Do you know about that little butterfly on your neck? Let's talk about the thyroid gland!

Have you ever wondered about the tiny, butterfly-shaped organ just under the skin at the front of your neck? That's the thyroid gland. It's an amazing, yet essential part of our body. Simply put, this little guy controls many of the most important functions in our body.

What is the thyroid gland? And what is the endocrine system?

Okay, let's first understand what this thyroid gland is. I've said before, it's a small butterfly-shaped gland . To be precise, it's located in the front of your neck, just below your windpipe. This is part of our endocrine system . Now you're asking, "What is the endocrine system, doctor?" Imagine, we have a bunch of little factories in our bodies. These factories make special chemicals called hormones . The network of those factories is what we call the endocrine system. The hormones made by these glands go directly into the blood, travel throughout the body, and carry messages to various organs, skin, and muscles. They're like messengers in our bodies. They tell our bodies what to do and when to do it. Here are some other glands that are part of our endocrine system:

• Hypothalamus
• Pituitary gland
• Parathyroid glands
• Adrenal glands
• Pineal gland
• Pancreas
• Ovaries (in women)
• Testes (male)

The main function of the thyroid gland is to control our metabolic rate . "Metabolism" simply means the process by which the food we eat is converted into energy. Every cell in our body needs energy to function. The thyroid controls how quickly that energy is produced and used.

Just think, if your thyroid isn't working properly, it can affect your entire body. So it's very important to be aware of this.

What's going on with my thyroid?

As an endocrine gland, the thyroid produces and secretes several hormones. These are:

• Thyroxine (T4):This is the main hormone produced by the thyroid. However, it does not directly affect metabolism. After T4 enters the blood, it is converted into T3 through a process called `deiodination`.
• Triiodothyronine (T3): The thyroid produces less T3 than T4. However, it is the T3 hormone that has the greatest impact on metabolism .
• Reverse triiodothyronine (RT3): This is produced in very small amounts. RT3 reverses the action of T3.
• Calcitonin: This hormone helps regulate the amount of calcium in our blood.

To make these thyroid hormones, the thyroid gland needs an element called iodine . We get iodine from food (especially iodized salt) and water. The thyroid gland takes this iodine and converts it into thyroid hormones. Think about it, if your body has too much or too little iodine, it can affect the amount of thyroid hormones it produces. Thyroid hormones affect things like:

• How our bodies use energy ( metabolism )
• Heart rate
• Breathing
• Digestion
• Body temperature
• Brain development
• Mental activity
• Skin and bone maintenance
• Fertility

What other organs and glands are associated with the thyroid gland?

Our endocrine system is a very complex network. Many glands and hormones work on signals from other glands and hormones. Also, some hormones can suppress other hormones. There is also a very complex system to control the level of thyroid hormones in our body. First, the hypothalamus, which is a part of our brain, releases a hormone called thyroid-releasing hormone (TRH). This TRH goes to stimulate a part of our pituitary gland , which releases thyroid-stimulating hormone (TSH). This TSH then stimulates the follicular cells in the thyroid gland to produce T4 and T3 hormones. However, for this to work, there must be enough iodine in the body. The thyroid gland and its hormones affect almost every system in our body. To give a few examples:

• Cardiovascular system: The thyroid helps regulate things like how much blood our heart pumps (cardiac output), heart rate, and the strength of our heart's contractions.
• Nervous system:When the thyroid is not working properly, symptoms related to the nervous system can occur. For example, numbness , tingling , pain, and burning sensations in some areas. Also, if the thyroid function is reduced (hypothyroidism), depression can occur, and if it is increased (hyperthyroidism), anxiety can occur.
• Digestive system: The thyroid is also involved in the way the food we eat moves through the digestive tract (gastrointestinal motility).
• Reproductive system: If there is a problem with the thyroid, women's menstrual cycles may become irregular and fertility problems may occur.

Can a person live without a thyroid gland?

Yes, you can. However, you will need to take hormone replacement medication for the rest of your life to stay healthy and avoid side effects. Surgery to remove the thyroid gland, called a thyroidectomy , is a common surgery for some thyroid conditions.

Where is the thyroid gland located? What are its parts? How big is it?

