Thyroid and Hair Loss: How Your Hormones Could Be Affecting Your Hair

• December 2, 2025
• Dr Tony Prochazka

Last updated on January 12, 2026

If you’ve noticed more strands falling out when brushing or that your ponytail feels thinner, you’re not alone. While stress, diet, or genetics can all play a role in hair shedding, one of the most overlooked causes is your thyroid.

Your thyroid is a small gland with a big job: it regulates your metabolism, energy and even the growth cycle of your hair. When it’s out of balance, your hair often shows it before the rest of your body catches up.

In this blog, we’ll break down the connection between thyroid and hair loss, explore the signs that your thyroid might be involved and help you understand your options if you’re experiencing hair thinning.

Can Thyroid Conditions Cause Hair Loss?

Yes, both hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid) can lead to hair loss. The thyroid produces hormones (primarily T3 and T4) that play a crucial role in regulating the growth cycle of hair follicles.

When these hormone levels become too high or too low, the hair cycle can shift into a prolonged resting phase (telogen), leading to diffuse thinning and increased shedding.
This is why one of the first signs of a thyroid imbalance in many people is unexpected hair changes, long before other symptoms show up.

Symptoms of thyroid hair loss may include dry or brittle hair, more hair falling out than usual and a more visible scalp.

What Does Thyroid Hair Loss Look Like?

Thyroid-related hair loss is usually diffuse, meaning it affects the entire scalp rather than forming distinct bald patches. This even thinning gives hair a less dense appearance overall and can make the scalp more visible through your hair.

More Hair Falling Out Than Usual

You might start noticing extra strands collecting in your hairbrush, on your pillow, or in the shower drain. This gradual shedding often becomes more noticeable over time rather than happening all at once.

Thinner Ponytail or Visible Scalp

Many people first realise something has changed when their ponytail feels smaller, or their scalp becomes more visible when styling or parting their hair. This type of thinning is one of the earliest signs of thyroid-related hair loss.

Dry or Brittle Hair

Hair texture can also change. Strands may feel coarse, dull, or prone to breakage. This happens because thyroid hormone imbalances can reduce the amount of sebum produced by your scalp, leading to dryness and fragility.

Thinning of the Eyebrows

One classic sign of hypothyroidism is thinning of the outer third of the eyebrows. This subtle change can develop gradually and is often overlooked until other symptoms appear.

Unlike genetic hair loss, which typically begins with a receding hairline or balding in specific areas, thyroid hair loss tends to occur evenly across the scalp. In some cases, body hair, eyebrows and eyelashes may also be affected.

Other Symptoms That Might Point to a Thyroid Issue

If you’re experiencing hair loss and any of the following symptoms, it may be worth getting your thyroid tested:

• Constant fatigue, sluggishness, or low energy
• Unexplained weight gain or loss
• Feeling unusually cold or overheated
• Irregular menstrual cycles or fertility issues
• Depression, anxiety, or brain fog
• Brittle nails or very dry skin

A simple blood test can check your TSH, T3 and T4 hormone levels. From there, your GP or an endocrinologist can help determine if your thyroid is the root cause.

Hair loss from a thyroid condition may be able to be reversed, depending on how early the condition is diagnosed and treated.

Can Hair Loss From Thyroid Be Reversed?

In many cases, yes, but it depends on how early the condition is diagnosed and treated. Once thyroid hormone levels are stabilised through medication or other medical interventions, hair follicles often return to their normal growth cycle. However, this process takes time.

You may not see visible regrowth for 3 to 6 months, and full regrowth can take longer, depending on the severity and how long the thyroid was imbalanced.

Supportive treatments such as topical minoxidil, low-level laser therapy and hair-focused nutritional supplements may help stimulate dormant follicles and encourage regrowth during recovery.

How to Support Hair Health While Managing Thyroid Issues

Here are ways to give your hair a better chance of bouncing back, especially while your thyroid levels are being corrected.

Be gentle with your hair
Avoid excessive heat styling, tight hairstyles, or harsh brushing. Protecting fragile, regrowing hair helps reduce breakage.

Nourish your body
A diet rich in protein, zinc, selenium, biotin and iron supports healthy follicle function. As thyroid disorders may interfere with your body’s ability to absorb or maintain these nutrients, you may want to speak with your doctor to determine whether additional supplementation is appropriate.

Manage stress
Chronic stress can worsen thyroid and hair loss symptoms. Mindfulness or exercise may help restore balance.

How Crown Clinic Can Help

If your thyroid is under control but your hair isn’t showing signs of improvement, or if you’re seeing bald spots or sudden patchy hair loss, it may be time to speak to a hair loss specialist. Here’s how The Crown Clinic can help:

FUE (Follicular Unit Extraction)

This popular hair restoration method involves extracting individual follicles from a donor area, usually the back of the scalp and reimplanting them in thinning zones. It’s minimally invasive, leaves virtually no visible scarring and delivers natural regrowth results over time.

Sapphire Hair Transplant

A refined evolution of FUE, this approach uses sapphire blades to create finer, more precise incisions. The result is denser graft placement, faster healing and even smoother, natural-looking outcomes, particularly effective for restoring the frontal hairline.

Non-Surgical Treatments

For those who prefer a non-invasive approach, we offer clinically proven therapies including prescription topical solutions and medical-grade supplements. These treatments focus on stimulating dormant follicles, reducing inflammation and promoting scalp balance for healthier hair.

STIM Medical Hair Care

To support overall hair health we recommend STIM shampoos, conditioners, and topical treatments. These products contain active ingredients that promote hair follicle stimulation, improve scalp health, and strengthen hair. Formulated with ingredients like biotin, caffeine, and peptides, With regular use, STIM products can revitalize hair growth and reduce hair shedding. For more information visit www.stimhair.com

Each treatment plan begins with a free consultation to assess your scalp, identify the underlying cause of your hair loss and design a personalised plan to support optimal regrowth.

Book a Free Hair Consultation

Concerned about hair loss? Our experts are here to help.

At Crown Clinic, we bring over 50 years of experience in hair restoration and offer a truly personalised approach to treatment. Our expert team can offer personalised options to encourage healthy regrowth.

📞 Call us on +61 2 9134 4788 or book your free consultation here to get started.

FAQs

How do I know if my thyroid is causing hair loss?

Thyroid-related hair loss is usually diffuse (spread out across the scalp), not patchy or localised. If it’s accompanied by fatigue, mood changes, weight fluctuations, or cold sensitivity, your thyroid could be involved. A blood test checking TSH, T3 and T4 levels is the most accurate way to find out.

Can hair loss from thyroid conditions grow back?

Yes, in most cases. Once your thyroid hormone levels are balanced through medication, hair follicles may return to their normal growth cycle. It can take several months to see improvement, and some individuals may benefit from additional hair support therapies during recovery.

How can I stop my thyroid condition from making me lose hair?

The first step is managing your thyroid condition under medical supervision. In addition, supporting your body with a nutritious diet, a gentle hair care routine, and potentially topical treatments can all help protect and encourage regrowth.

What thyroid conditions cause hair loss?

Both hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid) can trigger hair shedding. Autoimmune thyroid conditions like Hashimoto’s or Graves’ disease are also linked to chronic hair loss.