Thyroid hormones, produced by the thyroid gland in the neck, are essential for regulating metabolism and bodily functions. Hypothyroidism is a condition where the thyroid gland underproduces these hormones, slowing down metabolic processes. It can cause fatigue, weight gain, and cognitive issues. Understanding its causes, symptoms, and treatments is vital to prevent serious complications.
What Are Thyroid Hormones?
Thyroid hormones are produced and released by the thyroid gland. The thyroid gland is situated in the front of the neck, just below the Adam’s apple, and has a butterfly shape. This gland and its secretions are responsible for maintaining a healthy metabolism while regulating other processes in the body.
These hormones are crucial for regulating various physiological processes in the body, including metabolism, growth, and development. The main thyroid hormones are thyroxine and triiodothyronine.
The production and release of thyroid hormones are controlled by the hypothalamus and the pituitary gland through the thyroid-stimulating hormone (TSH). Imbalances can lead to disorders such as hypothyroidism or hyperthyroidism.
What Is Hypothyroidism?
Hypothyroidism is a medical condition characterised by an underactive thyroid gland, which means the gland does not produce enough thyroid hormones to meet the body’s needs. Thyroid hormones are essential for regulating metabolism, so when their levels are low, the body’s processes slow down.
Types Of Hypothyroidism
Hypothyroidism can occur in 3 ways: primary, secondary or, very rarely, tertiary hypothyroidism.
Primary hypothyroidism often occurs in society, affecting women more than men, and is referred to when there is a problem with the thyroid gland which is not producing and releasing sufficient thyroid hormones known as triiodothyronine (T3) or thyroxine (T4). This causes a decrease in the metabolic rate of the body.
Secondary hypothyroidism is not as common as primary hypothyroidism but can still occur. This is usually when there is a disturbance in the physiology of the pituitary gland, which results in the fact that the pituitary gland is not secreting sufficient thyroid-stimulating hormone (TSH) to stimulate the thyroid to secrete thyroid hormones T3 and T4.
Tertiary hypothyroidism, which is extremely rare, is caused by a problem in the hypothalamus in the brain. The hypothalamus does not produce sufficient thyrotropin-releasing hormone (TRH) to stimulate the anterior pituitary to secrete sufficient FSH in order to result in a higher secretion of T3 and T4 from the thyroid gland.
Hypothyroidism can thus be caused when there is a disturbance anywhere in this axis which can have repercussions on the body’s function and processes.
What Causes Hypothyroidism?
Hypothyroidism can be caused by various elements often leading to primary hypothyroidism. These elements that contribute to the causes include:
Hashimoto’s Disease
This is an autoimmune disease that occurs when the immune system makes antibodies that attack the thyroid cells, destroying them and leading to less production of T3 and T4. Hashimoto’s is often triggered by infection, genetic or environmental factors.
Thyroiditis
Subacute thyroiditis is inflammation of the thyroid, often following a viral infection, which can initially cause hyperthyroidism and later lead to temporary or permanent hypothyroidism. Postpartum thyroiditis is when women experience thyroid inflammation after giving birth, which can lead to temporary hyperthyroidism followed by hypothyroidism.
Thyroidectomy
This is a surgical procedure when a part or the whole thyroid is removed, usually due to cancer. The less thyroid there is, the less thyroid hormones will be produced.
Medication Or Radiotherapy
Some medications can decrease the secretions of T3 and T4 such as lithium, amiodarone, and interferon-alpha. Radiotherapy for cancer, for the head or neck area, can also affect the proper functioning of the thyroid gland.
Insufficient Iodine Intake
Iodine is needed for the thyroid to make thyroid hormones. In some cases people do not get enough iodine to make T3 and T4, resulting in low levels thereof. A balanced amount of Iodine at about 150 – 200 micrograms per day is recommended to maintain a healthy thyroid.
Congenital Defects
Some infants are born with an underactive thyroid or no thyroid gland at all. This condition can be due to genetic factors or developmental issues during pregnancy.
What Are The Symptoms Of Hypothyroidism?
When someone experiences these symptoms suddenly, it is recommended to consult a doctor. Because thyroid hormones affect nearly every part of the body, symptoms can be widespread and may include:
- Fatigue and low energy levels
- Weight gain or difficulty losing weight
- Cold intolerance
- Dry skin and hair, and hair loss
- Constipation
- Depression or mood changes
- Slow heart rate
- Muscle weakness and joint pain
- Menstrual irregularities
- Cognitive issues, such as memory problems or difficulty concentrating
What Are The Treatment Options?
Consulting with a healthcare professional for personalised treatment and management plans is crucial, as they can guide based on individual health conditions and test results.
