Thyroid Hair Fall: Signs, Pictures & Will It Grow Back?

Hair fall can sometimes be an early sign of an underlying thyroid disorder, but identifying the connection is not always straightforward. Changes in hair density often develop gradually, and similar symptoms can occur with iron deficiency, stress, nutritional deficiencies or genetic thinning. 

Some people may also notice unexplained fatigue, weight changes or increased sensitivity to cold or heat without immediately connecting these symptoms to thyroid function. 

Understanding the signs, the role of thyroid testing and the expected recovery process can help identify the cause of thyroid hair fall and guide timely medical care.

Does Thyroid Cause Hair Fall?

Yes, thyroid dysfunction can cause hair fall, particularly when thyroid hormone levels remain abnormal for a prolonged period. Both hypothyroidism and hyperthyroidism can disturb the hair growth cycle, leading to increased hair fall across the scalp.

In hypothyroidism, low thyroid hormone levels can affect follicle activity and contribute to telogen effluvium, a condition in which more hair follicles enter the resting phase. Similar diffuse hair fall can occur with hyperthyroidism, although the underlying effects on hair follicles may differ.

A 2024 retrospective study involving 500 women with telogen effluvium examined the association between thyroid dysfunction and hair fall severity. The researchers reported the following findings:

• 150 women (30%) had hypothyroidism.

• 102 women (20.4%) had hyperthyroidism.

• Hair fall was significantly more severe among women with hypothyroidism than among those with normal thyroid function or hyperthyroidism.

What Does Thyroid Hair Fall Look Like?

Thyroid hair fall usually appears as a general reduction in density across the scalp rather than a sharply defined bald patch. These are the common changes in your hair that you can notice when you have thyroid-related hair fall:

• More scalp showing through across several areas rather than one isolated spot.

• Increased hair coming out during washing or brushing.

• A thinner ponytail or reduced overall volume.

• Dry, coarse, brittle strands in hypothyroidism.

• Softer, finer hair with increased shedding in hyperthyroidism.

• Thinning of the outer third of the eyebrows in some people with hypothyroidis
  

  

  
  .

Why Does Thyroid Dysfunction Affect Hair?

Thyroid hormones influence hair-follicle growth, metabolism, and cycling. So abnormal hormone levels can alter the balance between active growth and resting phases.

Research suggests that scalp follicles are sensitive to changes in thyroid hormones, and the these effects can differ depending on whether thyroid hormone levels are too low or too high:

• In hypothyroidism, reduced thyroid hormone activity may slow cell division and delay follicles from returning to the active growth phase. 

• Clinicians also recognise hyperthyroid-related hair fall, although its exact mechanism is less clearly understood.

This helps explain why the hair changes are often delayed. The trigger may occur first, while visible thinning appears weeks or months later.

What is the Difference Between Hypothyroidism Hair Fall vs Hyperthyroidism Hair Fall?

Hypothyroidism and hyperthyroidism can both cause hair fall across the scalp, but they may differ in hair texture, growth patterns and associated symptoms. Hypothyroidism commonly causes dry, coarse hair, while hyperthyroidism may make hair finer and softer.

The table below compares the characteristic changes associated with each thyroid condition:

Note: These signs are not diagnostic on their own. Hair texture and scalp appearance vary considerably, and some people may show few external changes despite abnormal thyroid function.

How Is Thyroid-Related Hair Fall Diagnosed?

Thyroid-related hair fall is diagnosed through a scalp examination, a review of symptoms and medical history, and thyroid function tests. A dermatologist assesses the pattern of thinning, while blood tests help confirm whether thyroid hormone levels are abnormal.

The following tests may be recommended based on the symptoms and clinical findings:

• TSH (Thyroid-Stimulating Hormone): Usually the first test used to assess thyroid function. Abnormal levels may indicate an underactive or overactive thyroid.

• Free T4 (Thyroxine): Measures circulating thyroid hormone and helps confirm hypothyroidism or hyperthyroidism when interpreted alongside TSH.

• Free T3 (Triiodothyronine): May be recommended when hyperthyroidism is suspected, particularly if TSH is low but free T4 remains normal.

