Hair Loss can have Multiple Causes
Thyroid issues, particularly hypothyroidism, are one of the possible causes of your hair loss complaints. This blog will discuss the role of thyroid hormones in hair growth, the various types of hair loss associated with hypothyroidism, and potential therapies for your condition.
Hair Cycle
Terminal hair follicles and vellus hair follicles are the two main types of hair follicles on your skin. Terminal hair follicles are larger and extend into the subcutaneous fat, whereas vellus hairs are short and fine.
Once hair follicles have developed, they follow a life cycle including growth periods (Anagen), transformation (Catagen), and rest periods (Telogen).
- Anagen phase: This is the growth phase, which means your hair is actively developing. Approximately 90% of scalp hair follicles are in the anagen phase at any given time.
- Catagen phase: The hair subsequently enters the “transition phase,” during which the lower part of the hair follicle regresses and hair production ceases. Catagen on the scalp lasts around three weeks on average and is present in less than 1% of follicles on the scalp.
- Telogen phase: Also known as the resting phase, it occurs after catagen and lasts two to three months on the scalp. Up to 10% of follicles are normally in Telogen stage that are ready to shed from the hair follicle.
- The Telogen phase is followed by the Anagen phase, which results in new hair growth.
Understanding this simple process is critical to understanding how thyroid problems and a variety of other medical issues can impact your hair.
Thyroid Hormones Effect on Hair Follicle Cycling and Pigmentation
Thyroid hormones (THs) play a significant role in the formation and maintenance of hair follicles through their direct impact on hair follicle cycling. T3 and T4, for example, raise the number of anagen hair follicles while decreasing the number of catagen hair follicles, which prevent apoptosis in these cells. Moreover, T4 promotes keratinocyte proliferation in the human hair matrix.Â
Hair Loss and Hypothyroidism
Thyroid hormone deficiency can result in altered hair/skin structure and function, as well as the appearance of dry, brittle, and dull hair shafts, especially in untreated or severe cases.Â
Inadequate amounts of thyroid hormones (T3 and T4), for example, cause the Telogen phase to be prolonged, resulting in a failure of follicles to reenter anagen, causing a reduction in hair density and increased shedding. Telogen effluvium is a disease in which this happens.
Hair Loss Associated with Medicines of Hypothyroidism!
Signs and Symptoms of Thyroid-Related Hair Loss
Every day, we all shed 50–100 hairs from our bodies as part of the regular hair growth cycle. This hair loss is completely natural and will be replaced over time. However, if the thyroid does not generate enough T4 and T3 hormones, more follicles will enter the resting phase, causing the regrowth cycle to be disrupted. That is, you may notice thinner hair over time, which may progress to noticeable hair loss without replacement.
Hair loss often affects the entire scalp rather than a specific location, and it can affect hair on any part of the body, including eyebrows and eyelashes.
The loss of hair on the Outside 1/3 of your eyebrow is a classic sign that has been linked to hypothyroidism-related hair loss.
As you see in this picture
The symptoms and signs of the condition vary depending on the severity and duration of hypothyroidism. Some of the signs of thyroid-related hair loss and hair changes are as follows:
- Â Diffuse alopecia across the whole scalp (71.35%)
- Â Alopecia areata (11.8%), Hair loss that occurs in discrete areas of the scalp, resulting in smooth, circular bald patches
- Â Androgenetic alopecia (14.29%).
- Â Uniform hair thinning or loss of hair density
-  Changes in hair texture that become dry or coarse
- Â Telogen Effluvium
-  Thyroid conditions such as hypothyroidism don’t only affect the hair but also result in a range of other symptoms of decreased hormone secretion.
- Â Hair loss associated with autoimmune thyroid disease
- Most people with hypo- or hyper-thyroidism with an autoimmune etiology could be associated with other autoimmune conditions such as Alopecia areata that cause hair loss.
- Alopecia areata (AA) is an autoimmune condition that causes non-scarring hair loss commonly associated with various autoimmune disorders like autoimmune thyroid disease. Unlike diffuse hair loss type described above, alopecia areata causes small, discrete and circular, areas of hair loss.
- Even in the absence of clinical symptoms suggestive of hypothyroidism in a condition called subclinical hypothyroidism, you could also suffer from Alopecia areata.
- Â If you have symptoms of hair loss in a picture of Alopecia Areata, you should be tested for thyroid functions and thyroid autoantibodies.
Estrogen and Progesterone Role in Hair Growth
- Â Excess estrogen raises your thyroid-binding globulin (TBG) levels. TBG is a protein, which allows your thyroid hormones to travel in the circulation. However, thyroid hormones are inactive when linked to TBG. As a result, T4 cannot be stored in your tissues or converted to Free T3, resulting in hypothyroid symptoms such as thyroid hair loss.
- Â Progesterone can influence hair follicle growth through central and local action. The central action acts as an inhibitory effect on LH secretion, which in turn causes a decrease in ovarian theca cell stimulation (androgen synthesis). At the level of the hair follicle, progesterone decreases the conversion of testosterone to DHT decreasing androgenic hair loss.
Androgenic Alopecia
Androgenetic alopecia is the most common form of alopecia in men and women that affects roughly 50% of men and perhaps as many women older than 40 years. Androgenic alopecia, which is a hereditary condition that results in the progressive change of big, thick, pigmented terminal hairs into thinner, shorter, non pigmented vellus hairs.Â
If you have an Androgenic alopecia, your hair loss will often appears on the top and frontal region of the scalp and progressively recedes. This form of hair loss is related to hormones called androgens, particularly excessive dihydrotestosterone (DHT) activity.
How do we Know if Hypothyroidism is Responsible for your Hair Loss?
