In this article:
The thyroid gland is a butterfly-shaped endocrine organ that lies on the front side of your lower neck and is controlled by the hypothalamus and pituitary gland in the brain.
This gland converts iodine derived from foods into two types of hormones, namely, triiodothyronine (T3) and thyroxine (T4). Both these thyroid hormones play a critical role in various life-sustaining body functions, such as metabolism, neurological and physical development, and the working of various organs such as the brain, heart, muscles, and liver.
Any problem with this gland can negatively impact the entire body and can lead to several health problems.
There are basically two types of thyroid dysfunction:
- An overactive thyroid gland secretes excessive hormones, known as hyperthyroidism.
- An underactive thyroid gland fails to produce enough hormones, known as hypothyroidism.
This article will discuss the link between thyroid dysfunction and hair loss.
Structure of a Hair Follicle
Human hair grows out of a tunnel-like structure called a hair follicle, which is embedded into the skin (dermis). These follicles are present all over the body, but they are most densely concentrated on the scalp, which contains nearly 100,000 follicles on average.
A hair follicle starts as a tiny pore on the epidermis and extends like a narrow canal deep into the dermis. A sebaceous gland underlying the scalp is attached to the upper part of the follicle from the outside. This gland supplies oil or sebum to the hair follicle to keep the hair naturally moisturized.
The lower end of the follicle is onion shaped and called the hair bulb. It is here that living hair cells called keratinocytes proliferate to construct the hair shaft.
The hair bulb is surrounded by the dermal papilla, which is enriched by several blood vessels that supply nutrients, oxygen, and essential hormones to sustain hair cell division and thereby healthy hair growth.
Hair growth cycle
Hair growth occurs in four phases that proceed into a cycle:
- Anagen phase – The hair cells divide and multiply to make the hair grow long and sturdy.
- Catagen phase – The hair root becomes clubbed and receives no more hair cells or blood supply, marking the end of active hair growth.
- Telogen phase – This resting phase is characterized by the gradual weakening of the hair shaft.
- Exogen phase – This final phase is marked by the shedding of the fully grown hair to make room for a new one.
How Does a Thyroid Disorder Cause Hair Loss?
Thyroid hormones interact with the hair follicles to affect hair growth. (1) A dysfunctional thyroid gland can hamper the functioning of the papillae, leading to diminished blood supply to the hair bulb.
The lack of nourishment shrinks the hair follicle and pushes it into an early resting phase. As a result, the nutrition-deprived hair becomes progressively weak and thin until it falls out. (2)
This kind of premature hair shedding is called telogen effluvium. The good thing is it can be reversed with proper treatment. (3)
Only severe or chronic thyroid dysfunction is associated with hair loss. Mild or short-lived thyroid dysfunction rarely triggers hair loss.
Autoimmune disorders such as Hashimoto’s disease, lupus, polycystic ovary syndrome, alopecia areata, and Graves’ disease are characterized by thyroid dysfunction and therefore increase the risk for hair loss and balding. (4)(5)
Although thyroid-related hair loss is usually temporary, some of these autoimmune disorders such as lupus can lead to permanent bald patches or hair thinning.
Note: In some cases, the hair loss is not caused by the thyroid dysfunction itself but by the medications used for treating it. Drugs such as levothyroxine, propylthiouracil, and carbimazole are known to trigger hair thinning as a side effect. (6)
Nevertheless, such hair loss only occurs during the first 1–2 months of the treatment and tends to resolve once the hormones balance out. This points to the importance of understanding the root cause of your hair loss before you try to treat it.
Pattern of Thyroid-Related Hair Loss
Thyroid-related hair loss manifests in the form of gradual hair thinning rather than a sudden appearance of bald patches.
This hair thinning is not limited to the scalp but can occur in other areas of hair growth as well, such as the eyebrows (a symptom of hypothyroidism).
If this thyroid-related hair fall is left untreated, the hair volume will decrease over time and eventually will result in bald patches.
Hair loss caused by a thyroid disorder usually occurs in the following patterns: (7)
- Eyebrows become sparse on the outer edge.
- Hair may become rough, dull, dry, and brittle.
- Soft and fine hair sheds easily.
