When your thyroid goes awry

Does fatigue drag you down day after day? Do you have brain fog, weight gain, chills or hair loss? Or is the opposite true for you: are you often revved up, sweaty or anxious? Your thyroid gland could be to blame. This great regulator of body and mind sometimes plays up, particularly in women. Getting the right treatment is critical to feel your best and avoid serious health problems.

What is the thyroid gland?

The thyroid is a butterfly-shaped gland in the front of the neck. It produces hormones that control the speed of your metabolism - the system that helps the body use energy. Thyroid disorders can slow down or rev up your metabolism by disrupting the production of thyroid hormones. When hormone levels become too low or too high, you may experience a wide range of symptoms.

Symptom: Weight gain or loss

An unexplained change in weight is one of the most common signs of a thyroid disorder. Weight gain may signal low levels of thyroid hormones, a condition called hypothyroidism. In contrast, if the thyroid produces more hormones than the body needs, you may lose weight unexpectedly. This is known as hyperthyroidism. Hypothyroidism is far more common.

Symptom: Swelling in the neck

A swelling or enlargement in the neck is a visible clue that something may be wrong with the thyroid. A goitre may occur with either hypothyroidism or hyperthyroidism. Sometimes swelling in the neck can result from thyroid cancer or nodules, lumps that grow inside the thyroid. It can also be due to a cause unrelated to the thyroid.

Symptom: Changes in heart rate

Thyroid hormones affect nearly every organ in the body and can influence how quickly the heart beats. People with hypothyroidism may notice their heart rate is slower than usual. Hyperthyroidism may cause the heart to speed up. It can also trigger increased blood pressure and the sensation of a pounding heart, known as heart palpitations.

Symptom: Changes in energy or mood

Thyroid disorders can have a noticeable impact on your energy level and mood. Hypothyroidism tends to make people feel tired, sluggish and depressed. Hyperthyroidism can cause anxiety, problems sleeping, restlessness and irritability.

Symptom: Hair loss

Hair loss is another sign that your thyroid hormones may be out of balance. Both hypothyroidism and hyperthyroidism can cause hair to fall out. In most cases, the hair will grow back once the thyroid disorder is treated.

Symptom: Feeling too cold or hot

Thyroid disorders can disrupt the ability to regulate body temperature. People with hypothyroidism may feel cold more often than usual. Hyperthyroidism tends to have the opposite effect, causing excessive sweating and an aversion to heat.

Other symptoms of hypothyroidism

Hypothyroidism can cause many other symptoms, including:

• Dry skin and brittle nails
• Numbness or tingling in the hands
• Constipation
• Heavy menstrual periods

Other symptoms of hyperthyroidism

Hyperthyroidism can also cause additional symptoms, such as:

• Muscle weakness or trembling hands
• Vision problems
• Diarrhoea
• Irregular menstrual periods

Thyroid disorder or menopause?

Because thyroid disorders can cause changes in your menstrual cycle and mood, the symptoms are sometimes mistaken for menopause. If a thyroid problem is suspected, a simple blood test can determine whether the true culprit is menopause or a thyroid disorder – or a combination of the two.

Who should be tested?

Seek medical advice if you think you may have an overactive or an underactive thyroid. A diagnosis will be based on your symptoms and a blood test, which checks how well your thyroid gland is working.

Hyperthyroidism and hypothyroidism are more common in women than men.

Thyroid neck check

A careful look in the mirror may help you spot an enlarged thyroid that needs medical attention. Tip your head back, take a drink of water, and as you swallow, examine your neck below the Adam's apple and above the collarbone. Look for bulges or protrusions, then repeat the process a few times. Seek medical advice promptly if you see a bulge or lump.

Diagnosing thyroid disorders

If your doctor suspects a thyroid disorder, a blood test called a thyroid function test can help provide an answer. The test measures the level of thyroid stimulating hormone (TSH), a kind of master hormone that regulates the work of the thyroid gland. If TSH is high, it typically means that your thyroid function is too low (hypothyroid). If TSH is low, then it generally means the thyroid is overactive (hyperthyroid). Your doctor may also check levels of other thyroid hormones in your blood. In some cases, imaging studies are used and biopsies are taken to evaluate a thyroid abnormality.

Hashimoto's disease

The most common cause of hypothyroidism is an autoimmune reaction where the body attacks the thyroid gland. The result is damage to the thyroid, preventing it from producing enough hormones. Hashimoto's disease is an example of autoimmune hypothyroidism.

Other causes of hypothyroidism

In some cases, hypothyroidism results from a problem with the pituitary gland, which is at the base of the brain. This gland produces thyroid-stimulating hormone (TSH), which tells the thyroid to do its job. If your pituitary gland does not produce enough TSH, your levels of thyroid hormones will fall. Other causes of hypothyroidism include temporary inflammation of the thyroid or medications that affect thyroid function.

Graves' disease

The most common cause of hyperthyroidism is Graves' disease. This is an autoimmune disorder that attacks the thyroid gland and triggers the release of high levels of thyroid hormones. One of the hallmarks of Graves' disease is the eyes bulging out and appearing more prominent.

Other causes of hyperthyroidism

Hyperthyroidism can also result from thyroid nodules. These are lumps that develop inside the thyroid and sometimes begin producing thyroid hormones. Large lumps may create a noticeable goitre. Smaller lumps can be detected with tests such as ultrasound.

Thyroid disorder complications

When left untreated, hypothyroidism can raise your cholesterol levels and make you more likely to have a stroke or heart attack. In severe cases, very low levels of thyroid hormones can trigger a life threatening drop in body temperature and loss of consciousness. Untreated hyperthyroidism can cause serious heart problems and brittle bones.

Treating hypothyroidism

If you are diagnosed with hypothyroidism, your doctor will probably prescribe thyroid hormones in the form of a tablet. This usually leads to noticeable improvements within a couple of weeks. Long-term treatment can result in more energy, lower cholesterol levels and gradual weight loss. Most people with hypothyroidism will need to take thyroid hormones for the rest of their lives.

Treating hyperthyroidism

The most common treatment for hyperthyroidism is antithyroid medication, which aims to lower the amount of hormones produced by the thyroid. The condition may eventually go away, but many people need to remain on medication for the long term. Other medications may be given to reduce symptoms such as rapid pulse and tremors. Another option is radioactive iodine, which destroys some of the thyroid gland so reducing the amount of thyroid hormone produced. Once part of the gland is destroyed, or removed by surgery, many patients must begin taking thyroid hormones in tablet form.

Surgery for thyroid disorders

Removing the thyroid gland (thyroidectomy) can cure hyperthyroidism, but the procedure is only recommended if antithyroid medications don't work, or if there is a large goitre. Surgery may also be recommended for patients with thyroid nodules. Once the thyroid is removed, most patients require daily supplements of thyroid hormones to avoid developing hypothyroidism. 

What about thyroid cancer?

Thyroid cancer is uncommon, accounting for less than 1% of all cancers in the UK, and is among the least deadly. The main symptom is a lump or swelling in the neck, but fewer than 10% of thyroid nodules turn out to be cancerous. When thyroid cancer is diagnosed, it is often treated with surgery followed by radioactive iodine therapy or external radiotherapy. 

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