As I mentioned before, the thyroid gland is located in the front of your neck, just above your windpipe (trachea) . It’s shaped like a butterfly – with a small one in the middle and two large wings that spread out on either side. A healthy thyroid gland is usually not visible (it doesn’t look like a lump in your neck), and you can’t feel it if you touch it with your finger at the front of your neck. The thyroid gland has two main parts: the two lobes (lobes) and the middle part that connects these two lobes (thyroid isthmus) . This is made up of thyroid follicle cells (thyrocytes), which make and store thyroid hormones (mainly T3 and T4), and C-cells , which make the hormone calcitonin. The thyroid gland is about 2 inches long . A healthy thyroid gland is usually not visible and protrudes from the neck. However, some medical conditions can cause the thyroid to become enlarged. This is called a goiter . Some people also call it a "goiter." If you have a goiter, you may experience symptoms like these:

• A swelling in the front of the neck, just below the collarbone.
• Feeling of tightness in the throat.
• Voice changes, for example, hoarseness.

What diseases and conditions affect the thyroid gland?

There are several types of thyroid disease. These are very common. It is estimated that about 20 million people in the United States alone suffer from some form of thyroid disorder. Women are five to eight times more likely to develop thyroid disease than men. Thyroid disease is mainly divided into two types: primary and secondary .

• In primary thyroid disease, the disease begins in the thyroid gland itself.
• In secondary thyroid disease , the disease starts in the pituitary gland. For example, if a nodule develops on your thyroid and causes it to produce too much thyroid hormone, it is primary hyperthyroidism. However, if a tumor develops on your pituitary gland and causes it to produce too much TSH, which stimulates the thyroid to produce too much hormone, it is secondary hyperthyroidism.

There are four main conditions that affect the thyroid gland:

• Hypothyroidism (underactive thyroid gland)
• Hyperthyroidism ( overactive thyroid gland)
• Goiter ( enlarged thyroid gland/goiter)
• Thyroid cancer

Hypothyroidism - when the thyroid gland is underactive

This happens when your thyroid gland doesn't make enough thyroid hormones . This slows down some of your metabolism. This is also a common condition. There are treatments for it. There are several causes of hypothyroidism:

• Hashimoto's disease: This is an `autoimmune` disease. This means that our own immune system attacks the thyroid.
• Thyroiditis: Inflammation of the thyroid gland.
• Iodine deficiency.
• Congenital thyroid dysfunction.
• Overuse of medications for hyperthyroidism.
• Surgical removal of the thyroid gland.

Hyperthyroidism - when the thyroid gland is overactive

This happens when your thyroid gland makes and releases too much thyroid hormone . This speeds up some of your metabolism. There are treatments for this too. There are several causes of hyperthyroidism:

• Graves' disease: This is also an autoimmune condition.
• Thyroid nodules.
• Thyroiditis.
• Postpartum thyroiditis: Inflammation of the thyroid gland that occurs after childbirth.
• Excess iodine in the blood, either from food or medication.
• Overuse of medication for hypothyroidism.
• A non-cancerous (benign) tumor of the pituitary gland.

Goiter - enlargement of the thyroid

Goiter is an enlargement of the thyroid gland. This is also relatively common. The causes vary depending on the type of goiter:

• Simple goiters: These develop when the thyroid gland does not produce enough hormones for the body. The thyroid then tries to enlarge to compensate for the deficiency.
• Endemic goiters: These develop in people who do not get enough iodine from their diet. In Sri Lanka, this condition is now rare because we add iodine to the salt we eat.
• Sporadic goiters: Most often, there is no clear cause for these. Sometimes, they can also be caused by certain medications, such as lithium.

Thyroid cancer

This is a cancer that starts in the thyroid tissue. Treatment for most thyroid cancers is very successful. Don't worry, it can be cured in most cases. Thyroid cancer is classified according to the type of cell from which the cancer develops:

• Papillary: About 80% of thyroid cancers are of this type.
• Follicular: About 15% are of this type.
• Medullary: About 2%. This may also be due to a gene mutation.
• Anaplastic: About 2%. This is a bit more severe, but not common.

What are the early warning signs of thyroid problems?

