HypothyroidismAlso known as Underactive thyroid
Hypothyroidism is a condition in which the thyroid gland does not produce sufficient quantities of thyroxine, a thyroid hormone. Due to the low levels of this hormone, the person may experience various symptoms such as fatigue, unexplained weight gain, difficulty losing weight, reduced tolerance to cold, puffiness of the face, hoarseness of voice, excessive hair fall, muscle and joint pains, fertility problems, or depression.
There are numerous conditions that can lead to a low thyroid level such as autoimmune thyroiditis, iodine deficiency, pregnancy, radiation therapy, and surgical removal of the thyroid gland. Although this condition is common in women, men can also suffer from it.
Fortunately, hypothyroidism is generally manageable with inexpensive medications after timely diagnosis. If left untreated, it may lead to complications such as obesity, goiter, infertility, and heart failure. Hence, patients especially those at high risk should keep a close watch on the symptoms of hypothyroidism.
- Adults above 60 years of age
- Both men and women but more common in women
- Thyroid gland
- Peripheral nerves
- Reproductive system
- Addison’s disease
- Chronic fatigue syndrome
- Polycystic ovarian disease (PCOD)
- General physician
Symptoms Of Hypothyroidism
Initially, hypothyroidism may not cause any symptoms. The symptoms often appear gradually and may not be noticeable in the earlier stages. There are various symptoms associated with hypothyroidism such as:
Unexplained weight gain and difficulty losing weight
Puffiness of the face
Hoarseness of voice
Disturbances in the menstrual cycle in women
Fertility problems in women of child-bearing age
Excessive hair fall, hair may become brittle, dry, and break easily
Muscle and joint pains
Elevated blood cholesterol levels
Reduced tolerance to cold
Thyroid gland enlargement (Goiter)
Hypothyroidism can also affect infants, young children, or teens, causing symptoms such as:
Delayed onset of puberty
Lethargy and sleepiness
Note: Infants may be born without a thyroid gland or with a poor-functioning gland and cause specific symptoms such as constipation, difficulty breathing, protruding tongue, and jaundice.
Causes Of Hypothyroidism
There are two hormones involved in hypothyroidism --thyroid stimulating hormone (TSH) and thyroxine. TSH is a hormone secreted by the pituitary gland in the brain and its function is to stimulate the thyroid gland to produce thyroxine.
Hypothyroidism is a hormonal disorder where the thyroid gland does not produce sufficient quantities of the thyroid hormone. Hypothyroidism is clinically evaluated by the levels of TSH and free thyroxine concentrations. TSH levels are higher than than the reference range while thyroxine levels are below the reference range.
A. Clinical primary hypothyroidism
Primary hypothyroidism is caused by a problem with the thyroid gland itself. Hypothyroidism is caused when the thyroid gland does not produce sufficient quantities of the thyroid hormone or thyroxine. Multiple causes may lead to the underproduction of the thyroid hormone such as:
1. Autoimmune disease
In this, the immune system makes antibodies that attack the thyroid gland. As a result, large numbers of white blood cells, which are part of the immune system, attack the gland and damage it and cause insufficient production of thyroid hormones. The most common forms are Hashimoto’s thyroiditis (chronic lymphocytic thyroiditis) and atrophic thyroiditis.
2. Iodine deficiency
Iodine is an essential mineral required by the thyroid gland to produce thyroxine. A deficiency of iodine in the diet causes the underproduction of the thyroid hormone.
During or post pregnancy, there may be an inflammation of the thyroid gland, which may affect the production of the thyroid hormone. This condition is known as postpartum thyroiditis. However, most women with postpartum thyroiditis regain their normal thyroid function.
4. Surgical removal of thyroid gland
In some cases, people with hyperthyroidism, thyroid nodules, small thyroid cancers, large goiter or Graves’ disease, need to have part or all of their thyroid gland removed surgically. If the whole thyroid is removed, then it can lead to hypothyroidism as no thyroid hormones are produced. However, if only a part of the gland is removed, it may be possible to make enough thyroid hormones to ensure proper functioning of the body.
Certain medicines such as antipsychotic drugs like lithium, antiarrhythmic drugs like amiodarone and interleukins & anti-cancer medicines, affect thyroid hormone production. Medicines used to treat hyperthyroidism can cause paradoxical hypothyroidism.
6. Radiation therapy
Ionizing radiation is commonly prescribed to people who have hyperthyroidism or cancer of the head or neck like lymphoma or leukemia. But in some cases, exposure to the ionizing radiation exposure during the treatment of certain cancers or hyperthyroidism can damage the thyroid gland and lead to hypothyroidism.
