What Is the Thyroid? What Are Its Problems and Treatment Methods?

The endocrine system consists of hormones and endocrine glands with a secretory function. Hormones with important roles in the body are released from endocrine glands into the bloodstream and carried by the blood to organs, muscles and skin. Hormones delivered to tissues help keep systems working regularly through various signals.

One of the endocrine glands that contributes to the management of metabolic processes is the thyroid gland.

The thyroid gland is located in the front of the neck, in front of the windpipe. It extends to both sides of the throat, is butterfly-shaped and is generally not noticeable from the outside. Stimulated by signals from the hypothalamus and pituitary gland, the thyroid gland and its hormones can affect the functioning of almost all organs in the body. The circulatory system, including the heart and blood vessels, the digestive system, the reproductive system and the nervous system are systems affected by thyroid hormones. When the thyroid gland does not work properly, problems can arise in one or more organs or systems.

What Is the Thyroid Gland and What Is Its Function?

The thyroid gland, part of the endocrine system, contributes to the regulation of many events in the body through the hormones it secretes. The main function of the thyroid is the functioning and control of metabolism. It supports the development of the brain and nerves, the regulation of pulse and breathing, fertility, and the functioning of bones, hair, skin, eyes, heart and intestines.

Thyroid hormones are released into the bloodstream regularly in constant amounts. When more energy is needed in the body (during growth and pregnancy, etc.), more thyroid hormones are produced. As a result of signals from the hypothalamus and pituitary gland, the thyroid gland produces 3 hormones and secretes them into the blood:

Thyroxine (T4): The main hormone produced by the thyroid. After entering the circulation, thyroxine is converted into the active thyroid hormone triiodothyronine.

Triiodothyronine (T3): Produced in smaller amounts than thyroxine, but has a greater effect on metabolism.

Calcitonin: Helps regulate the amount of calcium in the blood and bones.

T3 and T4 hormones can be effective in increasing the basal metabolic rate and stimulating cells to work harder. The thyroid gland needs iodine to produce thyroid hormones. Iodine found in table salt, various foods and water is taken up by the thyroid gland and used during the production of thyroid hormones. Therefore, the amount of iodine in the body can affect the levels of hormones produced. In our country, water and other foods are poor in iodine.

What Are Common Thyroid Diseases?

Thyroid diseases can generally arise from insufficient or excessive production of hormones. Thyroid diseases have several different types and can be classified as primary and secondary depending on their cause. Primary thyroid diseases are directly related to the thyroid gland, while secondary thyroid diseases originate from the pituitary gland. The main diseases affecting the thyroid can be listed as follows:

Hypothyroidism: In an underactive thyroid gland, sufficient amounts of thyroid hormones cannot be produced. Therefore, insufficient hormone levels can cause a slowing of metabolism. Common symptoms include sensitivity to cold, fatigue, weight gain, constipation, depression, dry skin, facial puffiness and irregular menstrual periods.

Hyperthyroidism: Excessive thyroid hormone production resulting from an overactive thyroid gland. Excessive thyroid hormone production can cause acceleration of metabolism and increased energy use in the body. Common symptoms include heat sensitivity and sweating, weight loss, nervousness, palpitations, difficulty sleeping, thin and brittle hair, and irregular menstrual periods.

Thyroid nodules: Lumps formed by abnormal growth or proliferation of thyroid cells. Thyroid nodules can be single or multiple, and solid or fluid-filled. Nodules are usually benign and rarely cause cancer. They usually do not cause symptoms; however, excessively enlarged nodules can press on the windpipe and esophagus, causing neck swelling, hoarseness, shortness of breath and difficulty swallowing.

Since thyroid hormones affect body temperature, heartbeat, energy metabolism and similar functions, symptoms such as palpitations, intolerance to heat or cold, and weakness should be followed closely and an endocrinologist should be consulted.

What Are the Causes and Risk Factors of Thyroid Disease?