• Thyroid antibodies: Help identify autoimmune thyroid conditions, such as Hashimoto's thyroiditis or Graves' disease, when clinically indicated.

• Additional blood tests: A complete blood count, serum ferritin or selected vitamin tests may be recommended if nutritional deficiencies are also suspected.

Important: The British Thyroid Foundation notes that thyroid-related hair thinning may occur alongside iron deficiency. Identifying both conditions is important because correcting thyroid hormone levels alone may not resolve hair fall caused by an additional nutritional deficiency.

How to Stop Hair Fall Due to Thyroid Problems?

The most effective way to manage hair fall due to thyroid is to treat the underlying thyroid disorder and restore thyroid hormone levels to the appropriate range. Medical treatment helps normalise the hair growth cycle, although visible hair recovery may take several months.

The treatment depends on the type of thyroid dysfunction based on which the right medication is prescribed:

• Hypothyroidism: Doctors usually prescribe levothyroxine to replace insufficient thyroid hormone. The dose is adjusted according to thyroid function tests and individual health needs.

• Hyperthyroidism: Treatment may involve antithyroid medicines, radioactive iodine or surgery, depending on the cause and severity of the condition.

Alongside medical treatment, appropriate scalp care and nutrition can help maintain hair health. The following steps may help reduce additional hair fall and protect fragile hair strands:

• Take medicines as directed and attend recommended follow-up tests to monitor hormone levels.

• Check for nutritional deficiencies. Discuss iron and ferritin testing with your doctor if hair fall continues despite thyroid treatment.

• Maintain a balanced diet, including protein-rich foods such as dal, eggs, paneer and fish, along with vegetables and iron-rich foods.

• Avoid tight hairstyles, excessive heat styling and harsh chemical treatments that can damage fragile strands.

• Do not take iodine or thyroid-support supplements without medical advice, as excessive iodine can worsen certain thyroid conditions. The British Thyroid Foundation cautions that iodine supplements can aggravate some thyroid disorders and interfere with appropriate management.

Note: You could experience temporary hair shedding during the first 4 to 8 weeks of starting Levothyroxine.

Will Hair Grow Back After Thyroid Hair Fall?

Yes, hair usually starts recovering once thyroid hormone levels return to the appropriate range with treatment. However, thyroid hair fall recovery is gradual, and visible improvements in hair density may take several months.

The American Academy of Dermatology notes that treating thyroid disease can help reverse associated hair thinning. The British Thyroid Foundation also reports that hair recovery is common after successful thyroid treatment, although some people may experience incomplete recovery.

Hair follicles need time to return to their normal growth cycle, even after thyroid blood tests improve. Hair loss may begin to decrease before new strands grow long enough to increase overall hair volume. Persistent thinning may require further assessment for other causes, such as iron deficiency or genetic hair thinning.

How Can You Track Thyroid Hair Recovery Through Pictures?

Photographs can help track changes in hair density during thyroid treatment, especially when improvements develop gradually. Comparing pictures taken over several months may help you notice changes in scalp coverage, parting width and overall hair volume.

What Do Thyroid Hair Fall Pictures Usually Show?

Thyroid hair fall pictures commonly show reduced hair density, a wider-looking parting and greater scalp visibility. Thinning generally affects multiple areas rather than appearing as sharply defined bald patches.

To monitor changes accurately, you should take consistent photos and maintain this routine:

• Capture the same angles.Take pictures of the front, crown, sides and central parting.

• Photograph your hair under similar lighting conditions to avoid misleading differences.

• Use the same parting and compare hair when similarly dry.

• Take monthly pictures. Allow enough time between photographs to observe gradual changes.

Traya’s Perspective on Thyroid Hair Fall

Thyroid-related hair fall requires medical treatment to bring thyroid hormone levels under control. However, some people may continue to experience hair fall due to additional factors such as iron deficiency, inadequate nutrition, or genetic hair thinning. It is possible to identify these factors with a root-cause approach which diagnoses hair fall.

Traya follows a personalised 3-Science approach that combines Hair Science, Ayurveda, and Nutrition. Hair Science assesses hair thinning patterns, scalp health, and suitable treatment options. Ayurveda contributes to Traya's broader hair-care approach, while Nutrition focuses on dietary habits and nutritional deficiencies that may affect hair health.

