The Relationship Between Your Thyroid and Hair Loss

The thyroid gland is shaped like a butterfly and lies at the lower, front part of your neck. It plays an important role in regulating your metabolism, which is how our body produces energy. Every organ and system in the body needs energy to be able to function correctly. The thyroid is pivotal in keeping your body working at its best. 

When the thyroid doesn’t function properly, it can cause poor health. This can cause issues with energy, weight, temperature regulation, cognitive ability, mood, and more. Another hallmark symptom of thyroid issues is hair loss. (1,2) 

When hormone levels are out of balance, it can affect the hair follicle and how hair grows. Individuals with a thyroid condition can experience diffuse hair loss, making hair thin across the scalp, rather than causing bald patches. And alopecia areata, an autoimmune form of hair loss, is also well-known to be associated with thyroid dysfunction. Fortunately, there are many ways to treat thyroid-related hair loss, most of which involve treating the underlying condition. (3)

Your Thyroid’s Role in Health

The thyroid is a gland that makes up part of the endocrine system. The endocrine system is the network of glands in your body that produce hormones. Hormones regulate many important functions in the body, including metabolism, mood, growth, and the reproductive system. (1,2) 

The thyroid gland makes thyroid hormones, which do lots of important jobs related to the regulation of metabolism. Your metabolism allows your body to convert the food you eat into ‘fuel’, creating energy your body can use. (1,2) 

The main hormone the thyroid produces is thyroxine, also called T4. Thyroxine is called T4 because it contains four iodine atoms. T4 is converted into triiodothyronine (T3) when one of the iodine atoms is removed. These two hormones control how much energy is used and keep your metabolism functioning correctly. (1,2) 

When the endocrine system doesn’t work properly, hormone levels in the body are imbalanced. This can cause a range of health issues. There are many thyroid conditions that can cause ill health, including (1,2):

• Hyperthyroidism: A condition where the thyroid is overactive and produces too much T4. 
• Hypothyroidism: An underactive thyroid not producing enough T4. 
• Goiter: An enlarged thyroid gland that is often seen alongside other thyroid conditions.
• Thyroid Nodules: Small abnormal growths in the thyroid sometimes related to hyperthyroidism. 
• Thyroiditis: A term referring to general inflammation of the thyroid. 
• Hashimoto’s Thyroiditis: A genetic, autoimmune disorder that causes inflammation of the thyroid, affecting its ability to produce hormones. 
• Graves’ Disease: An autoimmune condition that can lead to hyperthyroidism. 
• Thyroid Cancer: A number of cancers can affect the thyroid, impacting its ability to produce thyroid hormones. 

Your Thyroid and Hair Health

Thyroid hormones T3 and T4 have a direct impact on the hair follicles. They help hair follicles develop and allow them to keep producing healthy hair. When thyroid hormones become imbalanced, they can interrupt the hair growth cycle. (3-5)

The resulting hair loss can affect both the scalp and body. It can also cause changes in hair health, causing brittle, dry, or even greasy hair. It can even affect hair pigmentation, causing early greying. (4,5) 

​​Can Thyroid Problems Cause Hair Loss? 

It’s well established that problems with the thyroid can cause hair loss. The thyroid plays a crucial role in hair growth. When the thyroid isn’t functioning correctly, it can cause hair loss on the scalp, face, and other areas of the body. (3) 

Common thyroid issues that cause hair loss include hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid). A number of conditions can lead to hypothyroidism or hyperthyroidism. (1-4) 

Parathyroid disorders can also cause hair loss. Parathyroid glands are four little glands near your thyroid. They produce hormones that control the amount of calcium in the blood. When their hormone production is imbalanced, it can cause health issues, including hair loss. (3,6) 

Pregnancy can sometimes lead to thyroid dysfunction. Thyroid issues in pregnancy are mostly caused by an autoimmune reaction. Autoimmune thyroid problems include conditions like Graves disease and Hashimoto’s thyroiditis. (7,8) 

Postpartum thyroiditis is a condition occurring after pregnancy, causing inflammation of the thyroid gland. This issue can cause either high or low levels of thyroid hormones, which can contribute to hair loss. (9) 

Many different thyroid cancers can also lead to hair loss. And of course, the cancer treatment itself can cause or worsen hair loss. Hormone replacement therapies, among other treatments, may be needed to facilitate regrowth. (10) 

Hair Loss Due to Thyroid Problems

A number of thyroid issues – including hypo- or hyperthyroidism – can lead to hair loss. Both during and after pregnancy, hormone levels are changing, which can impact endocrine function. Thyroid hair thinning and hair loss are common, along with a number of other symptoms. (2,4,7) 

