Thyroid Conditions and Hair Loss: What You Need to Know

Is your hair starting to look thinner than usual? It’s common for men to experience some degree of hair loss at some point in our lives. In fact, one form of hair loss called androgenetic alopecia (or male pattern baldness) is thought to affect 50 million men in the United States alone

While androgenetic alopecia is the most common type of hair loss men experience, hair loss can also occur as a result of certain medical conditions. 

If you have a thyroid condition such as hypothyroidism or hyperthyroidism, it’s possible that this could contribute to hair loss. Thyroid conditions can also occur in conjunction with autoimmune diseases such as alopecia areata, which can affect the growth of your hair. 

Hair loss from thyroid conditions can vary in severity, from mild diffuse thinning to almost total loss of hair on your scalp. Below, we’ve explained why and how thyroid-related hair loss occurs, as well as what you can do to treat hair loss that’s caused by a thyroid condition. 

The Basics of Hair Loss

Hair loss can occur for a large variety of reasons. In men, the most common cause of hair loss is male pattern baldness — a form of hormonal hair loss that’s caused by a genetic sensitivity to the hormone dihydrotestosterone, or DHT.

This type of hair loss occurs when DHT gradually miniaturizes the hair follicles, stopping them from producing new hairs.

However, it’s also possible for your thyroid to contribute to hair loss by disrupting your body’s natural hair growth cycle.

As we’ve covered in our guide to the hair growth process, every single hair on your scalp goes through a four-stage growth process, with each stage corresponding to a different phase in the hair’s development:

  • During the anagen phase, the hair grows from the follicle
  • During the catagen phase, the follicle shrinks and the hair detaches from your scalp
  • During the telogen phase, a new hair starts to grow underneath the old hair
  • During the exogen phase, the old hair falls out and is replaced by the new hair

As part of this process, old hairs that have reached the end of their growth cycle are constantly falling out from your scalp, causing you to lose about 50 to 100 hairs every day. Since your hair follicles don’t all grow in sync, this daily loss doesn’t have any impact on your appearance. 

Understanding this simple process is key to understanding how thyroid disorders, as well as a range of other medical conditions, can affect your hair.

Hair Loss and Your Thyroid

Thyroid conditions such as hypothyroidism and hyperthyroidism can cause a diverse range of symptoms, from reduced or increased energy levels to changes in your body composition and weight. It’s also possible for these conditions to affect your hair. 

Because your thyroid plays a vital role in regulating so many bodily functions, any disruption to the production of thyroid hormones such as triiodothyronine (T3) and thyroxine (T4) can affect numerous important bodily processes. 

This includes the healthy growth of your hair. If your thyroid function is impaired, your hair might not grow as quickly as it normally would. This means that as old hairs reach the end of their hair growth cycle, they aren’t adequately replaced by new ones. 

Symptoms of Thyroid-Related Hair Loss

Unlike male pattern baldness, which usually causes your hair to fall out in a clear, recognizable pattern, hair loss caused by a thyroid condition looks a little different. Instead of a balding crown or receding hairline, you’ll normally notice diffuse thinning across your entire scalp.

In simple terms, all of your hair might start to look a little thinner than usual, letting you see your scalp quite easily in bright light. 

Certain thyroid conditions can also change the texture of your hair. If you have hyperthyroidism (an overactive thyroid), your hair might feel overly fine and brittle. If you have hypothyroidism (an underactive thyroid), your hair might feel dry, harsh and more coarse than normal.

Diagnosing Thyroid-Related Hair Loss

Thyroid conditions such as hypothyroidism and hyperthyroidism don’t only affect the hair -- they can also result in a range of other symptoms.

If you have hypothyroidism (an underactive thyroid), your symptoms may include:

  • Fatigue and tiredness
  • Weight gain
  • Dry skin
  • Slow heart rate
  • Increased sensitivity to cold
  • Discomfort, pain and/or swelling of the joints
  • Muscular weakness and muscle aches, stiffness and pain
  • Hoarse voice
  • Constipation
  • Impaired memory
  • Depression
  • High cholesterol levels

If you have hyperthyroidism (an overactive thyroid), your symptoms may include:

  • Rapid and/or irregular heartbeat or heart palpitations
  • Weight loss and difficulty maintaining a healthy weight
  • Increased appetite, often without an increase in body weight
  • Anxiety, irritability, nervousness and physical tremors
  • Increased sensitivity to heat
  • Sweating
  • Muscle weakness and/or fatigue
  • More frequent bowel movements
  • Insomnia or difficulty falling asleep

It’s also worth noting that in people over the age of 60, hyperthyroidism is sometimes mistaken for depression. Older adults may exhibit different symptoms — like loss of appetite or withdrawing from people. 

