Blood Test for Hair Loss: Who Should Get Tested, Types and Prevention

Introduction

Dealing with hair loss, or alopecia, is a major concern for anyone experiencing it. Alopecia simply means losing hair, either completely or just partially, it affects both sexes of any age group, and it usually develops slowly over time. While it’s natural to feel uneasy finding hair on your pillow, hairbrush, or in the shower drain, try not to panic because it’s completely normal to shed about 100 hair daily from the roughly 100,000 strands covering your head¹. However, it is crucial to monitor the pattern if you notice abnormal hair fall, that is something more than usual or in a patchy distribution. Early observation is the best way to get a timely diagnosis and start effective treatment. 

There are different types of alopecia, and the most common one is known as androgenetic alopecia. It can affect about 80% of males and 50% females and its incidence increases with age². 

Figuring out the cause is confusing right? This blog will guide through everything about hair loss, the main reasons why it happens (from your genes to high stress), the important tests doctors use to diagnose, the different treatments options available, and simple tips to help stop it before it starts. 

What Causes Hair Loss?

There can be several causes that lead to hair loss. These include: 

• Genetic Factor: Although it’s common for our hair to get thinner as we age, hair loss can be influenced by our genes. One common example of hereditary conditions associated with hair loss is androgenetic alopecia (pattern baldness). It is hair loss that runs in the family and happens because your hair follicles are too sensitive to male hormones called androgens³. Pattern baldness is more common in men than women and can start in men right after puberty¹. 
• Stress: Hair loss can be caused by emotional or physical stress also. You may lose large amounts of hair when distressed, but the loss usually stops on its own after 6 to 8 months. This condition is usually short-term, but it can be long-term or chronic under following conditions: 
  • Any major infections in the body 
  • After childbirth 
  • Intense emotional distress 
  • Diet that does not contain protein 
  • Illness including severe blood loss or any major surgery 
  • Medications such as retinoids, birth control pills, blood pressure drugs and certain antidepressants, and pain relievers like NSAIDs¹.

• Nutritional Deficiencies: Iron, zinc and certain vitamins like B12, biotin, D and C are essential nutrients whose deficiencies can cause hair loss⁴. 
• Hormonal Changes: Significant shifts in hormone levels can trigger temporary or permanent hair loss. 
• Thyroid Disorders: Both an overactive (hyperthyroidism) and underactive (hypothyroidism) thyroid can disrupt the balance needed for hair growth⁵. 
• Childbirth or Menopause: The fluctuation and subsequent drop in oestrogen levels after these events can cause excessive temporary shedding of hai^1,5. 
• Medical Conditions 
  • Autoimmune issues like alopecia areata (patchy baldness) or Lupus. 
  • Infections like syphilis or fungal infections. 
  • Post-radiation or chemotherapy¹.  
• Other Factors
  • Trauma or injury caused by burns. 
  • Overuse of heat or chemicals like excessive shampooing and blow-drying.
  • Nervous habits such as continuous hair pulling or scalp rubbing¹.  

Blood Tests for Diagnosing Hair Loss

A simple blood test can often reveal underlying medical problems, such as nutritional deficiencies or hormonal imbalances, that impact hair growth. 

• Thyroid Function Test: The test checks for Thyroxine (T4) Triiodothyronine (T3) and Thyroid stimulation hormone (TSH). Thyroid hormones are strongly linked to hair loss because they control the growth of body cells, including those in the skin. Thyroid Hormones are essential for growth and maintenance of hair follicle; hair loss can signal underlying thyroid dysfunction. Hair loss affects roughly 50% of people with hyperthyroidism and 33% of those with hypothyroidism. Thus, one of the most important tests that is linked to hair loss is Thyroid function test^6,7. 
• Sex Hormone Test:  As mentioned above hair follicle are sensitive to male sex hormones or androgens. Dehydroepiandrosterone sulphate (DHEAS) and Testosterone are types of androgens found in both male and female, high level of these 2 hormones can lead to hair loss. Thus, DHEAS and Testosterone testing is important^8,9. 
• Complete Blood Count: CBC test checks for different components like red blood cells, white blood cells, platelets, haemoglobin, haematocrit and MCV (Mean corpuscular volume). Here CBC is performed to rule out anaemia or infection. Unusual levels of red blood cells, haemoglobin, or haematocrit can signal conditions like anaemia or insufficient iron.  High level of WBC (white blood cell) could be a sign of infection^6,10. 
• CRP (C-reactive Protein): High C-reactive protein (CRP) levels suggest inflammation, which can be a sign of autoimmune disease. An example for autoimmune condition is Alopecia areata (sudden unpredictable hair loss)¹¹. 
• Iron and Ferritin level: Ferritin is a protein that stores iron. Low serum ferritin levels are significantly associated with alopecia specially in pre-menopausal women, making it crucial to test and manage ferritin levels during hair loss. Studies indicates that low iron stores are an independent factor contributing to this type of hair loss in women who haven’t reached menopause^6,12.  
• Vitamin and Mineral test: Studies⁴ have shown a low level of vitamin in people with alopecia which means alopecia can be due to deficiency of vitamins. Thus, Vitamin B12, biotin, D, C and zinc test are some essential blood tests to rule out alopecia¹³. 

