Hypothyroidism is a condition that occurs when the thyroid gland doesn’t produce enough hormones. Due to their role in metabolism, having low levels of these hormones can cause symptoms like fatigue and weight gain – and, if left untreated, increase the risk of more serious health issues.
According to statistics, hypothyroidism affects 2% of the UK population – including over 5% of those over 60. It’s also significantly more common in women than men, as a result of factors such as menopause, which impact hormone levels.
Due to its emotionally taxing symptoms and difficulty to diagnose, hypothyroidism can be challenging to live with. However, the good news is that, with the right treatment, most people are able to live normal, healthy lives.
Here, we’ll take a closer look at hypothyroidism – including symptoms, causes, treatment, and lifestyle tips.
What is hypothyroidism?
The thyroid is a small, butterfly-shaped gland that sits at the front lower part of your neck, in front of your windpipe.
There are three main hormones that the thyroid gland releases into the bloodstream: thyroxine (T4), triiodothyronine (T3), and calcitonin. T3 and T4 play a key role in metabolism (how your body regulates and uses energy), with T4 being the primary thyroid hormone produced by the thyroid gland. T4 is converted to T3 in order for the body to use it. Collectively, T3 and T4 are referred to as ‘thyroid hormone’.
Hypothyroidism – also called underactive thyroid disease – occurs when the thyroid gland doesn’t produce enough thyroid hormone. Because metabolism affects everything from body temperature regulation and heart rhythm to weight management, hypothyroidism can significantly impact health by slowing these processes down.
There are two types of hypothyroidism: primary and secondary. Primary hypothyroidism is caused by issues with the thyroid gland itself, while secondary hypothyroidism is the result of another problem or health condition that interferes with the thyroid’s hormone-producing ability. Treatment for primary and secondary hypothyroidism is the same.
Hyperthyroidism, where the thyroid gland produces too much thyroid hormone, is the opposite of hypothyroidism. You can find out more about hyperthyroidism on the NHS website.
What are the symptoms of hypothyroidism?
Symptoms of hypothyroidism can often be subtle, develop slowly, and reflect those of other health conditions. This means the condition can easily be missed or misdiagnosed. In fact, many people don’t realise they have hypothyroidism for several years.
According to the NHS, common symptoms of hypothyroidism include…
- Tiredness
- Being sensitive to the cold
- Unexplained weight gain
- Anxiety and depression
- Constipation
- Achy or weak muscles
- Muscle cramps
- Loss of libido
- Brittle hair and nails
- Dry, scaly skin
- Pain, numbness, or a tingling sensation in fingers or hands (carpal tunnel syndrome)
- Irregular or heavy periods
Research also suggests that hypothyroidism can make elderly people more prone to developing depression and memory problems.
If you’re experiencing any of these symptoms, it’s important to speak to your GP. If left untreated, hypothyroidism can increase your risk of more serious health conditions, including goitre (an enlargement of the thyroid gland), heart issues, and peripheral neuropathy.
Low levels of thyroid hormones can also begin to affect how the body processes fat – which can lead to high cholesterol, atherosclerosis (clogging of the arteries), and an increased risk of serious heart conditions, such as angina and heart attack.
According to the NHS, later, more serious symptoms of hypothyroidism can include a slow heart rate, puffiness in the face, anaemia, and a low-pitched, hoarse voice.
What can cause hypothyroidism and are there any risk factors?
According to the NHS, most cases of hypothyroidism are caused by previous thyroid treatment or autoimmune conditions that cause the immune system to attack the thyroid gland.
While hypothyroidism can affect anyone, there are certain factors – including age, gender, and family history – that can increase your risk. We’ll cover these below.
Autoimmune disorders
Hypothyroidism often occurs when the immune system, responsible for protecting the body from infection, attacks the thyroid gland – affecting its ability to produce enough thyroid hormone.
Hashimoto’s disease is the most common type of autoimmune condition that causes hypothyroidism. Health experts are currently unsure what causes Hashimoto’s disease, but it’s known to run in families. Other autoimmune disorders, such as rheumatoid arthritis, lupus, and type 1 diabetes, can also increase your risk.
Previous thyroid treatment
In some cases, hypothyroidism can occur as a side effect or complication of previous thyroid gland treatment.
Examples include surgery or treatment called radioactive iodine therapy, sometimes used for hyperthyroidism (overactive thyroid) or thyroid cancer.
Less common causes of hypothyroidism
According to the NHS, some less common causes of hypothyroidism include…
Iodine deficiency
One of the most common causes of hypothyroidism worldwide is iodine deficiency. However, iodine deficiency is rare in the UK.
Pituitary gland issues
Located at the base of the brain, the pituitary gland is responsible for regulating thyroid function by producing thyroid-stimulating hormone (TSH). As a result, damage to the pituitary gland can increase the risk of hypothyroidism.
Congenital hypothyroidism
Babies are sometimes born with an underactive thyroid gland because the thyroid gland doesn’t develop properly in the womb. This is called congenital hypothyroidism.
