs)

The thyroid gland, located in the neck, plays a significant role in regulating hair growth. Both hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid) can lead to hair loss. Thyroid function tests (TFTs) measure levels of your body’s thyroid hormones to assess whether the thyroid gland is functioning properly. In cases where thyroid dysfunction is detected, medical treatment to balance thyroid hormone levels can often help restore hair growth.

4. Hormonal Panel (Androgens, Oestrogen, and Others)

Hormonal imbalances are a common cause of hair loss in women. An imbalance in hormones such as testosterone, dihydrotestosterone (DHT), oestrogen, and progesterone can disrupt the hair growth cycle, causing thinning hair or pattern hair loss⁷. In conditions such as polycystic ovary syndrome (PCOS), elevated androgen (male hormone) levels in the body can cause hair loss, as well as other fertility issues.

A hormonal panel typically includes tests for:

Testosterone: High levels of testosterone can be converted into another form, dihydrotestosterone (DHT), which shrinks hair follicles and leads to hair thinning.
DHEA-Sulfate: Elevated levels of this hormone can also contribute to hair loss and is often associated with conditions like PCOS.
Oestrogen and Progesterone: Imbalances in these female hormones, particularly during menopause, can trigger hair loss.

Addressing hormonal imbalances through medication or lifestyle changes may help to slow or even reverse hair loss.

5. Vitamin D Levels

Vitamin D is vital for overall health, and plays a crucial role in the hair growth cycle. Studies have shown that women with low levels of vitamin D are more likely to experience hair thinning or diffuse hair loss⁸. Testing for vitamin D levels is a common part of the diagnostic process for women experiencing hair loss, especially for those who live in areas with limited sun exposure, such as the United Kingdom. Increasing vitamin D levels through supplements or healthy sun exposure may improve hair density.

6. Zinc and Other Nutritional Deficiencies

Deficiencies in essential nutrients like B12, zinc, biotin, and folate can also contribute to hair loss. Zinc, in particular, is involved in hair follicle health, and low levels can lead to hair shedding⁹. A blood test to assess zinc levels, along with other nutrients, can help identify whether nutritional supplementation might be beneficial.

7. Autoimmune Screening

An autoimmune condition is where the body attacks its own healthy organs and cells by mistaking them for foreign bodies. For women suspected of having autoimmune conditions, like alopecia areata, autoimmune screening tests may be ordered.These tests typically include antinuclear antibodies (ANA) and other markers that can indicate the presence of autoimmune activity. Early diagnosis and treatment of autoimmune diseases can help reduce these types of hair loss¹⁰.

How These Blood Tests Help Guide Treatment

Blood tests not only help diagnose the root causes of hair loss but also provide a roadmap for treatment. For example:

If low ferritin levels are found, iron supplementation may be recommended to restore iron stores and promote hair regrowth.
In cases of thyroid dysfunction, medications to correct hormone levels can help improve hair density and texture.
Hormonal imbalances, particularly elevated androgens, can be treated with medications like anti-androgens (e.g., spironolactone) to reduce hair thinning.
Nutritional deficiencies can often be corrected with targeted supplementation, helping to reverse hair loss and support new growth.

Conclusion

Hair loss in women can be caused by a variety of factors, from hormonal imbalances to nutritional deficiencies and autoimmune conditions. Blood tests are an essential tool in diagnosing the underlying cause of hair loss, allowing healthcare providers to develop targeted, effective treatment plans. By addressing the root cause—whether it’s low iron levels, thyroid dysfunction, or a hormonal imbalance—many women can restore their hair’s health and vitality.

For women experiencing hair loss, consulting with a healthcare provider or dermatologist and undergoing the necessary blood tests is the first step toward identifying the cause and finding the appropriate treatment. For more tailored treatment plans on how to manage hair loss, our friendly team at The Treatment Rooms are more than happy to help guide you through your hair care journey.

References

NHS. Hair loss in women. Available from: https://www.nhs.uk/conditions/hair-loss/
Harrison S, Sinclair R. Telogen effluvium. Clin Exp Dermatol. 2002;27(5):389-395.
National Alopecia Areata Foundation. Understanding alopecia areata. Available from: https://www.naaf.org
NHS. Anaemia – Symptoms and causes. Available from: https://www.nhs.uk/conditions/anaemia/
Rushton DH, Norris MJ, Dover R, et al. Causes of hair loss and the developments in hair rejuvenation. Int J Cosmet Sci. 2002;24(1):17-23.
Kantor J, Kessler LJ, Brooks DG, Cotsarelis G. Decreased serum ferritin is associated with hair loss in women. J Invest Dermatol. 2003;121(5):985-988.
National Institute for Health and Care Excellence. Polycystic ovary syndrome (PCOS): Diagnosis and management. NICE Clinical Guidelines. 2018.
Ramos PM, Miot HA. Alopecia and vitamin D. J Am Acad Dermatol. 2017;80(4):1169-1170.
Kil MS, Kim CW, Kim SS. Analysis of serum zinc and copper concentrations in hair loss. Ann Dermatol. 2013;25(4):405-409.
McElwee KJ, Shapiro J. Promising therapies for treating and/or preventing alopecia areata. Expert Opin Investig Drugs. 2010;19(7):915-927.