An underactive thyroid gland or hypothyroidism may go unnoticed in the early stages, often manifest only in the form of sudden weight loss or fatigue. If untreated, hypothyroidism can lead to several health issues such as infertility, obesity, joint pain, and heart disease.  

The thyroid is a butterfly-shaped gland located in the front of the neck. It is roughly two inches in size and practically influences every organ in the body. It secretes a hormone known as thyroxine that controls heart rate, body temperature, blood pressure, and metabolism.  

The thyroid gland requires proper regulation lest it produces too much or too little thyroxine. This is regulated by the pituitary gland and hypothalamus in the brain. When the pituitary gland senses a fall in the thyroxine levels, it secretes a hormone called thyroid-stimulating hormone (TSH), which helps in restoring the levels of thyroxine as per the body’s needs. The pituitary gland, in turn, is regulated by thyrotropin stimulating hormone (TRH), secreted by the hypothalamus.

What causes hypothyroidism?

Iodine deficiency: The thyroid gland needs iodine as an essential element to produce thyroid hormones. Iodine deficiency in the diet can affect the production of hormones.

Damage to the pituitary gland: Your pituitary gland sends signals to your thyroid gland to produce hormones. If the pituitary is damaged due to tumor, trauma, or surgery, its ability to give the thyroid the right signals will be affected.

Surgery: If you have thyroid cancer, thyroid nodules, or an overactive thyroid, you may need to surgically remove a part of the entire thyroid gland. This could cause permanent hypothyroidism.

Radiation therapy: If you have been diagnosed with head and neck cancer, thyroid cancer or an overactive thyroid, you would undergo radiation therapy. Radiation destroys thyroid cells and their capability of producing the hormone, resulting in hypothyroidism.

Medication: Some medicines can interrupt the thyroid’s ability to produce hormones. Medications that contain Lithium, prescribed for psychiatric disorders, are an example.

Autoimmune disease: Hashimoto’s disease is considered to be one of the most common causes of hypothyroidism. It is an autoimmune condition in which the immune system accidentally attacks the thyroid cells, rendering them inflamed and damaged. As a result, the thyroid cells cannot produce thyroxine properly.

Congenital hypothyroidism: In India, one in 2,640 infants is diagnosed with congenital hypothyroidism. Either the newborn is unable to produce functional hormone or a part of the entire gland is in the wrong location (ectopic thyroid). It leads to severe mental and physical difficulties if not detected and treated at an early stage.

Signs and symptoms 

Hypothyroidism symptoms may range from mild to severe. It worsens existing health conditions by slowing down key processes such as regulation of temperature, energy production, and heart rate. This leads to fatigue, tiredness, and slower bowel movements. Due to less heat generation, your basal temperature (your temperature when you are fully at rest) drops, making you feel cold. As the body converts lesser calories into energy due to slow metabolism, the rest gets stored as fat. This might lead you to put on some weight as well.

Some characteristics associated with hypothyroidism are:

• Fatigue
• Depression
• Constipation
• Feeling cold
• Dry skin
• Weight gain
• Muscle weakness
• Slowed heart rate
• Elevated blood cholesterol
• Dry, thinning hair
• Impaired memory
• Menstrual irregularities, often very frequent heavy bleeding 
• Infertility 
• Hypothyroidism and depression are very often confused with each other

Diagnosis

A blood test called thyroid profile is the mainstay to diagnose and treat hypothyroidism. The test reflects values of thyroid hormones T3 and T4 and also of the pituitary hormone TSH. A physician can diagnose a thyroid disorder based on these results. 

Additional tests to check blood cell counts, glucose, and cholesterol levels are also conducted before treatment. An ultrasound of the thyroid gland or few radioisotope studies may be required in some cases.

Treatment

Hypothyroidism is a lifelong condition requiring follow-up and treatment. Its symptoms can be reduced with medications and a healthy lifestyle.

Medications: Since your thyroid cannot produce enough hormones, it can be treated by replacing the hormone with medication. Synthetic versions of the T4 hormone imitate the function of thyroxine and are commonly used to alleviate the symptoms of hypothyroidism.

Diet: Following a healthy, nutritious diet that helps your digestive and circulatory systems, is key. Along with protein-rich foods like fish and beans, you should consume fruits, vegetables, and whole grains. If your hypothyroidism is caused by a deficiency of iodine, you would need to consume iodine-rich seafood or iodized salt. Cruciferous vegetables like broccoli, cabbage, and cauliflower should be avoided as they contain goitrogens that hamper iodine absorption by the thyroid gland.

Exercise: Hypothyroidism can cause you to have constant fatigue, weight gain, and stiff joints. A great way to manage your symptoms and boost your metabolism is to exercise. A recent study showed that hypothyroid patients doing regular exercise had increased levels of circulating thyroid hormones. Exercise improves cardiac health and helps in dealing with depression. Moderate-level exercises such as walking, yoga, pilates, aerobics, biking, along with regular medications, can help with hypothyroidism.

Hypothyroidism is a manageable condition if you follow a mindful diet and exercise regime coupled with medications. Don’t hesitate to seek medical attention if you notice significant changes in your body.

References
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