According to the NHS, congenital hypothyroidism is rare and usually picked up during routine screenings after birth. Great Ormond Street Hospital for Children has more information on congenital hypothyroidism.
Certain infections and medications
Experts have linked certain viral infections and medications with a greater risk of hypothyroidism. Examples include…
- Lithium – a medication sometimes used to treat certain mental health conditions, including depression and bipolar disorder
- Interferons – a type of medication sometimes used to treat certain types of cancer and hepatitis C
- Amiodarone – a medicine sometimes used to treat arrhythmia (irregular heartbeat)
If you’re concerned that a medication you’re taking may be affecting your thyroid function, it’s important to speak to your GP.
Other risk factors for hypothyroidism
Several factors, including age, gender, and family history, can increase your risk of developing hypothyroidism.
For example, the condition is significantly more common in women than men, particularly those over 60 – affecting 15 in every 1,000 women compared to one in every 1,000 men in the UK. This is due to factors such as menopause, which causes hormone levels to fluctuate.
How is hypothyroidism diagnosed?
If you suspect you may have hypothyroidism, it’s important to make an appointment with your GP. They’ll speak to you about your symptoms and, if necessary, carry out a thyroid function test.
A thyroid function test is a blood test used to measure levels of T4 (and sometimes T3) and thyroid-stimulating hormone (TSH) in the blood. It’s the only accurate way to detect hypothyroidism.
Having high levels of TSH and low levels of T4 may signal that you have an underactive thyroid. You’ll be able to discuss treatment options with your GP.
If your test results show raised TSH but normal T4 levels, this imbalance may mean you’re at risk of developing hypothyroidism in the future. In this case, your GP may recommend that you have repeat blood tests every so often to monitor your hormone levels.
The reason that blood testing to check T3 levels is less common is because T3 levels can often remain normal, even if you have hypothyroidism – and is usually the last hormone, after T4 and TSH, to show abnormal readings. Head over to the Lab Tests Online UK website for more information on different types of thyroid function tests.
How is hypothyroidism treated?
Hypothyroidism is usually treated by taking daily hormone replacement tablets called levothyroxine. Levothyroxine replaces the primary thyroid hormone, T4, which your thyroid doesn’t produce enough of.
You’ll need to have regular blood tests to determine the correct dose of levothyroxine. According to the NHS, this can take a little while to get right. Your GP may initially prescribe you a low dose of levothyroxine and increase it gradually, depending on how your body responds.
It’s important to note that everyone is different and, while some people start to feel better soon after beginning treatment, others may not notice improvements for several months. Once you’ve found the correct dose, you’ll typically have an annual blood test to monitor your hormone levels.
If blood tests suggest you may have an underactive thyroid but you’re not experiencing symptoms or they’re very mild, you may not need treatment. In these cases, your GP will usually monitor your hormone levels every few months and prescribe levothyroxine later if symptoms develop.
For more information on treatment for hypothyroidism, including potential side effects of levothyroxine, head over to the NHS website. Luckily, when treated properly, hypothyroidism complications are rare.
Can diet changes help to manage hypothyroidism?
If you’ve been diagnosed with a thyroid condition like hypothyroidism, it’s natural to want to look for ways to help manage your symptoms.
Research is currently ongoing into the potential effects of effects of certain supplements on hypothyroidism. For example, in this study, taking ginger supplements was found to help relieve symptoms of hypothyroidism; and the results of this study suggest that zinc, whether alone or combined with other supplements, may improve outcomes in people with hypothyroidism. Other studies have linked vitamin B12 and magnesium deficiencies with a greater risk of hypothyroidism.
However, further research is needed to confirm these findings. And, it’s important to note that, while many websites offer advice on what you should or shouldn’t eat if you have a thyroid condition, there are currently no specific food or supplement rules formally recommended by experts.
Instead, the best thing you can do is focus on eating a healthy, balanced diet to provide your body with all of the essential nutrients it needs. Among other things, this involves eating plenty of fruit and vegetables, increasing your intake of fibre, avoiding processed foods, staying hydrated, and reducing your intake of added sugar.
You can find out more about current research into supplements for hypothyroidism on the British Thyroid Foundation website.
I’m struggling with hypothyroidism – what support is available?
If you’re currently struggling with the symptoms of hypothyroidism, it’s important to remember that you’re not alone. There are various resources available and ready to help support you.
For example, Thyroid UK provides information and support for people with thyroid disorders in the UK. This includes webinars and online community events where you can connect with others going through similar experiences. Similarly, the British Thyroid Foundation offers telephone support, patient forums, as well as valuable research into how to help people live better with thyroid disease.
Final thoughts…
Due to its role in metabolism, living with a thyroid condition like hypothyroidism can impact everything from energy levels to weight management. However, the good news is that, with the right treatment, hypothyroidism is a manageable condition.
For further reading, head over to our general health section. Here, you’ll find information on everything from important health checks to bone, joint, and muscle health.
Do you have any experience with hypothyroidism that you’d like to share? We’d be interested to hear from you in the comments below.
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