Thyroid disorders can arise from various causes. Autoimmune diseases, genetic characteristics, and environmental factors such as iodine and radiation are the main factors associated with problems in the thyroid gland and its hormones. Factors that can cause hypothyroidism, which occurs when the thyroid gland is underactive, may include:

Hashimoto's disease, an autoimmune disorder,

Iodine deficiency in the diet,

Pituitary gland problems,

Overtreatment of hyperthyroidism,

Thyroid inflammation,

Removal of the thyroid gland.

Conditions that can cause hyperthyroidism, which occurs when the thyroid gland is overactive, are as follows:

Graves' disease, an autoimmune disorder,

Thyroid nodules,

Excess iodine in the blood due to diet or medications,

A benign tumor of the pituitary gland,

Overtreatment of hypothyroidism.

Diagnostic methods for thyroid diseases are varied. The first methods that provide information about thyroid health are physical examination and blood tests. In a physical examination, the size of the thyroid gland is checked and nodules are detected. The TSH hormone level in the blood is considered an indicator for both hypothyroidism and hyperthyroidism. The normal TSH range is 0.5-5.0 mIU/L, and this value may vary depending on factors such as age and pregnancy. Blood tests can also measure levels of free T3 and T4 hormones.

If hormone levels are abnormal, imaging methods may be used. Ultrasonography can be used to examine the size of the thyroid gland and to evaluate suspected thyroid nodules. Fine-needle aspiration biopsy (FNAB) is the gold standard test for diagnosing thyroid nodules. Scintigraphy can be performed to detect thyroid and nodule activity in cases of hyperthyroidism and similar conditions.

What Are the Treatment Options for Thyroid Diseases?

Depending on the severity of the hormone imbalance and the underlying cause, there are several treatment options. The three main treatments used for thyroid diseases are medication therapy, surgery and radioactive iodine therapy.. Medication treatments can help suppress the high hormone production of the thyroid caused by hyperthyroidism and help correct symptoms. Today, ablation treatments have also become available for benign thyroid nodules. Treatment options, which vary according to the type of thyroid disease, may include:

Hypothyroidism: When the thyroid gland cannot produce sufficient amounts of thyroid hormone, synthetic forms of the thyroid hormones the body needs can be used as medication.

Hyperthyroidism: Drug therapy brings the thyroid's hormone production back to normal, thereby correcting symptoms such as palpitations. Radioactive iodine therapy damages thyroid cells, destroying the thyroid gland. In uncontrolled hyperthyroidism, surgery may be performed.

Thyroid nodules: In newly diagnosed nodules, in young patients, and in regions with iodine deficiency, medication therapy may be applied. Observation should be maintained during diagnosis and treatment. If nodules press on various tissues in the throat, surgery may be recommended.

Removal of the thyroid gland may be necessary in some cases, and this procedure is called “thyroidectomy”. In thyroid cancer cases, thyroidectomy and, in some cases, additional radioactive iodine therapy may be applied.

What Are the Lifestyle Recommendations for Patients with Thyroid Problems?

Iodine intake is needed for the healthy functioning of the thyroid gland and its hormones. Since iodine cannot be produced in the body, it must be taken in through food. Consumption of iodized salt and iodine-rich foods can provide sufficient iodine. Foods containing iodine include fish and seafood, milk and dairy products, soy milk and soy sauce, eggs and meat. For individuals with iodine deficiency, increasing iodine intake is important, and for individuals with Hashimoto's disease, avoiding excessive iodine intake is important. During and after treatment, hormone levels should be monitored and appropriate dietary management should be provided.

People who do not engage in regular physical activity have higher TSH hormone values compared to those with regular activity. Rising TSH levels and an increased risk of hypothyroidism may be related to lifestyle habits. In addition, hormonal changes in the body during periods of stress and depression can also affect thyroid activity. Women in particular encounter hormone imbalances more frequently, and when the thyroid is affected, symptoms such as irritability, restlessness and depression may occur. Lifestyle changes should be reviewed in the prevention and treatment of thyroid disorders.