Different thyroid diseases have different symptoms. However, since the thyroid plays a major role in many things in our body, such as heart rate, metabolism, and temperature control, you should be aware of these symptoms:

• Decreased or increased heart rate.
• Becoming thin or fat for no reason.
• Difficulty tolerating cold or heat.
• Depression or anxiety.
• Irregular menstrual cycles in women.

If you have one or more of these symptoms, it's best to see a doctor and get a blood test to check your thyroid function.

What are the common tests done to check thyroid health?

The first and most important test to check your thyroid health is a blood test to check your TSH (Thyroid-Stimulating Hormone) level. This can give you an idea of ​​both hypothyroidism and hyperthyroidism. The normal range for a TSH blood test is between 0.5 and 5.0 mIU/L (milli-international units per liter). However, this can vary slightly from lab to lab, depending on factors like your age and pregnancy status. So compare it to the values ​​in your report. Your doctor may also check your T4 and T3 (thyroid hormone) levels in your blood. If your test results are abnormal, your doctor may order a thyroid scan.You may be asked to do either a CT scan (which uses a small, safe radioactive substance to take pictures of the thyroid) or a thyroid ultrasound .

How are thyroid diseases treated?

There are several treatments for thyroid disease. It depends on what the disease is and how severe it is. There are three main treatment options:

• Medication
• Surgery
• Radiation therapy and chemotherapy

Medication

Medications for thyroid diseases:

• Antithyroid medications: These medications stop the thyroid from making hormones. They are given for hyperthyroidism.
• Beta-blockers: These medications control the symptoms of hyperthyroidism (such as a fast heartbeat), but do not cure the thyroid disease itself.
• Radioactive iodine: This medication damages thyroid cells, eventually destroying the thyroid gland. It is a treatment for hyperthyroidism and thyroid cancer.
• Thyroid hormone medications: These are synthetic thyroid hormones. They are given to treat hypothyroidism. People who have had a thyroidectomy or whose thyroid is not working because of radioactive iodine will have to take these medications for the rest of their lives.

Surgery

The main surgical procedure for thyroid disease is a thyroidectomy . This involves surgically removing the entire thyroid gland. A thyroidectomy is a treatment option for thyroid disease and is the first-line treatment for thyroid cancer. Another surgical option is a lobectomy , which removes only part of the thyroid.

Radiation therapy and chemotherapy

These are treatment options for thyroid cancer. Both of these treatments kill cancer cells and stop them from growing. However, most thyroid cancers do not require radiation therapy or chemotherapy.

What are the risk factors for developing thyroid disease?

Thyroid disease is common and can affect people of any age. However, certain factors may increase your risk of developing thyroid disease:

• Having a family history of thyroid disease (hereditary link).
• Having an autoimmune disease, such as type 1 diabetes, rheumatoid arthritis, or lupus.
• Taking a medicine that contains too much iodine.
• Being over 60 years old, especially if you are a woman.

How can I keep my thyroid healthy?

What you need to keep your thyroid healthyThe main way is to get enough iodine from the foods you eat. The thyroid needs iodine to make thyroid hormones. The good news is that most people get enough iodine from iodized salt and foods with added iodine. Other foods that contain iodine:

• Cheese
• Cow's milk
• Eggs
• Yogurt
• Sea fish
• Shellfish, such as crabs and shrimp
• Seaweed
• Soy milk
• Soy sauce

However, taking too much iodine is not good and can also cause problems. If you have any questions or concerns about your thyroid health, don't hesitate to talk to your doctor.

When should I talk to a doctor about my thyroid?

If you're experiencing symptoms of thyroid disease, such as changes in your weight, heart rate, or temperature sensitivity , see your doctor. He or she can do a simple blood test to see if your thyroid is causing your symptoms.

Finally, things to remember (Take-Home Message)

Your thyroid is a very important gland in your endocrine system. It affects many things in your body. Thyroid disease is very common, and it can be treated and cured to a large extent.

If you have symptoms related to thyroid disease, or if you want to know if you have any risk factors for developing thyroid disease, don't be afraid or hesitate to talk to your doctor. They are here to help you. Taking care of your health is the most important thing!

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Thyroid, thyroid gland, hormones, hypothyroidism, hyperthyroidism, goiter, thyroid cancer