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Hypothyroidism 101: Symptoms, causes and treatment of underactive thyroid

Hypothyroidism 101: Symptoms, causes and treatment of underactive thyroid
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Experts estimate that around 5 to 10 per cent of Singapore’s population experience thyroid issues. With symptoms that can take years to become apparent, hypothyroidism is a thyroid disorder that we should be on the lookout for.

What is Hypothyroidism?

Hypothyroidism refers to when you have an underactive thyroid. The thyroid is a small, butterfly-shaped endocrine gland in the front of your throat, located under your Adam’s apple and secretes thyroxine and triiodothyronine, hormones that help regulate your metabolic, cardiovascular, and developmental processes.

In hypothyroidism, your thyroid ceases to produce enough of these crucial hormones for your body, leading to impairment of your bodily processes.

Hyperthyroidism vs Hypothyroidism

Hyperthyroidism is often contrasted with hypothyroidism, given that they refer to opposing thyroid disorders. While hypothyroidism refers to an underactive thyroid , hyperthyroidism refers to an overactive thyroid . In hyperthyroidism, your thyroid produces too much of a hormone called thyroxine. The overproduction of the hormone supercharges your metabolism and can cause unintended weight loss and a rapid or irregular heartbeat.

Hypothyroidism symptoms: Signs of an underactive thyroid

Depending on how severe your hormone deficiency is, or how underactive your thyroid is, the symptoms of hypothyroidism can vary. The problems, however, typically develop slowly over a number of years.

Symptoms may be easy to miss at first, as they don’t register as urgent medical issues, and are non-specific to hypothyroidism. Initially, you may in fact, dismiss them as signs of aging. Over time, however, you’re likely to notice more obvious symptoms that cannot be waved away with the sleight of your hand.

You should be wary of hypothyroidism if you display the following signs and symptoms:

  • Unexplained fatigue, or tiredness
  • Heightened sensitivity to cold temperatures
  • Constipation
  • Dry skin
  • Unplanned weight gain
  • Facial swelling, or a puffy face
  • Hoarseness, or a raspy, strained and breathy voice
  • Weakness in your muscles
  • High blood cholesterol level
  • Muscle aches, tenderness and stiffness
  • Pain, stiffness or swelling in your joints
  • Heavier than normal or irregular menstrual periods
  • Thinning hair
  • Slowed heart rate
  • Depression
  • Impaired memory
  • Goiter, or an enlarged thyroid

As symptoms are non-obvious and can be non-specific, it is important to seek medical advice or consult a doctor as soon as possible if you suspect that you have hypothyroidism. It is always best to set our minds at ease and reassure our loved ones as well, when it comes to our health.

If you’d like to arrange for a health checkup, Homage offers house call doctor services as well , who can assess you in the comfort and convenience in your own home.

Every individual is different, and your loved one has care needs that are unique. Engaging a caregiver for your loved one not only encourages interaction; it also helps build a strong emotional support for your loved one.

To give your loved one the best care he/she deserves, we provide a free care consultation for you and your loved one, to ensure that they get a Care Professional that best suits their needs.

Causes of hypothyroidism

Now you may ask, what causes an underactive thyroid?

Hypothyroidism can result from both common and uncommon causes.

Common causes of hypothyroidism include:

Autoimmune disease

One of the most common causes of hypothyroidism is an autoimmune disorder called Hashimoto’s thyroiditis. Autoimmune disorders refer to when your body’s immune system malfunctions and attacks your own body tissues, mistaking them for foreign invaders like bacteria or viruses.

When the thyroid is targeted, Hashimoto’s thyroiditis occurs. In this disorder, the thyroid is destroyed over time, leading to a gradual loss of function and hormone production. While the exact root causes are unclear, it could be due to a combination of genetic and environmental factors.

Over-response to hyperthyroidism treatment

Radioactive iodine or anti-thyroid medications are often used to treat those who experience hyperthyroidism, or an overactive thyroid. Ironically, while the aim of these treatments is to recalibrate your thyroid function back to normal, sometimes it can go wrong as well.