Thyroid conditions such as hypothyroidism and hyperthyroidism are quite easy to diagnose. If you display symptoms of a thyroid condition, your healthcare provider might request for you to take a blood test to measure your levels of thyroid-stimulating hormone (TSH) and thyroxine (T4).

If these levels are unusual, your healthcare provider may recommend additional testing to identify the root cause of your thyroid condition. 

If you’re worried that you might have thyroid-related hair loss, the best approach is to talk with your healthcare provider doctor about your symptoms. 

How to Treat Thyroid-Related Hair Loss

If your healthcare provider diagnoses you with a thyroid condition, you’ll likely be prescribed medication to treat your condition. 

For hypothyroidism, your healthcare provider may prescribe a synthetic thyroid hormone such as Levo-T® or Synthroid®. These medications work by bringing your thyroid hormones up to a normal level.

For hyperthyroidism, your healthcare provider may prescribe an anti-thyroid medication such as Tapazole® (methimazole) or propylthiouracil. These medications stop your thyroid gland from producing overly high levels of thyroid hormones. 

Depending on your symptoms, treatment for hyperthyroidism may include radioactive iodine and/or beta blockers. Severe cases of hyperthyroidism are occasionally treated by removing some or all of the thyroid gland in a procedure known as thyroidectomy. 

Most of the time, thyroid-related hair loss resolves on its own after you successfully treat the underlying condition. After treating your thyroid condition, it can take several months for your hair to start growing again.

You might be able to speed up this growth using minoxidil, a topical medication that improves blood flow to the scalp. Because thyroid-related hair loss isn’t caused by DHT, finasteride isn’t effective at treating or preventing this form of hair loss. 

Thyroid Conditions and Alopecia Areata

Many people with thyroid conditions such as hypothyroidism and hyperthyroidism suffer from autoimmune thyroid disease. People affected by autoimmune thyroid disease have a greater risk of developing other autoimmune conditions, such as alopecia areata.Alopecia areata is a type of autoimmune hair loss in which the body’s immune system targets and damages the hair follicles. Hair follicles that are targeted by the immune system can stop producing new hairs, resulting in hair loss. 

Hair loss from alopecia areata usually occurs in small, often circular patches, rather than the receding hairline or crown hair loss of male pattern baldness or the diffuse thinning of thyroid hair loss. Some people with alopecia areata develop bands of bald skin, called ophiasis.

In severe cases, alopecia areata can also cause total hair loss on the scalp, as well as loss of hair in the eyebrows, eyelashes and beard area. Some  people with alopecia areata may notice that their nails become slightly red, with a weak, rough and brittle texture or may have pitting in their nails. 

If you have a thyroid condition and believe you’re suffering from alopecia areata, contact your healthcare provider.. Several effective treatments can help you to manage the symptoms of alopecia areata, including corticosteroids. 

Medications that stimulate hair growth, such as minoxidil, may also help to promote hair growth in people with alopecia areata.  

In Conclusion

If you have a thyroid condition, it’s possible that it could cause some degree of hair loss. Unlike male pattern baldness, thyroid-related hair loss usually doesn’t result in a receding hairline or a bald spot at the crown — instead, it usually leads to diffuse hair loss across the entire scalp. 

Most cases of thyroid-related hair loss get better on their own after treating the specific thyroid condition responsible for the hair loss. Medications such as minoxidil may  help to promote the growth of new, healthy hair. 

If you’re concerned about thyroid-related hair loss, contact your healthcare provider.. With the right treatment for your thyroid condition, you can manage your symptoms and regrow any lost hair.

Learn More About Treating Hair Loss

Worried you’re starting to lose your hair? You’re not alone. Hair loss is a common issue that affects men of all ages and backgrounds. Our guide to hair growth products covers how the latest, most popular treatment options work, with real, scientific data on their effectiveness. 

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.