Nutrient deficiencies can also impact the thyroid’s ability to produce thyroid hormones. When thyroid hormones are imbalanced, the body can struggle to absorb certain nutrients that are crucial for healthy hair growth. (2,11) 

Telogen effluvium is a type of hair loss that occurs after a physically or emotionally stressful event. It causes diffuse hair loss, which can occur at the same time as thyroid-related hair loss. Thyroid issues caused by nutrient deficiency or over-supplementation can actually be a form of telogen effluvium. (5,11,12) 

Hypothyroidism and Hair Loss

Hypothyroidism refers to any condition that causes the thyroid to be underactive and produce lower amounts of thyroid hormones. Since the thyroid gland regulates energy production in the body, this can cause the body’s processes to slow down. Symptoms include fatigue, being unable to keep warm, depression, constipation, dry skin, and hair loss. (3,13) 

Thyroid hormones help keep the hair follicle healthy and working properly. When hair follicles aren’t getting enough hormones, they can’t function as they should. This leads to hypothyroidism hair loss. (3) 

Hashimoto’s disease is an autoimmune condition that can cause hypothyroidism. It causes the body’s immune system to attack the thyroid. The thyroid can then become damaged and can’t produce enough thyroid hormone. Hashimoto’s hair loss is the result. (14) 

Polycystic ovarian disease (PCOD) is a disorder affecting a female’s hormone levels. Women with PCOD are up to four times more likely to have hypothyroidism. A comparative cross-sectional study found that this is likely due to unregulated estrogen levels stimulating an autoimmune reaction. (15) 

Treatment for hypothyroidism is thyroid replacement medication, to increase the thyroid hormone back to the right level. Unfortunately, sometimes this medication can cause or worsen hair loss. (13,16) 

Hyperthyroidism and Hair Loss

Hyperthyroidism refers to any condition that causes the thyroid to be overactive and produce excessive amounts of thyroid hormones. An overactive thyroid can lead to processes being ‘sped up’ in the body. This can cause a range of symptoms including a fast heart rate, increased sweating, weight loss, thin skin, and fine brittle hair. Hair loss is common in patients with hyperthyroidism. (3,12,17) 

Graves’ disease is an autoimmune disorder causing the body’s immune system to mistakenly attack the thyroid. This can cause hyperthyroidism. It tends to be genetic and is more commonly seen in young females. (17) 

Treatment of hyperthyroidism depends on many factors, including age and the severity of symptoms. Anti-thyroid agents, which are drugs that can reduce thyroid hormone production, are sometimes prescribed. Radioactive iodine can also be used to destroy some thyroid hormone-producing cells. Other potential treatments include beta-blockers and surgery. Hyperthyroidism hair loss will typically resolve once the condition is treated. (17) 

Thyroid Problems, Pregnancy, and Hair Loss

Thyroid issues experienced during pregnancy are typically caused by an autoimmune reaction. Graves’ disease is an autoimmune condition that can lead to hyperthyroidism in pregnancy. It causes the thyroid to produce excess thyroid hormone. This is typically treated by careful monitoring. Sometimes doctors may offer anti-thyroid medicines to reduce the thyroid hormones in the bloodstream. (7) 

Hashimoto’s disease is an autoimmune disorder that can cause hypothyroidism in pregnancy. It damages the thyroid and stops it from making enough hormones. This occurs in two to three out of every 100 pregnancies. It’s usually treated with thyroid replacement medication. (7) 

Both hypothyroidism and hyperthyroidism can lead to changes in hair texture, as well as hair loss. Telogen effluvium, a stress-related form of hair loss, can also occur in pregnancy alongside thyroid issues. (4,5) 

A thyroid condition called postpartum thyroiditis can lead to hair loss after pregnancy, among other symptoms. Postpartum thyroiditis is an inflammation of the thyroid, causing the thyroid hormone to ‘leak’ out of the gland. Initially, this can cause hyperthyroidism. Later on, it can lead to hypothyroidism. (7) 

Thyroid Problems, Diet, and Hair Loss

The calories we eat are the fuel we give our bodies to function properly. The thyroid helps convert this fuel into energy. When we don’t consume the right amount of nutrients, it can cause health issues. (1,2) 

Trace elements including zinc, copper, and selenium are needed for healthy thyroid function. The thyroid also needs iodine to produce thyroid hormones. When the thyroid doesn’t have access to enough of these nutrients, it can’t produce enough hormones. This leads to hypothyroidism. (18,19) 