Over-correction of hyperthyroidism can result in lowering thyroid hormone production too much, causing permanent hypothyroidism. It is important to therefore follow medical advice strictly and be disciplined with your medication regime.

Thyroid surgery

If you have thyroid cancer, uncontrolled hyperthyroidism, or large goiters, or thyroid nodules that severely impact your breathing and swallowing, your doctor may recommend that you undergo thyroid surgery.

Unfortunately, the removal of your thyroid, whether partial or whole, can dampen or stop thyroid hormone production. In this case, the hypothyroidism that results may require you to be on thyroid hormones for life.

Radiation therapy

Radiation therapy used to treat cancers of the head and neck can impact your thyroid function and lead to hypothyroidism.


It is also possible for certain medications that you take for other conditions to affect your thyroid and contribute to hypothyroidism. An example of such a medication is lithium which is used to treat certain psychiatric disorders.

If you suspect that you have hypothyroidism or are certain that you are, you may wish to consult your doctor about your current medication regime and prescriptions to check if any of them are impacting your thyroid functioning. If needed, discuss alternatives with your doctor.

Uncommon causes of hypothyroidism:

Congenital Hypothyroidism

Congenital Hypothyroidism refers to when a baby is born with a deficiency in producing the thyroid hormone, thyroxine. Defects in the development of the  thyroid can lead to an absent, poorly developed, or an abnormally positioned thyroid. Most cases of congenital hypothyroidism are detected through compulsory newborn screenings before symptoms develop.

Secondary hypothyroidism

Hypothyroidism primarily occurs because of the thyroid’s own deficiency in producing hormones. Sometimes, however, it can be the result of the pituitary gland.

Relatively rare, secondary hypothyroidism occurs when due to a benign tumour, the pituitary gland fails to produce enough thyroid-stimulating hormone (TSH) to signal the thyroid to produce thyroid hormones.


It is possible for some women to develop hypothyroidism during or after pregnancy due to autoimmune responses to their thyroid. Left untreated, hypothyroidism has serious consequences for both mother and child.

It increases the risk of miscarriage, premature delivery and preeclampsia —heightend blood presure in the last three months of pregnancy, and affect foetal development. In postpartum hypothyroidism, your symptoms may clear up on their own, but that is not guaranteed and medical advice should be sought in all cases.

Iodine deficiency

Found primarily in seafood, seaweed, and iodized salt, iodine is an essential mineral for the body and is necessary for the thyroid to produce thyroid hormones. Consume too little and you may develop hypothyroidism. Consume too much, however, and you may worsen your hyperthyroidism.

Iodine deficiency is relatively uncommon in developed countries like Singapore, where iodine-rich foods are abundant and readily available for consumption. Nevertheless, make sure to speak to your doctor, if you feel that your current diet or dietary restrictions may be contributing to your hypothyroidism.

Hypothyroidism risk factors

Although it is possible for anyone to develop hypothyroidism, you are at additional risk of hypothyroidism if you:

  • Are female
  • Are older than the age of 60
  • Have a family history of thyroid disease
  • Have an autoimmune disease, such as Type I diabetes or celiac disease
  • Undergoing treatment with radioactive iodine or anti-thyroid medication
  • Received radiation therapy to your neck and upper chest areas
  • Have had had thyroidectomy, or thyroid surgery
  • Have experienced pregnancy or delivered a baby within the last six months

If you’d like to discuss or manage your risks for hypothyroidism, our Homage Care Advisors and Care Specialists are available to assist you at 6100 0055.

Complications of hypothyroidism

While some of its symptoms seem harmless enough, hypothyroidism can have some serious medical consequences if left untreated.

Here are some of the complications of hypothyroidism :


The constant stimulation of your thyroid to produce more hormones can cause it to become enlarged — a condition known as a goiter. Although typically not uncomfortable, a large goiter can alter your  appearance and may cause problems with swallowing or breathing.

Heart problems

As hypothyroidism can result in high blood cholesterol levels, it may also be associated with a heightened risk of heart disease and heart failure, by extension.

