The thyroid gland is a small butterfly-shaped gland in the neck, just in front of your windpipe. Thyroid gland makes thyroid hormones. Thyroid hormones are essential for helping your body use energy (i.e. your metabolism), stay warm and keep the brain, heart, muscles, and other organs working as they should. Thyroid hormones affect nearly every organ in your body, and without it, your body’s functions would slow down.
When your thyroid ‘quits’
Hypothyroidism, or underactive thyroid, happens when your thyroid gland does not make enough thyroid hormones to meet your body’s needs. As a result, a myriad of problems may occur to your body.
The symptoms of hypothyroidism vary widely; some people have no symptoms, while others have dramatic symptoms or, rarely, life-threatening symptoms. The symptoms of hypothyroidism are notorious for being vague and for being similar to normal changes of aging, hence it can be less intuitive to tell immediately. A thyroid screening test is warranted if you or your doctor suspects hypothyroidism.
(Okay no, hypothyroidism won’t make you age overnight. But it certainly can affect how much you enjoy your life!)
With that being said, people with underactive thyroid may experience any of the following before receiving treatment:
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Slowing in metabolism, which can be manifested as fatigue, sluggishness, slight weight gain, and intolerance of cold temperatures.
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Skin and hair: your skin may dry out and become flaky, your may also sweat less. Your hair may become thinner or coarse, and eyebrows may disappear. Your nails can become brittle.
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Eye: Mild swelling around the eyes
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Heart: Lack of thyroid hormones slows your heart rate and weakens your heart’s contraction. As a result, your heart’s function is reduced, and you may experience fatigue or shortness of breath when exercising.
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Breathing: Underactive thyroid weakens the muscles that help you breathe and reduces your lung function. Symptoms can include fatigue, shortness of breath with exercise, and decreased ability to exercise. It can also lead to swelling of the tongue, hoarse voice, and sleep apnea, a sleep disorder that is characterised by excessive snoring and gasping for air during sleep.
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Gut health: Hypothyroidism slows the actions of the digestive tract, causing constipation. Rarely, the digestive tract may stop moving entirely.
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Woman’s reproductive health: Women with hypothyroidism often have menstrual cycle irregularities, ranging from absent or infrequent periods to very frequent and heavy periods. The menstrual irregularities can make it difficult to become pregnant, and pregnant women with hypothyroidism have an increased risk for miscarriage during early pregnancy. Treatment of hypothyroidism can decrease these risks.
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Muscle aches and joint pain
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Higher cholesterol levels
Individuals with hypothyroidism who received treatment should no longer experience any of the above. If they do, it is likely that they have causes other than an underactive thyroid gland. Talk to a healthcare professional when in doubt.
What causes hypothyroidism?
In the majority of the cases, hypothyroidism is due to a problem in the thyroid gland itself and is called primary hypothyroidism. Examples of primary hypothyroidism are Hashimoto’s thyroiditis and atrophic thyroiditis, both of them are a form of autoimmune disease that leads to the inflammation of the thyroid gland. This happens when the immune system that protects the body from invading infections can mistake thyroid gland cells and their enzymes for ‘invaders’ and start attacking them.Thyroid cells and enzymes are destroyed in the process and there are not enough of them left to make thyroid hormones.
Besides, certain medications and diseases can also decrease thyroid function. As an example, hypothyroidism can also develop after medical treatments for hyperthyroidism (i.e. overactive thyroid, which is a topic for next time!). In short, to treat overactive thyroid, some patients need to undergo surgery or radiation treatment to remove their thyroid gland, causing them to develop hypothyroidism instead. In some cases, hypothyroidism is a result of decreased production of thyroid-stimulating hormone (TSH) by the pituitary gland (called secondary hypothyroidism).
In addition, medicines such as:
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Amiodarone - used to treat atrial fibrillation (irregular heartbeat),
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Lithium - used to treat bipolar disorder,
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Interferon alpha - used in treatment of many cancers , and
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Interleukin-2 - used in treatment of metastatic cancers and leukemia
can prevent the thyroid gland from being able to make hormones normally. These drugs are most likely to trigger hypothyroidism in patients who have a genetic tendency to develop autoimmune thyroid disease.
Iodine is essential for the production of thyroid hormones. Therefore, taking too little iodine may result in iodine deficiency, causing hypothyroidism. The primary source of iodine is the diet via consumption of foods that have been fortified with iodine, including salt, dairy products and bread, or that are naturally abundant in iodine, such as seafood. Recommended daily iodine intake is 150 μg in adults who are not pregnant or lactating. However, for people with a damaged thyroid, taking too much iodine can lead to, paradoxically, hypothyroidism.
Both men and women can have an underactive thyroid, although it's more common in middle-aged and older women. Children can also develop an underactive thyroid and some babies are born with it, which is known as congenital hypothyroidism. In Malaysia’s hospital, all newborn babies will be screened for congenital hypothyroidism upon birth or at 5th day of life. This is carried out by taking a blood sample from the umbilical cord and sending it for lab screening.
How is hypothyroidism diagnosed?
Symptoms of hypothyroidism develop slowly and are not easy to catch. If you think you might have an underactive thyroid, you are encouraged to see a doctor.
Many symptoms of hypothyroidism are the same as those of other diseases, so doctors usually can’t diagnose hyperthyroidism based on symptoms alone and would run a thyroid function test for you.
Thyroid function test is the only accurate way to find out whether you have a thyroid problem. It is done by taking your blood sample and sending it to a lab for assessing the levels of these components: TSH, Free-T4, Total-T4, T3, thyroid antibodies and thyroglobulin. We won’t get into the details of each component, but collectively they inform your doctor the status of your thyroid function.
Treatment of hypothyroidism
Hypothyroidism is treated by replacing the thyroid hormone that your own body is lacking. You will take levothyroxine, a thyroid hormone medicine that is identical to a hormone the thyroid normally makes. Your doctor may recommend taking the medicine in the morning before eating. This is because thyroid hormone is best absorbed on an empty stomach. You should not take antacids, calcium or iron supplements, or cholesterol-lowering medications at the same time, because they can interfere with thyroid hormone absorption.
Your doctor will give you a blood test about 6 to 8 weeks after you begin taking thyroid hormone and adjust your dose if needed. Each time your dose is adjusted, you’ll have another blood test. Once you’ve reached a dose that’s working for you, your health care provider will probably repeat the blood test in 6 months and then once a year.
Your hypothyroidism most likely can be completely controlled with thyroid hormone medicine, as long as you take the recommended dose as instructed. Never stop taking your medicine without talking with your health care provider first.
What should I eat or avoid eating if I have hypothyroidism?
If you have autoimmune thyroid disease such as Hashimoto’s thyroiditis, you may be more prone to the side effects from iodine. Therefore, you should limit or avoid foods that have large amounts of iodine—such as kelp, dulse, or other kinds of seaweed—as well as iodine supplements. Talk to your healthcare professionals about what foods you should limit or avoid, and let them know if you take iodine supplements. Also, share information about any cough syrups that you take because they may contain iodine.
Women need more iodine when they are pregnant because the baby gets iodine from the mother’s diet. If you are pregnant, talk with your health care provider about how much iodine you need.
Hypothyroidism gets out of hand: myxedema coma
Rarely, hypothyroidism becomes so severe that it leads to myxedema coma, a life-threatening medical emergency. People with myxedema coma may experience decreased mental status, low body temperature, low heart rate, low blood pressure, decreased breathing or coma.
Myxedema coma can cause death often due to complications from infection, bleeding, or respiratory failure.