B. Central hypothyroidism
Central hypothyroidism is defined as hypothyroidism due to insufficient stimulation by TSH of an otherwise normal thyroid gland. It can be secondary hypothyroidism (pituitary) or tertiary hypothyroidism (hypothalamus) in origin.
Rarely, the hypothalamus under-secretes the thyrotropin-releasing hormone (TRH). This affects the secretion of TSH by the pituitary gland, causing hypothyroidism. This is also known as tertiary hypothyroidism.
C. Congenital hypothyroidism
Some babies are born with a thyroid gland that is not fully developed or does not function properly, which causes hypothyroidism at birth.
Risk Factors For Hypothyroidism
The following risk factors are associated with hypothyroidism.
1. Gender: Women are more likely to develop hypothyroidism than men.
2. Age: Hypothyroidism is more common among people older than 60 years.
3. Family history: The risk is high if you have a family history of hypothyroidism or other thyroid-related disorders.
4. Race: White or Asian races are more likely to develop this disorder.
5. Medical conditions: Several health problems that can increase your risk of hyperthyroidism are:
- Type 1 or type 2 diabetes
- Multiple sclerosis
- Rheumatoid arthritis
- Sjogren’s syndrome
- Celiac disease
- Addison's disease
- Pernicious anemia
- Bipolar disorder
- Down syndrome
- Turner syndrome
Diagnosis Of Hypothyroidism
The tests essential to confirm a diagnosis of hypothyroidism are:
A. Blood tests
Some of the common blood tests used to diagnose hypothyroidism incude thyroid stimulating hormone (TSH) test & thyroxine (T3 & T4) test.
This is the most important and sensitive test for hypothyroidism. It measures how much of the thyroxine (T4) hormone the thyroid gland is being asked to make. An abnormally high TSH means the thyroid gland is being asked to make more T4 because there isn’t enough T4 in the blood. This indicates hypothyroidism. TSH also helps the doctor to determine the right dosage of medication, both initially and over time.
Most of the T4 in the blood is attached to a protein called thyroxine-binding globulin. The “bound” T4 can’t get into body cells. Only about 1%–2% of T4 in the blood is unattached (“free”) and can get into cells. The free T4 and the free T4 index are both simple blood tests that measure how much unattached T4 is in the blood and available to get into cells. In hypothyroidism, the thyroxine levels are lower than normal.
3. Thyroxine Total (T3)
The total T3 includes both bound and free forms circulating in the blood and can be affected by the amount of protein available in the blood to bind to them. The T3 hormone can be measured as free T3 or total T3. Triiodothyronine (T3) total test measures the total levels (both free and bound forms) of triiodothyronine (T3) hormone in the blood and is usually done as a part of the thyroid profile total test. Its levels may be normal or low in hypothyroidism.
Along with these three tests, supporting tests may be required to evaluate and monitor the condition such as:
Also, all newborn babies are routinely screened for thyroid hormone deficiency to rule out congenital hypothyroidism.
B. Imaging tests
The following imaging tests can be used to find the cause of hypothyroidism:
1. Thyroid scan
Thyroid scan can help to evaluate the size, shape, and position of the thyroid gland. This test uses a small amount of radioactive iodine to help diagnose the cause of hypothyroidism and check for thyroid nodules as well.
Ultrasound of the thyroid is used to closely look at thyroid nodules. Thyroid nodules are solid or fluid-filled lumps that form within the thyroid gland. Ultrasound can also help the doctor to evaluate if the nodules are cancerous in nature.
A radioactive iodine uptake test also called a thyroid uptake test, measures how much radioactive iodine the thyroid takes up from the blood after swallowing a small amount of it. It can help check thyroid function and find the cause of hypothyroidism.
Prevention Of Hypothyroidism
There is no specific way to prevent hypothyroidism. The best way to prevent complications of the disease or having the symptoms impact your life in a serious way is to watch for signs of hypothyroidism. Those who are at a higher risk for hypothyroidism must be more watchful of their symptoms. If you experience any of the symptoms, it is best to consult your doctor. Hypothyroidism is quite manageable if diagnosed and treated early.
Specialist To Visit
You must visit a doctor, if you have symptoms such as weight gain, hairfall, enlarged thyroid gland, swelling of the face and the limbs, weakness, fatigue, poor concentration, decreased libido, and difficulty getting pregnant. All these are possible symptoms of hypothyroidism. If you suspect hypothyroidism, you may consult with:
Women may need to consult obstetrician and gynecologistother, in case of specific symptoms such as hair fall, weight gain, fatigue & difficulty in getting pregnant.