- The rate of hair growth is extremely slow.
- The legs, arms, and other areas have minimal to no hair growth.
Medical Treatment for Thyroid-Related Hair Loss
The medical treatment for thyroid-related hair loss involves correcting the underlying thyroid dysfunction.
Hyperthyroidism causes an excess of thyroid hormones, whereas hypothyroidism causes a deficit of thyroid hormones. Both hormonal imbalances can impede hair follicle function and thereby hamper hair growth.
The doctor will first determine the exact thyroid problem and then recommend the appropriate measures to address it.
1. Treatment for an overactive thyroid
Hyperthyroidism is usually treated with internal radiation therapy using radioactive iodine and thyroid suppressors such as methimazole and beta blockers. Severe cases may require surgical removal of the thyroid gland.
2. Treatment for an underactive thyroid
Hypothyroidism is usually treated with medications such as levothyroxine.
3. Hair loss treatment
The above standard treatments will help control future hair thinning by restoring proper thyroid function, but you’ll need additional medications to recover the hair already lost.
Minoxidil is the only FDA-approved medication for hair growth and is generally available without a prescription. A newer treatment modality called nanoxidil has a similar mechanism to minoxidil, but it is more of a cosmeceutical than a pharmaceutical agent.
Finasteride (prescription medication for male-pattern baldness), platelet-rich plasma therapy, multinutritional supplements to boost hair growth, mesotherapy, growth factors and peptide sprays, low-level laser treatment, and hair transplant surgery are also some ways to treat hair loss.
But bear in mind that none of these treatments will provide instantaneous results because hair growth is a long process. It will take several months for your hair to grow back to a full density, but even then it may not be as thick as before. The new hair may also have an uneven texture and color.
No matter how effective the treatment, it is very difficult to reverse the hair loss completely. However, starting treatment in the early stages of the disease when the hair loss is minimal will make it easier for you to regain most of your hair volume.
Diagnosing the Cause of Hair Loss
To treat hair loss, you must first understand what exactly is causing it. It can be a sign of a wide range of underlying conditions such as thyroid disorders, androgenic alopecia, nutritional deficiencies, and menopause. All these conditions induce hair loss through different mechanisms and therefore require different treatments.
So, your doctor will properly evaluate your condition, symptoms, medical history, and hair loss pattern to reach a conclusive diagnosis.
Thyroid disorders trigger many symptoms, but hair loss is not one of the first ones. It sets in much later, so catching and treating the disorder early can help avoid the hair loss altogether.
Thyroid disorders are usually diagnosed through a blood test that determines the concentration of thyroid-stimulating hormone (TSH) in the body. (2)
Thyroid-Related Hair Loss vs. Androgenic Alopecia
Thyroid dysfunction is characterized by an excess or lack of thyroid hormones, whereas androgenic alopecia is marked by abnormally high levels of androgens or male sex hormones in the body. Thus, both these conditions are characterized by hormonal imbalance, but different hormones are involved.
In hypothyroidism and hyperthyroidism, the resting phase of the hair cycle is prolonged, whereas in androgenic alopecia, dihydrotestosterone (DHT) shortens the growth phase (anagen phase) of the hair cycle.
The hair loss pattern of these two conditions is also starkly different, which makes it easier for the doctor to distinguish between the two.
Hair loss associated with thyroid disorders usually begin from the scalp but can extend to other regions, whereas androgenic alopecia is limited to specific portions of the scalp, such as the vertex.
Natural Solutions for Hair Loss
Several natural remedies, including hair-stimulating agents, oils, and supplements, can help fight hair loss by strengthening the hair follicles and promoting hair regrowth. These remedies can be incorporated into your hair care regimen.
But bear in mind that these remedies are not magic bullets that will stop or reverse your hair fall with a few uses. You must use them consistently for months in the correct manner to see good results.
Also, these therapies are typically recommended for general hair loss and may have no effect on the underlying thyroid problem. So there’s a good chance that they might not deliver the expected results or even trigger untoward effects by reacting with your thyroid treatment.
Therefore, it is best to consult your doctor before using any of these remedies, especially before starting any oral supplement.
Caution: Conduct a patch test before using a new topical hair remedy to make sure you are not allergic to any of the following ingredients used.