Other Tests to Determine the Cause of Hair Loss 

• Medical History and Scalp Examination: This is the most basic step to rule out alopecia where a physician takes detailed history on how you take care of your hair and scalp, your diet pattern, level of stress, medical and family history.  Scalp is examined to see texture of hair, pattern of hair loss and to see any signs of infection like redness or inflammation¹. 
• Hair Pull Test: Hair pull test offers a rough assessment of active hair shedding. It is performed by gently pulling a small bundle of hair from three different areas of the scalp. If fewer than three hairs are extracted during the test, the result is considered negative (normal shedding) and if more than six strands of hair are extracted, it suggests excessive or active hair loss, resulting in a positive test¹⁴. 
• Scalp Biopsy: A scalp biopsy is a critical diagnostic tool for hair loss, to see the living tissue. It involves taking a small sample of the scalp to examine under a microscope, which helps the doctor identify the cause of alopecia. Biopsy gives clues about the patient’s prognosis specifically, if the hair loss is due to inflammation, it can be reversed or slowed down in some cases by proper treatment. To get the best result, the biopsy should typically be taken from the leading edge of the affected area, where hair loss is actively occurring. Area with complete, long-term baldness is usually avoided, as there is little active tissue left to study¹⁴.  
• Trichoscopy: Also known as scalp dermoscopy, it is a non-invasive method for evaluating hair loss. This technique uses magnification to visualize the hair shafts and scalp skin in detail using a handheld dermoscope or a videodermoscope¹⁵. 

Hair Loss Treatment Options

Treating hair loss is highly personalized and depends on the specific cause. Treatment can range from non-invasive topical applications to surgical procedures. Commonly used options are: 

1. For Management of Common Underlying Conditions

• Antifungals: If hair fall is linked to ringworm of any fungus, it is usually treated by antifungal shampoos or oral medicine for the same¹. 
• Corticosteroids: Topical corticosteroids are used for autoimmune conditions like alopecia areata¹⁶. 
• Vitamin and Mineral Supplements: Supplements are recommended if a specific deficiency is identified as contributing factor of hair loss e.g. deficient specific vitamins, biotin, zinc supplements)¹  

2. Alopecia Medications

• Topical: These are applied directly on the scalp to stimulate hair growth. For example, Minoxidil. It is used to promote hair growth and slow the progression of balding, and it is effective mainly for recent hair loss in people younger than 40. It comes in the form of liquid which is applied directly on the scalp¹⁷. 
• Oral Medications: These include drugs like Finasteride that control male pattern hair loss by inhibiting the production (Testosterone to Dihydrotestosterone) of a specific male hormone in the scalp that is responsible for halting hair growth¹⁸. It comes in form of a tablet to take orally. 
• Hair Transplant: It is a surgical procedure that improves baldness by moving hair from areas of thick growth to the bald areas. This procedure cannot produce new hair; it can only transplant the hair you currently have to the areas of baldness¹⁹. 
• Low Level Laser Therapy (LLLT) and Platelet Rich Plasma therapy (PRP): It helps in promoting hair growth by stimulating the cells within the hair follicle. Platelet rich plasma encourages hair growth by utilizing patients own blood platelets. For an effective outcome combination of LLLT and PRP is given together²⁰. 

How to Prevent Hair Loss?

By focusing on certain factors, you can effectively minimize hair loss to some extent. 

• Focus on Diet: Nutrient deficiency is one major factor that can lead to hair loss. Focus on a diet rich in iron, protein, zinc, biotin, omega-3 fatty acids, and vitamin C, which are found in foods like eggs, green leafy vegetables, nuts, meat, salmon and citrus fruits⁴. 
• Avoid Chemicals and Excessive Heat: Chemicals used for straightening and colouring hairs can cause certain side effects like allergy, chemical burns on scalp, breakage of hair further leading to alopecia. Hair styling like curling and straightening also worsens the hair condition²¹. 
• Avoid Stress: Stress hormones damage the stem cell required for hair growth. You can effectively manage stress by practicing relaxation techniques like yoga and meditation²². 

Some routine hair care tips to follow²³: 

• Wash your hair regularly. 
• Choose a shampoo and conditioner that suits your hair type. 
• Use a scalp exfoliator to remove dead skin build-up. 
• Avoid sharing personal items like hairbrushes and combs. 
• Brush your hair often to prevent tangles. 

By practicing these above steps, you can significantly minimize hair loss and promote healthier hair growth. If you still face hair fall even after taking all preventive measures, consult a doctor for regular blood tests to avoid issues that can lead to further hair loss. 

When to See a Doctor?

You need to consult your doctor if you see any of the following symptoms¹ 

• Hair loss more than usual or in a typical pattern. 
• Experiencing rapid hair loss at an early age (teen or in twenties) 
• If you see any redness, scaly texture or if you have pain on the area of hair loss. 
• Woman with a male pattern baldness. 
• Developing bald spots on eyebrows or beard. 
• Any signs of infection on the scalp. 

Early diagnosis can help to rule out the condition and prevent further hair loss. 

Conclusion

Hair loss is a condition that is quite frustrating at the same time can often be managed effectively once the root cause is identified. Diagnostic tools, especially blood tests, play an indispensable role by finding out internal imbalances like thyroid issues, hormonal changes, or nutritional gaps. Early, accurate diagnosis guides the selection of the most effective treatment, whether it’s a simple dietary supplement, a topical medication, or a more evolved procedure. If you notice rapid or unusual changes in your hair volume, consulting a doctor for comprehensive testing is the most constructive step you can take to understand and properly manage your condition. 

Frequently Asked Questions (FAQs)

References

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