THYROID ACTIVITY CAN CORRELATE WITH THE CONDITION OF YOUR HAIR. HERE, WE EXPLORE THE LINK.
We all know the common external factors that impact hair health: from regular bleaching treatments to overzealous straightening sessions, there are plenty of habits we know to keep in check.
But internal factors can also affect hair health, and these issues often fly under the radar, going undetected for a long time. One such example is your thyroid, and how imbalances in its function can influence the strength and resilience of your strands.
Your thyroid gland takes iodine from the food you eat and uses it to make hormones. These hormones help regulate your metabolism, influencing weight, energy levels, body temperature, and the health of your skin, hair, and nails.
Thyroid dysfunction can occur when the gland produces too little or too much of two hormones: triiodothyronine (T3) and thyroxine (T4).
An underactive thyroid, medically known as hypothyroidism, slows your metabolism and can cause fatigue, weight gain and low mood. At the other end of the spectrum, an overactive thyroid (hyperthyroidism) sends your system into overdrive. Common symptoms include weight loss, a rapid or irregular heartbeat, restless sleep and anxiety.
So, what does this have to do with your hair?
Each strand grows from a follicle beneath the skin’s surface, where tiny blood vessels supply the oxygen and nutrients needed for growth. Thyroid hormones help regulate this process, so an imbalance can affect both how your hair grows and how it feels.
An underactive thyroid can leave strands dry, brittle, and more prone to breakage, while an overactive thyroid may increase shedding. When either condition is severe or prolonged, you may notice thinning across the scalp.
The scalp can feel the effects too. With an underactive thyroid, slower skin renewal and reduced oil and sweat gland activity can contribute to dryness, flaking and irritation.
Thyroid health and hair loss can also have an autoimmune dimension. Alopecia areata can occur alongside thyroid dysfunction, with a recognised association with autoimmune thyroid conditions such as Graves’ disease and Hashimoto’s thyroiditis.
Other hormonal imbalances can also affect hair growth too. Polycystic ovary syndrome (PCOS), which can occur alongside thyroid dysfunction, may contribute to thinning.
During pregnancy, hormonal shifts often make hair thicker, although thyroid dysfunction can still cause shedding or brittleness. If you notice changes that concern you, speak to your GP or midwife.
Finding the right support
Changes to your hair can feel unsettling, especially when you’re unsure what’s behind them. Your GP can arrange thyroid function blood tests where appropriate, check for other causes and recommend treatment. A trichologist can offer additional support with scalp health, fragile strands and a hair care routine suited to your needs.
With successful thyroid treatment, regrowth is often possible, though it can take several months. Giving your hair time to recover and yourself a little patience is part of the process.
6 ways to support your hair and scalp
Nourish yourself well. Choose a varied diet with plenty of vegetables, fruit, protein, whole grains and healthy fats, and keep hydrated. Simple, sustainable habits are enough.
Be thoughtful about supplements. Ask your GP whether you need them before taking iron, biotin or other hair supplements. They may help with a confirmed deficiency, but excess amounts can be harmful. Biotin can also affect thyroid blood test results, so discuss it to your clinician.
Turn down the heat. Give your hair regular breaks from styling tools. When you do use them, choose a lower temperature and apply a heat protectant.
Keep conditioning gentle. Use a conditioner or moisturising mask suited to your hair, and seek advice if scalp dryness or irritation persists.
Loosen up. Detangle gently and opt for comfortable hairstyles that avoid pulling at the roots.
Be kind to yourself. Hair changes can take an emotional toll. Make space to rest and reach out for support when you need it.
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