Note: Biotin supplements may influence the concentration of TSH in your blood. So, if you are going for a TSH test, discontinue the supplement a week before the test to avoid an incorrect reading. Besides, you must always inform your doctor about the supplements that you are taking.
Adopt the following self-care measures along with the standard treatment to reduce thyroid-related hair loss:
- Give yourself a regular head massage with a therapeutic hair oil to promote faster and healthier hair growth. The gentle topical stimulation enhances blood circulation in the scalp, which brings more nutrients and oxygen to the hair follicles. Well-nourished hair follicles will inadvertently produce thick, strong hair. The hair oil also helps hydrate and nourish your scalp and hair. (18) Coconut oil, Jamaican black castor oil, olive oil, and argan oil are some of the most recommended oils for hair growth. You can either use a single hair oil or blend it with another. You can even add a few drops of any of the above-listed essential oils to your hair oil. Slightly warm your hair oil or oil blend to facilitate better application and absorption. Oil your hair two to three times every week for a few months to see visible improvement.
- You can try wigs, hair extensions, or new hairstyles to cover the areas with sparse hair or bald patches.
- Limit the use of hairstyling tools as much as possible as they subject your brittle hair to a lot of traction and heat, thus triggering further hair loss. And never use them without first applying a hair protectant, which helps shield your hair from the heat. Excessive use of these devices can burn your hair and destroy the hair follicles.
- Be gentle when brushing or combing your hair to avoid breakage. Regular combs and brushes with compact bristles tend to get stuck in your hair knots and pull at your hair roots to cause hair shedding. This can easily be avoided by using a wide-toothed brush or comb, which loosens the knots in your hair without tugging at the roots. Curly, wavy, or unruly hair are more manageable when damp, so it’s best to comb or brush it soon after a hair wash before it dries.
- Don’t use hair products that contain harsh, moisture-stripping chemicals, such as sulfates, parabens, alcohols, and formaldehyde, which can dehydrate and weaken your hair in the long run. It’s best to avoid dyes, bleaches, and other chemical hair treatments for the same reason.
- Avoid tight hairstyles, such as braids, that put a lot of strain on your hair roots and weaken them over time.
- Don’t use hot water for hair washing as it can strip away the natural lipids from your scalp and hair, making them dry. Dry hair is more prone to breakage and shedding. Use lukewarm or room-temperature water instead.
- Don’t take any “hair supplement” without running it by your doctor first. Some contain iodine, which can further disrupt your thyroid function and hinder the absorption of thyroid medication such as levothyroxine.
- Consume a well-balanced diet with foods rich in vitamin B complex, zinc, iron, coenzyme Q10, vitamins A and C, calcium, and copper as well as anti-inflammatory foods such as turmeric. Limit your intake of refined sugars, iodine, and unhealthy fats.
- The stress of losing your hair can further interfere with your hair growth cycle to trigger more hair loss and delay hair regrowth.
It is therefore very important to make peace with the problem rather than worrying about it too much. Hair thinning can adversely impact your appearance, but stressing about it will only make things worse.
Instead of fixating on this problem, try to overcome it through the available treatments. Know that many others are having the same struggle, and some may even have it far worse than you.
Make the best of the situation by trying new hairstyles that give volume to your hair and cover the balding areas. Don’t reduce yourself to this problem, and focus on the positive aspects of your personality.
If you are finding it hard to stay positive, talk to your loved ones, friends, and family or join a support group to feel less alone in the struggle.
The abundance or lack of thyroid hormones can make your hair thin, brittle, and more likely to fall out. Hair loss is one of the most common symptoms of both hypothyroidism and hyperthyroidism, but it only occurs in the advanced stages of the disease.
If you catch and treat your thyroid dysfunction early, hair loss can more or less be avoided. This is why you must educate yourself about the initial signs of thyroid dysfunction and immediately get yourself checked if you experience any of them.
For those who are already diagnosed with severe thyroid disorders, stay committed to your doctor-recommended treatment to keep the condition under control and avoid complications, such as permanent hair loss.
There are alternative remedies and therapies that you can try to promote hair growth, but they are not a replacement for your standard medication.