Mental health issues

Depression is a serious mental health issue that can occur early on in the onset of hypothyroidism and gradually worsen over time. Slowed mental functioning can also result from hypothyroidism. If you are experiencing any of such mental health complications from hypothyroidism, it is important that you seek medical advice immediately.

Peripheral neuropathy

In the long term, uncontrolled hypothyroidism can damage your peripheral nerves, leading to  peripheral neuropathy. Responsible for carrying information from your brain and spinal cord to the rest of your body, when these nerves are damaged, affected areas may experience pain, numbness, and tingling.


Myxedema is a rare and lethal condition that results from long-term undiagnosed hypothyroidism. Signs and symptoms include extreme cold intolerance, drowsiness, profound lethargy and finally, unconsciousness.

Myxedema comas may be triggered by sedatives, infection or other stresses on your body. Seek immediate medical treatment if you experience any symptoms of myxedema.


Low thyroid hormone production can interfere with ovulation, which impairs fertility. Additionally, other causes of hypothyroidism, such as autoimmune disease may also have a negative impact on your fertility. You should talk to you doctor about any fertility issues that you may be experiencing together with your hypothyroidism to find a suitable remedy.

Birth defects

Children born to women with untreated thyroid disease run a heightened  risk of birth defects compared to babies born to healthy mothers. These children are also more susceptible to serious intellectual and developmental problems.

Untreated congenital hypothyroidism in infants can severely impair physical and mental development  but early diagnosis within the first few months of life provide excellent chances of normal development.

Hypothyroidism diagnosis

Diagnosing hypothyroidism usually depends on a blood test for thyroid-stimulating hormone (TSH), a hormone produced by your pituitary gland to encourage your thyroid to produce more thyroid hormones.

You have hypothyroidism if your TSH levels are unusually high as your body is trying to compensate for the low thyroid hormone production by stimulating your thyroid.

Your doctor may also recommend a thyroxine  test to diagnose your hypothyroidism. As one of the hormones produced directly by the thyroid, low thyroxine levels together with high TSH levels are fair indicators that you have hypothyroidism.

Thyroid treatment

Hypothyroidism is usually a lifelong condition that requires long-term treatment and daily medication. The condition is best treated with the thyroid medication, levothyroxine, or synthetic thyroxine.

Mimicking the action of thyroxine in your body, the medication is designed to return your thyroid hormone levels to normal. Once this happens, your symptoms are likely to disappear or at the very least, become much more manageable.

It can take up to several weeks after treatment starts before you are able to experience relief from your symptoms. Be patient and work with your doctor to find a suitable dose and treatment plan that provides the best relief for you.

Your doctor will recommend that you undergo regular TSH blood tests to monitor your progress in the initial treatment period and then annually to see if any adjustments have to be made to your dosage.

In order to get levothyroxine in Singapore, you must first obtain a prescription from a General Practitioner, or a clinic. You can then get your medication from local pharmacies, polyclinics or public hospitals in Singapore.

Getting regular medication at these places can be a hassle, however, with long queues and waiting times that sometimes you just don’t want to have the patience for.

For your added convenience and safety especially in a post Covid-19 world, Homage now offers thyroid treatment and medicine delivery anywhere in singapore. Within the same day, you can have your doctor’s consultation and your medication delivered to your doorstep.

Hypothyroidism diet

Other than medical treatment, you should also be aware of some dietary tips to help you manage your hypothyroidism:

Maintain a balanced diet

Your thyroid needs the right amount of iodine to function properly, but supplements are not usually necessary. Simply eat a balanced diet with whole grains, beans, lean proteins, and colorful fruits and vegetables. Try to also discover other iodine-rich foods and have fun experimenting with your diet.

Monitor your soy consumption

Soy can hinder your body’s ability to absorb thyroid hormones, and so it is best to refrain from eating too many soy products, to ensure that your medication is properly absorbed.

Soy can be found in tofu, vegan cheese and meat products, soybeans, and soy sauce. You should avoid consuming such foods at least four hours before and after taking your medication.

Having knowledge is the first step towards addressing any medical condition that we may have. Now that you know more about hypothyroidism, you’re ready to spot and remedy any symptoms that you may have.

This article was first published in Homage.

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