Thyroid problems: how to recognize an underactive or overactive thyroid

What does the thyroid do and where is it located?

Your thyroid is a small organ in your neck, at the front of your neck, below your Adam's apple. It is shaped like a butterfly.

The thyroid produces hormones that help your body extract energy from your food. This is called metabolism. Thyroid hormones thus determine how fast many processes in your body proceed, such as your heart rate, body temperature, and digestion.

The amount of hormone your thyroid produces is regulated by the pituitary gland: a small gland located beneath your brain. The pituitary gland produces TSH, a hormone that signals the thyroid to get to work. If there is too little thyroid hormone in your blood, the pituitary gland produces more TSH. If there is too much, it produces less TSH.

Symptoms of an underactive thyroid

With an underactive thyroid, too few thyroid hormones enter your bloodstream. Your body then produces less energy, and everything slows down. You might notice this, for example:

• you get cold easily;
• you gain weight;
• you feel tired or sluggish;
• you have difficulty having a bowel movement;
• your hair is dry, or you are losing more hair;
• your skin is dry.

These symptoms usually develop gradually. As a result, you often only notice that something has changed after months.

A slow thyroid is usually caused by Hashimoto's disease. With this disease, your immune system attacks your own thyroid, causing it to produce less and less hormone. Other causes include inflammation of the thyroid after childbirth, surgery or radiation of the neck, treatment with radioactive iodine, certain medications (such as amiodarone and lithium), and products high in iodine, such as seaweed or kelp tablets.

Symptoms of an overactive thyroid

With an overactive thyroid, there are actually too many thyroid hormones in your blood. Your body then starts working faster. You might notice this, for example:

• you lose weight, even though you eat well;
• you feel restless, anxious, or easily irritated;
• your heart beats faster;
• you sweat a lot;
• you sleep poorly;
• you tremble;
• you have diarrhea;
• your neck thickens because your thyroid gland enlarges;
• you have eye problems.

Usually, an overactive thyroid is caused by Graves' disease. That is also a disease in which your immune system attacks your thyroid, but in this case, the thyroid actually produces too much hormone. Other causes include a benign tumor in the thyroid, inflammation of the thyroid caused by a virus, and substances containing iodine, such as certain medications and contrast agents.

Early thyroid symptoms: why are they difficult to recognize?

According to the guidelines for general practitioners, the symptoms of thyroid problems are usually not specific. Being tired, gaining weight, sleeping poorly, feeling restless, or hair loss can all be caused by a thyroid problem, but much more often they have another cause. Think of stress, lack of sleep, menopause, an infection, or iron deficiency.

Therefore, symptoms say little about your thyroid as long as no blood test has been performed. The reverse is also true: someone who has been mildly fatigued for years does not automatically have a thyroid problem. Only a blood test can show whether your thyroid is underactive or overactive.

Lump in your throat or a swollen neck: is that caused by your thyroid?

A swollen neck. An enlarged or swollen thyroid can be visible or palpable as a swelling at the front of your neck. This is called a goiter. It can occur with an overactive or underactive thyroid, but also with a thyroid that functions normally. You should always have a swelling in your neck assessed by your GP.

A lump in your throat. The sensation that there is something in your throat, even though there isn't, is called a globus sensation. This is usually not caused by the thyroid, but by factors such as stress, tense throat muscles, a dry or irritated throat, or heartburn. It usually goes away on its own within a few weeks.

Ribs in your nails. Longitudinal ridges in your nails are common and are seen more often as you get older. They are not a reliable sign of a thyroid problem.

Thyroid complaints in women

Thyroid problems occur much more frequently in women than in men. An underactive thyroid is more than four times as common in women. Both thyroid problems occur more frequently as you get older.

In women, a few life stages play a role:

• Before pregnancy: do you want to become pregnant and do you have thyroid problems? Then contact your GP.
• After childbirth the thyroid can become temporarily inflamed. As a result, it can first work too fast and then too slow. This often resolves on its own.
• During pregnancy a well-functioning thyroid is important for you and your baby. If you know you have a thyroid problem and you are pregnant, tell your GP immediately.
• Around menopause symptoms such as fatigue, poor sleep, mood swings, and hot flashes sometimes resemble thyroid complaints. Blood tests can help differentiate.

How is a thyroid problem diagnosed?

A thyroid problem is diagnosed with a blood test. The doctor looks at two values:

• TSH, the hormone from the pituitary gland that controls the thyroid;
• free T4, the most important thyroid hormone in your blood.

With an underactive thyroid, the TSH value is too high and the free T4 value is too low. With an overactive thyroid, it is the other way around: the TSH value is too low and the free T4 value is too high.

Thyroid values ​​on the borderline. Sometimes only the TSH value is slightly elevated, while free T4 is normal. With a slightly elevated TSH and a normal free T4, treatment with thyroid hormone is usually not necessary. The TSH often returns to normal on its own. If you experience symptoms consistent with an underactive thyroid, or if you are pregnant, please contact your GP again.

What if a thyroid problem is not treated?

An underactive thyroid that is not treated usually does not go away on its own. The symptoms persist and may gradually worsen. An underactive thyroid can usually be effectively treated with medication containing thyroid hormone. You take this medication every day, often for the rest of your life, and your blood is checked regularly.

An overactive thyroid is taxing on your body, especially your heart: among other things, it increases the risk of atrial fibrillation, a form of irregular heartbeat. Therefore, the GP will refer you to a specialist at the hospital for further examination and treatment. If you smoke and have Graves' disease, quitting smoking is especially important, as smoking increases the risk of eye problems.

Get your thyroid tested

Do you want to know what your thyroid values ​​are? TSH is measured in every Zample blood test kit, starting with the Essential Blood Test. In addition, free T4 is measured in the Men Premium Blood Test and the Women Premium Blood Test.

An abnormal TSH value is an indication, not a diagnosis. To determine whether your thyroid is underactive or overactive, free T4 is also required, and sometimes a repeat of the test. Always discuss an abnormal result with your GP, especially if you also have symptoms.

When to see the GP?

Make an appointment with your GP if:

• you have symptoms consistent with an underactive or overactive thyroid;
• you are pregnant or planning to become pregnant and have a thyroid problem.

Call your GP or the out-of-hours GP service immediately if your heart continues to beat very fast, or if you are breathing rapidly or with difficulty.

Conclusion

Your thyroid regulates how fast your body works. If it works too slowly, you may feel tired, cold, and gain weight. If it works too fast, you may lose weight, be restless, and have a rapid heartbeat. However, these symptoms are not specific: they often have a different cause.

Only a blood test, using TSH and free T4, can show whether your thyroid is functioning properly. A slightly abnormal value without symptoms does not need to be treated. If you have symptoms that do not go away, a swelling in your neck, or eye problems, see your GP.