Frequently Asked Questions About the Thyroid

Because thyroid hormone levels and thyroid diseases can be complex or unpredictable, they often raise many questions. You can read on for answers to the most frequently asked questions about thyroid hormones and thyroid problems. Thyroid enlargement or nodules are generally not dangerous. However, although rarely, they can be cancerous. The cancer rate in thyroid nodules varies between approximately 3-5%. Having hyperthyroidism or hypothyroidism does not change the likelihood of thyroid cancer. However, exposure to radiation, especially in the head and neck regions, can increase cancer risk. Having a family history of thyroid patients can affect the occurrence of thyroid diseases in other family members. People with a family history of thyroid problems have a higher risk of developing thyroid problems. For this reason, routine monitoring of the thyroid gland and its hormones is recommended.

During pregnancy, many physiological changes occur in the female body. Hormonal and metabolic changes that occur during pregnancy can affect thyroid hormone values and may mimic some thyroid diseases. During pregnancy, production of TSH and T4 hormones may increase somewhat, and thyroid enlargement may be seen. Furthermore, pregnancy can also change the course of existing thyroid diseases. Since the course of thyroid diseases that continue during pregnancy can affect the newborn, diagnosis and treatment should be carried out as early as possible. Additionally, hypothyroidism may be associated with decreased fertility in women. Low thyroid hormone levels can adversely affect ovulation and reduce fertility. If thyroid diseases are present before or during pregnancy, it is important to treat them.

The presence of thyroid problems in the family, involuntary changes in weight, changes in heart rate and sensitivity to temperature, fatigue and similar factors require monitoring of thyroid hormone levels. In addition, sleep problems, a palpable lump, and irregular menstrual periods in women may also give clues about thyroid function. In such cases, checking thyroid hormone levels is recommended.

Thyroid disorders are seen more frequently in women than in men. This can be attributed to female hormonal patterns and changes. Thyroid diseases are common especially in women between puberty and menopause. Estrogen present in women may lower thyroid hormone levels in the blood and increase thyroid hormone requirements in women with hypothyroidism. Fluctuations in estrogen and other hormone levels during menstrual cycles can cause different moods and may be associated with depression. Particularly in women who have given birth, changes in hormone levels occur, and these hormonal irregularities can lead to depression.

An overactive thyroid gland causes the person to lose weight, and hormone levels affect the severity of weight loss. Increased weight loss is directly related to the severity of hyperthyroidism. Thyroid inflammation and high-dose thyroid hormone pills can also cause weight loss. Weight gain, on the other hand, is usually caused by an underactive thyroid gland. Weight gain may be seen more often in people with severe hypothyroidism. Weight gained in hypothyroidism is usually due to excess salt and water retention, and weight loss is expected with treatment. During thyroid treatment, creating a nutrition plan with your doctor and dietitian can help you achieve faster results in weight control.

If thyroid hormones are not under control, some health problems may occur during exercise. For example, hyperthyroidism caused by Graves' disease, an autoimmune disease, can cause the body to overheat excessively during exercise. As a result, feelings of anxiety or nervousness, redness, sweating and sleep problems may be experienced. Hashimoto's disease, an autoimmune disease that causes hypothyroidism, can cause the heart rate to slow due to an underactive thyroid, and may trigger palpitations, fatigue and a depressed mood. When thyroid treatments bring hormone levels back to normal, exercise is safe. Light exercises and activities such as yoga can help improve symptoms such as weight control issues, constipation and fatigue. Consult your doctor to determine the most suitable exercise plan for you.

Thyroid medications replace thyroid hormones that cannot be produced in sufficient amounts. Adequate thyroid hormone levels in the body are necessary to sustain physical and mental activity in a healthy way. Thyroid hormone is especially critical for growth and development in children. For this reason, thyroid medications recommended by your doctor should be taken regularly and check-ups should be ensured. Thyroid medications may cause unwanted side effects in some cases. Fatigue, heat intolerance, chest pain or discomfort, decreased urine output, difficulty swallowing and breathing, nervousness, menstrual irregularities, and itching and rash on the skin may be among these side effects. Thyroid disorders can also affect the functioning of other organs. For this reason, controlling diseases such as hypothyroidism, hyperthyroidism and nodules is critically important. If you think you may have thyroid problems, do not neglect to have your check-ups.