Treatment Of Hypothyroidism
Hypothyroidism is treated by prescribing a synthetic version of the thyroxine hormone. The prescribed medicine must be taken every day in the morning or as prescribed by the physician. Certain medications such as iron and calcium supplements or aluminum hydroxide, which is found in some antacids, may interfere with the absorption of thyroxine.
The dosage may need to be adjusted based on the close monitoring of the TSH and thyroxine levels. The dosage of the thyroid medicine is decided by the doctor depending upon the age, cause of hypothyroidism, other concomitant health conditions or any other medications being taken by the patient. For example, the elderly population is started on a lower dose whereas a higher dose may be needed, if gastrointestinal diseases like celiac disease hamper the absorption of the medicine.
The only dangers of thyroxine are caused by taking too little or too much of the medicine. If you take too little, your hypothyroidism will continue. If you take too much, you’ll develop the symptoms of hyperthyroidism—an overactive thyroid gland. The most common symptoms of too much thyroid hormone are fatigue, inability to sleep, greater appetite, nervousness, intolerance to heat, shortness of breath, and a racing heart. Patients who have hyperthyroidism symptoms during thyroxine replacement therapy, should have their TSH levels tested. If it is low, indicating too much thyroid hormone, their dose needs to be lowered.
Home-care For Hypothyroidism
If you have hypothyroidism, you will be prescribed a synthetic version of the thyroid hormone to combat the deficiency. Here are a few tips to help you take the medicines & improve your symptoms.
It is important to take the tablet daily, preferably first thing in the morning, for as long as advised by your doctor.
You can take the tablet preferably with water and on an empty stomach.
Maintain a gap of at least 4 hours between the thyroid medicine and other medicines such as calcium or iron supplements.
To keep track of your pills, you may store them in an airtight labeled box which has labels for each day of the week. This would help you keep a track of your doses and whether you have missed any.
Taking a balanced diet that fulfills the body’s requirements of iodine may help hypothyroidism caused by iodine deficiency. Consume iodine-fortified table salt as it is a good way of including iodine in your diet. Shellfish, lean proteins & whole grains are good sources of iodine.
However, in case of Hashimoto’s disease or other types of autoimmune thyroid diseases, patients may be sensitive to side effects of iodine. Eating foods that have large amounts of iodine may actually cause or worsen hypothyroidism. Taking iodine supplements might also have the same effect. Hence, in such cases, it is important to consult a doctor about which foods to limit or avoid and whether one can take iodine supplements or other medications like cough syrups which might contain iodine.
Eat a low fat diet and include foods rich in calcium and Vitamin D such as milk and milk products & oily fish. Add leaner proteins such as chicken breast or fish.
Avoid certain vegetables like cabbage, broccoli or cauliflower as these are known to interfere with the functioning of the thyroid gland.
Limit soy food products like tofu, vegan cheese and meat products, soy milk, soybeans, and soy sauce. Soy is known to hinder the absorption of thyroid hormone. Hence, avoid eating or drinking soy-based foods for at least four hours before and after taking the medication.
Like soy, fiber can also interfere with hormone absorption. Since fiber is vital for the body do not avoid it completely. Instead, avoid taking the medication within several hours of eating high fiber foods.
Incorporating a few diet-related changes can help you manage your condition better as well as lead a healthy life. Here are a few diet tips for people with hypothyroidism that can help control the condition.
Exercise and yoga
Daily exercise and yoga can help boost the body’s metabolic rate and ease the symptoms of hypothyroidism. Regular exercise may also help battle complications of hypothyroidism including obesity, and heart-related issues. You can also engage in light exercise programs to boost your metabolism and help with the symptoms of hypothyroidism.
Some yoga asanas which are helpful in thyroid issues are:
Note: Please perform these asanas under expert supervision only.
Complications Of Hypothyroidism
Hypothyroidism can cause many health complications such as:
Constant stimulation of the thyroid gland to produce more hormones may cause the gland to swell and become larger. This is known as goiter. It appears as a cosmetic deformity in the neck and may also cause trouble while breathing or swallowing.
Even with a reduced appetite, people with hypothyroidism tend to put on weight and find it difficult to lose weight because of a slower basal metabolic rate. This predisposes them to obesity.
3. Cardiac problems
Hypothyroidism is associated with an increased risk of heart diseases or heart failure. It elevates the levels of low-density lipoprotein (LDL) which is bad for heart health.
In women, hypothyroidism can interfere with the normal cycle of production of eggs or the ovulation process and cause challenges when trying to conceive. In men, an underactive thyroid is known to cause abnormal sperm morphology and erectile dysfunction.