Thyroid hormones are needed to help the body absorb zinc, an essential mineral. Therefore, people with hypothyroidism can experience a zinc deficiency. Other nutrient deficiencies can also lead to hair loss. When the body isn’t getting enough of the essential nutrients it needs, it can cause stress-related hair loss. (11,12,18) 

But it’s important to note that taking too many supplements can also lead to hair loss. In particular, supplements containing too much selenium, vitamin A, and vitamin E can be problematic. Having the right balance of nutrients – ideally from the foods you consume – is key. Correcting the nutrient deficiency or stopping over-supplementation will resolve this type of hair loss. (11,12)

Thyroid Problems and Other Alopecias

There are many different forms of alopecia, the more formal name for hair loss. Alopecia areata is an autoimmune condition. The body’s immune system attacks its own hair follicles as well as other tissues, leading to hair loss. (20)

Androgenetic alopecia is the most common form of hair loss. It’s also known as pattern baldness. It’s caused by an androgen called dihydrotestosterone (DHT) binding to hair follicles in excess. (20) Research has found that both alopecia areata and androgenetic alopecia can be associated with thyroid issues. (3,21) 

Alopecia Areata 

Alopecia areata, an autoimmune condition causing hair loss in circular patches, can be seen in patients with thyroid dysfunction. Patients who suffer from alopecia areata may be more likely to develop a thyroid disease. (21,22) 

Hair loss can be more severe in patients with both conditions. Patients with both conditions may be more likely to see their hair loss progress into a more severe form of alopecia areata that’s known as alopecia universalis. A 2019 systematic review and meta-analysis concluded that patients with alopecia areata had much higher odds of thyroid dysfunction and autoimmune thyroid diseases than the general population. (21,22)

Treatment for thyroid-related hair loss involves addressing the thyroid issue with medication. Treatment for alopecia areata can vary, depending on the severity and the patient’s history. It may involve topical steroids, steroid injections, or minoxidil, a medication that increases blood flow to the scalp to stimulate hair growth. (23) 

Androgenic Alopecia 

Androgenic alopecia is a form of hair loss caused by a hormone known as dihydrotestosterone (DHT) binding to the hair follicles in excess. It’s the most common form of hair loss and can affect both men and women. It’s also known as pattern hair loss or pattern baldness. (20) 

Thyroid conditions and androgenic alopecia can occur at the same time. Research shows that thyroid hormones and androgens interact with each other and can worsen hair loss. (3) 

When the two problems occur together, the pattern of hair loss may be different to the norm. In men, androgenic alopecia starts with hair loss at the temples and progresses across the top of the head. In women, hair typically starts to thin over the crown of the scalp. But both conditions at once can cause hair loss at the temples in women. In both men and women, a thyroid issue can worsen pattern balding and cause people to lose hair at a much quicker rate. (20,24) 

Treatment involves tackling the thyroid issue with medication. Androgenic alopecia is often treated with an oral medication like finasteride, which is a dihydrotestosterone (DHT) blocker, that lowers levels of DHT in the bloodstream. 

Topical treatments including minoxidil may also be offered for pattern hair loss. Minoxidil is an FDA-approved vasodilator that increases blood flow to the scalp, promoting hair growth. Other potential treatments include hair transplant surgery, lifestyle changes, and counseling that can help the patient cope. (24) 

What Does Thyroid Hair Loss Look Like?

A thyroid hair loss pattern can vary greatly. It depends on the type of thyroid condition, along with any other conditions, including other forms of alopecia. Hypothyroidism and telogen effluvium can cause dry, brittle, and dull hair, as well as diffuse hair loss. Hyperthyroidism can cause thinning hair, as well as brittle, greasy hair. (5)

A receding hairline or hair loss at the temples may occur, especially if the patient also has pattern hair loss. It can also cause patches of hair loss if the patient also has alopecia areata. (20,24)

Can Thyroid Hair Loss Be Reversed?

In most cases of thyroid disease, hair loss can be reversed when the thyroid condition is addressed. Conditions causing hypothyroidism can be treated with thyroid replacement therapy. Hyperthyroidism can be treated with anti-thyroid agents, radioactive iodine, beta-blockers, or surgery. If the thyroid issue is caused by a nutritional deficiency, once it’s addressed the issue and hair loss will typically be resolved. (11,13,17) 

If alopecia areata occurs alongside thyroid issues, it can be treated with topical steroids or minoxidil. In most cases, if it’s caught early, hair can regrow. However, if the condition becomes severe, hair follicles can become damaged and hair strands can’t regrow. (23) 

In the case of androgenic alopecia, treatment will involve oral or topical medication. In some cases, hair transplant surgery may be required. With thyroid hair loss, regrowth can take time but in most cases, hair will grow back. (24)