Traya's Hair Test helps assess individual hair fall concerns and possible contributing factors. Based on the assessment, a personalised plan may include nutritional guidance, scalp care and doctor-recommended hair treatments where appropriate. Thyroid medication and hormone monitoring must continue under the supervision of a qualified doctor, as hair-care treatments cannot correct thyroid dysfunction.

Frequently Asked Questions

1. Can hypothyroidism cause hair fall even if TSH is only mildly abnormal?

It can, but mild thyroid abnormalities do not always explain noticeable hair fall. The British Thyroid Foundation notes that significant hair changes are more commonly linked with severe or prolonged thyroid dysfunction. Consider other causes when the thyroid abnormality is minor.

2. How long does thyroid hair fall last?

Thyroid hair fall may last for several months because the hair cycle responds slowly to hormonal changes. Even after thyroid levels improve, hair fall may take 1-2 months to settle, and visible density may recover later.

3. Can thyroid medication initially make hair fall look worse?

Yes, it can. Because hair-cycle changes occur with a delay, hair fall may become noticeable after treatment begins even though the thyroid disorder started months earlier. This can make the medication appear responsible when the earlier hormone imbalance may actually be the trigger.

References

• Dayel, S. B., et al. (2024). Is thyroid dysfunction a common cause of telogen effluvium? A retrospective study. Medicine, 103(1), e36803. 

• American Academy of Dermatology Association. Thyroid disease: A checklist of skin, hair, and nail changes. 

• van Beek, N., Bodó, E., Kromminga, A., Gáspár, E., Meyer, K., Zmijewski, M. A., Slominski, A., Wenzel, B. E., & Paus, R. (2008). Thyroid hormones directly alter human hair follicle functions: Anagen prolongation and stimulation of both hair matrix keratinocyte proliferation and hair pigmentation. The Journal of Clinical Endocrinology & Metabolism, 93(11), 4381–4388. 

• Contreras-Jurado, C., Lorz, C., García-Serrano, L., Paramio, J. M., & Aranda, A. (2015). Thyroid hormone signaling controls hair follicle stem cell function. Molecular Biology of the Cell, 26(7), 1263–1272.

• Contreras-Jurado, C., Lorz, C., García-Serrano, L., Paramio, J. M., & Aranda, A. (2015). Thyroid hormone signaling controls hair follicle stem cell function. Molecular Biology of the Cell, 26(7), 1263–1272. https://doi.org/10.1091/mbc.E14-07-1251 Cited by: 66

• British Thyroid Foundation. (n.d.). Hair loss and thyroid disorders. https://www.btf-thyroid.org/hair-loss-and-thyroid-disorders

• van Beek, N., Bodó, E., Kromminga, A., Gáspár, E., Meyer, K., Zmijewski, M. A., Slominski, A., Wenzel, B. E., & Paus, R. (2008). Thyroid hormones directly alter human hair follicle functions: Anagen prolongation and stimulation of both hair matrix keratinocyte proliferation and hair pigmentation. The Journal of Clinical Endocrinology & Metabolism, 93(11), 4381–4388. https://doi.org/10.1210/jc.2008-0283 Cited by: 217

• Wang, S., Zhang, Y., & Li, X. (2024). Is thyroid dysfunction a common cause of telogen effluvium? A retrospective study. Medicine, 103(1), Article e36803. https://doi.org/10.1097/MD.0000000000036803

Read More Blogs

Can Androgenetic Alopecia Be Reversed or Cured?

Quick Answer Androgenetic alopecia cannot be permanently cured because inherited sensi...

Which Vitamin and Nutrient Deficiency Causes Hair Fall? Vitamin D, B12, Zinc & More

Quick Answer The most common micronutrient deficiencies linked to hair fall are Vitami...

Iron Deficiency & Low Ferritin Hair Fall: Levels, Tests & Recovery

Quick Answer Low ferritin and iron deficiency can contribute to diffuse hair fall b...

Stress, Sleep & Hormonal Hair Loss: Causes and Recovery

Quick Answer Stress, lack of sleep, and changing hormone levels throw off your hair's ...