The thyroid is a small gland located at the bottom of the neck. It is part of the endocrine system and produces hormones to regulate the body’s metabolism. The two main hormones are called triiodothyronine (T3) and thyroxine (T4).

Thyroid disease refers to disorders causing the thyroid to malfunction and produce an abnormally high (hyperthyroidism) or low (hypothyroidism) amount of hormones. This guide will explore such diseases, highlighting the causes, symptom and prevention / treatments available.

What is thyroid disease?

Thyroid disease refers to medical conditions that prevent the thyroid from producing the right quantity of hormones. This can mean that either too much hormone is being produced (hyperthyroidism) or too little (hypothyroidism). These can be caused by a variety of conditions, some of which run in families.

Hyperthyroidism can result from conditions such as Graves’ disease, thyroiditis, and thyroid nodules. On the other hand, hypothyroidism can result from Hashimoto’s disease, iodine deficiency and absence of the thyroid gland (due to surgical removal).

What are the symptoms of thyroid disease?

Hyperthyroidism causes the body to use energy too quickly and can result in symptoms and signs including:

  • Nervousness
  • Anxiety
  • Irritability
  • Mood swings
  • Weakness
  • Heat sensitivity
  • Difficulty sleeping
  • Persistent tiredness
  • Enlarged thyroid gland (goitre)
  • Fast/irregular heartbeat
  • Twitching or trembling
  • Weight loss
  • Eye problems, such as redness, dryness or vision problems

On the other hand, hypothyroidism can result in symptoms and signs including:

  • Persistent tiredness
  • Cold sensitivity
  • Weight gain
  • Constipation
  • Depression
  • Muscle aches and cramps
  • Weakness
  • Dry skin
  • brittle hair and nails
  • loss of sex drive
  • Carpal tunnel syndrome (pain, numbness and tingling sensation in the hands)
  • irregular/heavy periods
  • Hoarse voice
  • Slow heart rate
  • Thinning or partial loss of eyebrows

If you experience any symptoms or signs you should always talk to your GP. You can find out more about thyroid function tests here.

What are the causes of thyroid disease?

Hyperthyroidism can be caused by the following:

  • Graves’ disease: This is the most frequent cause of hyperthyroidism in the UK, affecting approximately 3 in 4 people with an overactive thyroid. Graves’ disease is an autoimmune disorder where the body’s immune system mistakenly attacks the thyroid, which causes the gland to produce excessive amounts of the hormone responsible for regulating the body’s metabolism. The cause of Graves’ disease is not known but mainly effects young and middle aged women and often runs in families. Stress or smoking may increase the risk of the disease developing.
  • Thyroiditis: This refers to inflammation of the thyroid, which causes it to leak excess hormones, resulting in temporary hyperthyroidism.
  • Thyroid nodules: Thyroid nodules are growths that form inside or on the thyroid. The nodules may be solid or filled with fluid, and whilst they can be cancerous they are usually found to be benign.

Hypothyroidism can be a result of the following:

  • Hashimoto’s disease: This disease causes the body’s immune system to mistakenly attack the thyroid and damage its ability to generate hormones. It is not known what cases Hashimoto’s disease but it does run in families.
  • Removal of the thyroid gland or following radiotherapy to it.
  • Medications: Some drugs including lithium (which is used to treat certain mental health conditions).
  • Iodine deficiency, though this is rare in the UK.

How to prevent and treat vitamin deficiency

There are currently no recognized ways of preventing thyroid disease. However, treatment is available for both hyper and hypothyroidism.

Hyperthyroidism treatment

If you have hyperthyroidism, your GP will guide you to the best treatment for you. The most common treatment options include:

  • Medicines such as thionamides, can be used to treat hyperthyroidism as they work to prevent your thyroid from producing excess hormones. This treatment may be complemented with beta-blockers to alleviate symptoms of hyperthyroidism, and the dosage gradually decreased and stopped once the thyroid is back under control. However, for some, this treatment may need to last in the long term and may sometimes be life-long. People can experience side effects of this treatment in the first few months including fever, headaches, altered taste, itchy rashes, upset stomach and nausea.
  • Radioactive iodine treatment consists of a radiotherapy treatment that destroys cells in the thyroid gland. This consequently leads to a decreased amount of hormone production by the thyroid gland. Reactive Iodine treatment is highly effective and generally only requires one single treatment. This consists of taking a drink or capsule containing iodine followed by a low dose of radiation. It can take a few weeks or sometimes even months for the full treatment effect to take place so medication may be given alongside this treatment initially.
  • Surgery may be required if your thyroid gland is extremely enlarged, if you have severe eye problems caused by hyperthyroidism or if your symptoms return after other treatment options. The surgery is called thyroidectomy, and consists of completely removing the thyroid gland, and medicine will need to be taken for life to make up for the absence of thyroid hormone production.

Hypothyroidism treatment

Hypothyroidism treatment usually simply consists of taking once daily thyroxine replacement tablets (levothyroxine).

Initially you will have frequent blood tests until the correct dosage needed for you is found. Once the correct level has been established, your hormone levels will usually only need to be monitored once per year.

What are considered low or high thyroid hormone levels?

Laboratories use reference ranges to compare blood test analysed by them to what is found normally in healthy people. These ranges differ between laboratories but typical values are:

Hormone Units Recommended range
Thyroid Stimulating Hormone (TSH) mIU/L 0.24-5.54
Free thyroxine (FT4) pmol/l 10-24.5

Levels that are above or below the recommended ranges may indicate a hyperactive or underactive thyroid. Your GP will need to do further tests to establish a diagnosis and recommend the type of treatment needed.

How long does it take to recover from thyroid disease?

This depends on the type of treatment undertaken. Generally, medical treatments for an overactive or underactive thyroid tend to take a few weeks to months to take full effect. The medicines prescribed may need to be taken for anything from a few months to the rest of one’s life. Radioactive treatments can also take a few weeks to a few months to take full effect. As for thyroidectomy (surgical removal of the thyroid), it is recommended to rest for 1-2 weeks and tiredness may be experienced for a while thereafter.

How can I get tested for thyroid disease?

At Home

Your thyroid function can be checked from the comfort of your own home with our Total Home Test Kit, which also includes 33 key readings including a full blood count, key blood markers, immunity readings, as well as thyroid, liver and kidney function. All you need to do is order your kit, take your own sample, send it back in our pre-addressed return envelope, and wait to receive your results online within 8 days.

At a clinic

Alternatively, can opt for our more comprehensive Nutritional Therapy PlanEssential Energy and Fatigue, and Essential Energy and Fatigue Lite plans, as these all include a thyroid function check. These plans consist of in-depth, face-to-face health checks with a Health Assessment Specialists, which you can easily book online at one of over 2,000 mobile clinics available nationwide. You will receive a wide array of other key health markers and a detailed results report sent through the post.