- Â Interestingly, evidence has shown that hair loss can occur in thyroid disorders other than hypothyroidism, including hyperthyroidism, Hashimoto’s thyroiditis, and Graves’ disease.
- Â If you are experiencing new-onset diffuse hair loss or have a history of hypothyroidism and are concerned that you may be suffering from thyroid-related hair loss, the best strategy is to consult with your healthcare provider doctor about your symptoms.
- Based on your history and physical examination, as well as some laboratory testing, your doctor will determine what is causing your hair loss.
- Â Androgenetic alopecia is usually diagnosed clinically with a history of gradual onset, occurring after puberty, and a family history of baldness. In addition ,thyrotropin level could be ordered If a thyroid disorder is suspected
- Food allergies may be associated with hair loss especially if the allergy has resulted in nutritional deficiencies or an accompanying autoimmune disease.
- It is uncommon for thyroid disease to induce hair loss in the absence of other signs of an overactive or underactive thyroid. Before making a diagnosis, your doctor will rule out other possible causes of hair loss, such as androgenetic alopecia ,nutritional deficits and drug side effects.
- Â An initial laboratory evaluation will focus on identifying potential causes that could cause hair loss. Suggested initial laboratory tests for the primary care setting include thyroid stimulating hormone to assess for thyroid disease as well as serum iron and ferritin to assess for iron deficiency or iron overload as a cause of hair loss. If the thyroid cause has been excluded, other tests could be performed according to your condition.
- This table summarizes some of the blood tests that should be ordered to determine the cause of your hair loss, which include the following:
Is Hair Loss Caused by a Thyroid Condition Reversible?
- Â This is dependent on the type of thyroid disease. If the cause is solely hormonal (such as hypothyroidism), your hair generally grows back after normal thyroid levels are restored. However If the hair loss is caused by an autoimmune illness, such as Hashimoto’s disease, which attacks the thyroid, subsequently autoimmune hair loss, such as Alopecia Areata, may be irreversible.
- Â If you’ve had hypothyroidism symptoms associated with hair loss, and have been treated with medications to bring your thyroid back into balance but still have hair loss, your doctor may investigate alternative diagnoses, such as androgenic alopecia, in which testosterone is converted to DHT, causing hair loss.
How to Treat Thyroid-Related Hair Loss?
-  The good news is that once you’ve been diagnosed with hypothyroidism and either natural products like Armour or synthetic thyroid hormone treatments such as, Levo-T® , Synthroid®, Cytomel(T3 medicine) or combined medicines for T4 and T3 have been prescribed to rebalance your thyroid hormones, the problem of hair loss should go away on its own. However, hair regrowth may take several months after treatment as On the scalp, the growth rate of terminal hair is approximately 0.3 mm per day and the duration of anagen ranges from two to six years.
- Â If you are unhappy with the appearance of your hair while treatment is taking place, select a hairstyle that will fit the thinning hair and will help hide hair loss. Also, avoid stressing your hair by using heat styling, braiding, or chemical treatments.
- Â Manage your stress: Stress produces changes in the levels of a hormone called Cortisol. Cortisol is not only linked to abnormal thyroid levels, but it is also a cause of natural hair growth impairment.
- Â A balanced diet, in addition to taking the prescribed thyroid medicines, can assist to encourage hair growth. Among the foods that can help you have stronger hair are:
- Â Fish: Oily fish contains omega-3 fatty acids that can help prevent a dry scalp.
- Â Green vegetables: Vegetables such as spinach have high levels of vitamins A and C, which can improve the health of hair.
- Â Biotin-rich foods: Biotin is a vitamin that is important for hair growth. Sources of biotin include whole grains, liver, egg yolk and yeast. Biotin is also available in many over-the-counter (OTC) hair vitamins.
- Protein-rich meals: Eating Protein-rich food can help prevent hair from becoming weak and brittle. Protein is found in dairy products, nuts, and lean organic, collagen from grass-fed cows to take with a whey protein drink with berries.
- Foods high in calcium: Calcium is essential for hair development. Dairy products, such as milk and cheese, are good sources of calcium.
- Take a high quality Multivitamins to support thyroid function such as zinc, Selenium Vitamins B complex: B7, C, E, A, D-3, B-12.
- Take a daily iron supplement: iron deficiency is a common cause of thyroid related hair loss in premenopausal women.
- Essential oils, such as eucalyptus oil, castor, olive oil and other plant extracts, can help to decrease hair fallout and enhance hair density.
- It is critical to consult with your doctor before starting to use oils, and to proceed with caution when selecting a high-quality brand.
- Your doctor may also suggest you try Minoxidil (Rogaine) drug : This is a topical solution that is applied to improves blood flow to the scalp so that to promote more rapid hair growth
- Oral 5-alpha-reductase inhibitors, such as finasteride, can effectively slow or even reverse androgenic Alopecia. Finasteride, as well as minoxidil, are FDA approved for the treatment of androgenetic alopecia.
Recovery from the Hair Loss
Conclusion
References
- Bakry, O. A., Basha, M. A., El Shafiee, M. K., & Shehata, W. A. (2014). Thyroid disorders associated with alopecia areata in Egyptian patients. Indian journal of dermatology, 59(1), 49.
- Taguchi, T. (2018). Brittle nails and hair loss in hypothyroidism. N Engl J Med, 379(14), 1363.
- Van Beek, N., Bodo, E., Kromminga, A., Gáspár, E., Meyer, K., Zmijewski, M. A., … & 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.
- Freinkel, R. K., & Freinkel, N. (1972). Hair growth and alopecia in hypothyroidism. Archives of dermatology, 106(3), 349-35