5. Peripheral neuropathy
Long term hypothyroidism can damage the peripheral nerves which carry information from the brain and spinal cord to the rest of the body. This causes pain, tingling, or numbness in the extremities.
This is a rare and serious complication which happens when the thyroid levels in the body are extremely low. The patient may become lethargic, drowsy, and in severe forms may slip into a coma known as myxedema coma, which can be life-threatening.
7. Balance problems
Hypothyroidism can also present with balance problems especially in older women.
8. Joint pain
Low levels of thyroid hormone can cause joint and muscle pain, as well as tendonitis which is inflammation of a tendon, the thick fibrous cords that attach muscle to bone.
9. Mental health issues
Hypothyroidism can cause slow mental functioning as well as memory or concentration lapses. Depression may also occur in hypothyroidism and may become more severe with time.
10. Birth defects
Women with untreated thyroid disease are more likely to give birth to babies with higher risk of birth defects. These children are also likely to have intellectual and developmental problems. Infants with congenital hypothyroidism, which is not treated timely, are at risk of both physical and mental development.
Living With Hypothyroidism
A diagnosis of hypothyroidism may often be a cause of anxiety for the patient as it comes with multiple health symptoms. Patients often struggle with obesity and have poor energy levels. They have heart problems such as increased cholesterol levels and heart failure. Women of reproductive age may also face problems in conceiving a child due to hypothyroidism. Hypothyroidism is also known to cause chronic depression. All this may affect patients' quality of life. Fortunately, hypothyroidism is generally manageable with inexpensive medications. If your thyroid hormone levels are low, a simple treatment along with the following tips could greatly improve your quality of life.
1. Lose weight
If you have low thyroid levels, you may have decreased metabolic rate and a higher body mass index (BMI), which can put you at risk of obesity. And if you are overweight, you may need more thyroid hormone to carry out the regular functions.
A low-calorie diet can help you to lose weight and in extreme cases, weight loss surgery can also help. Talk to your doctor about the options available to lose weight and how it can improve your thyroid function and disease control.
2. Eat a balanced diet
A healthy diet can help you to deal with certain symptoms of hypothyroidism such as lethargy, fatigue, and tiredness. Eating well also lowers your risk of developing other health complications due to the impaired thyroid gland.
Eat foods rich in selenium, omega-3 fatty acids, calcium, magnesium, and vitamins E and B6. Load up your intake of fresh fruits and vegetables, whole grains, and lean meat and stay away from processed foods.
3. Exercise without fail
As hypothyroidism makes you feel tired and low on energy, it is important to ensure you stay physically active. This can not only improve your metabolism but can also improve your overall health right from aiding in weight loss to helping you manage your condition.
You can start slow by walking in the morning and evening or playing a sport. Swimming or riding a cycle is not a bad idea as it can help you to move and stay active. You can even consider yoga as it involves stretching and twisting of the muscles which can stimulate the thyroid gland and also help you to maintain a healthy metabolism.
4. Take medications regularly
Strictly follow your doctor’s advice about taking these medications regularly and on time. Do take your medicines daily at almost the same time to ensure a consistent level of hormones in the blood throughout the day.
The best time to take thyroid medications is early in the morning. But, do not take it with tea or coffee as you need to maintain a gap of at least 30 minutes between food items and this medicine. It is wise to keep a reminder to take medicines to avoid skipping medications.
5. Manage stress
When you are stressed, there are numerous hormonal changes that happen in the body. These changes not only increase the resistance of thyroid receptor cells to thyroid hormones but also weaken your immunity. So, there is no two-way when it comes to managing stress and hypothyroidism.
Certain measures that can help you de-stress include indulging in a hobby, meditation, joining a dance or art class, gardening, planning a mini-vacation, spending time with friends and family, etc.
Pregnancy and hypothyroidism
Hypothyroidism is very common during pregnancy and can pose a significant threat to the health of both mother and the baby. With hypothyroidism, the mother may be at an increased risk of miscarriages, hypertension, anemia, muscle pain, etc. Whereas, the baby may have a possibility of cognitive and developmental impairments.
Women with hypothyroidism need an increased dosage of the thyroid medicine for the duration of their pregnancy and they must consult their doctor regarding the same as soon as pregnancy is confirmed. It is also essential to undergo routine monitoring tests for the levels of TSH and thyroxine to optimize the treatment dosages.
Here’s more on the wider range of implications, symptoms, and measures that need to be taken for hypothyroidism during pregnancy.
Frequently Asked Questions
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