Medication
The primary treatment for hypothyroidism is thyroid hormone replacement therapy, usually with a synthetic hormone called levothyroxine. This medication replaces the thyroid hormone T4.
The T4 will be metabolised to T3 in the bloodstream, making the thyroid hormone an active metabolite in order to replace the low levels of biological thyroid hormone.
This helps normalise hormone levels to alleviate symptoms. It is recommended to take the tablet in the morning on an empty stomach, 30 minutes before breakfast.
Treatment is typically lifelong and requires regular monitoring to adjust the dose as needed. This medication does not typically have severe side effects, but one may experience chest pain, headaches, sweat and nausea. If these side effects are unbearable, it is recommended to speak to your healthcare provider before just stopping the medication.
Diet
While there’s no specific diet to cure hypothyroidism, ensuring a diet rich in iodine (found in seafood, dairy, and iodized salt) is essential, as iodine is necessary for thyroid function. However, excess iodine can also worsen the condition, so balanced intake is key.
Avoiding certain foods like those high in goitrogens (e.g., soy products, cruciferous vegetables), as it might interfere with thyroid function if consumed in large quantities, especially if raw. Cooking these foods often reduces their goitrogenic effect.
Exercise
Exercise can help manage weight gain and fatigue associated with hypothyroidism and support overall health.
Managing Stress
Stress can impact thyroid health, so techniques like mindfulness, meditation, yoga, or other stress-relief activities may help improve general well-being.
Monitoring Other Nutrients
Selenium and Zinc are important for thyroid health. Selenium, found in foods like Brazil nuts, and zinc, found in meat and shellfish, can support thyroid hormone synthesis and function.
Deficiency in vitamin D has been linked to autoimmune thyroid conditions, so supplementation may be recommended if levels are low.
Regular Follow-Ups
Routine check-ups with an endocrinologist or primary care doctor help track treatment efficacy and symptom control, allowing adjustments in therapy as needed.
What Are The Potential Complications Of Hypothyroidism?
If hypothyroidism is left untreated or poorly managed, it can lead to various complications, some of which can be severe. Here are the main potential complications associated with hypothyroidism:
Goitre
Persistent low levels of thyroid hormones can cause the thyroid gland to enlarge in an attempt to produce more hormones, leading to a goitre. While a goitre is usually not harmful, it can cause discomfort, difficulty swallowing or breathing, and cosmetic concerns.
Heart Problems
Increased Cholesterol Levels: Hypothyroidism can lead to higher levels of low-density lipoprotein (LDL) cholesterol, contributing to the risk of atherosclerosis (hardening of the arteries).
Pericardial Effusion: Fluid accumulation around the heart can occur, impacting heart performance.
Cardiovascular Disease: The condition can increase the risk of heart disease and heart failure due to the effects on cholesterol and heart function.
Mental Health Issues
Hypothyroidism can lead to depression and low mood, which may become more severe if left untreated. Individuals may experience slowed mental functioning, memory problems, or difficulty concentrating, often referred to as “brain fog.”
Myxedema
Myxedema is a rare but life-threatening condition that can occur if hypothyroidism goes untreated for a long period. Symptoms include extreme fatigue, drowsiness, intense cold intolerance, and even coma.
Myxedema coma is a medical emergency and requires immediate treatment. Myxedema is also associated with skin changes, including thickening and swelling, especially around the face and lower legs.
Infertility And Reproductive Issues
Hypothyroidism can disrupt the menstrual cycle, making it harder to conceive. Untreated hypothyroidism during pregnancy can lead to complications such as preeclampsia, anaemia, miscarriage, premature birth, or low birth weight. It can also affect the baby’s development, leading to potential intellectual and developmental problems.
Peripheral Neuropathy
Long-term untreated hypothyroidism can cause damage to the peripheral nerves, leading to pain, tingling, or numbness in the extremities.
Muscle And Joint Pain
Muscle aches, joint pain, and stiffness can occur due to slowed metabolism and decreased energy levels.
Obesity And Weight Gain
Reduced thyroid hormone levels can slow metabolism, leading to weight gain and difficulty losing weight. This can contribute to obesity and related health conditions, including metabolic syndrome.
Developmental Issues In Children
In children, untreated hypothyroidism can result in delayed growth, cognitive impairments, and delayed puberty. Severe hypothyroidism in infancy or childhood can lead to cretinism, a condition marked by stunted physical and mental development.
Anaemia
Hypothyroidism can be associated with a type of anaemia characterised by reduced production of red blood cells, contributing to fatigue and weakness.
Fluid Retention And Edema
Fluid accumulation in body tissues can lead to puffiness, especially around the eyes and face.
