What is the Difference Between Thyroid and Parathyroid Glands?

Most people know about the thyroid gland and its location inside the neck. However, when getting an endocrine evaluation from a medical professional, many people are surprised to learn they also have parathyroid glands.

Unlike the thyroid gland, of which there is just one, most people have four parathyroid glands. Despite the similarities in name and location, they serve different purposes, and each is associated with distinct disorders and health issues.

Knowing the differences between a thyroid vs. parathyroid gland is essential to understanding potential symptoms and receiving the right treatment.

Overview of the Endocrine System

The endocrine system is a critical part of the human body. It is primarily responsible for regulating many essential bodily functions by releasing hormones. It is a network of glands and organs spread across multiple areas instead of concentrated in a single location.

The key glands and organs in the endocrine system are located in the following body parts:

What is the Thyroid Gland?

The thyroid gland is the part of the endocrine system responsible for regulating metabolism, the production of energy, and overall growth.

Location and Anatomy

The thyroid gland is a small, butterfly-shaped gland found inside the neck. It is just under the skin in the front of your neck, under the Adam’s apple in men. You can feel it by applying gentle pressure on the correct part of the neck. The thyroid gland is made up of three parts: two lobes, forming the wings of its butterfly shape, and the isthmus in the center, connecting the lobes.

Functions

A healthy thyroid gland regulates hormone production and metabolism through the production of the thyroid hormones:

• Thyroxine (T4). Primarily regulates cell metabolic rate, which influences how the body uses energy.
• Triiodothyronine (T3). Regulates the metabolic rate, heart rate, and digestive functions. It also partially influences cell oxygen usage and heat generation rates and plays a role in brain functions, bone health, and muscle control.
• Calcitonin. Regulates calcium levels in the blood. It helps kidneys excrete calcium and promote its deposition into bones, keeping them strong and healthy.

Common Disorders

Due to the thyroid gland’s role in many critical bodily functions, malfunctions can affect the body in several unexpected ways. The most common thyroid disorders and their symptoms:

• Hyperthyroidism. This condition causes the thyroid gland to produce excessive amounts of hormones, causing metabolism imbalances. Common symptoms include a fast heartbeat, unexplained weight loss, increased appetite, heat intolerance, and anxiety attacks. The most common cause of hyperthyroidism is an autoimmune disorder known as Graves’ Disease.
• Hypothyroidism. This condition is characterized by opposite symptoms to hyperthyroidism and insufficient hormone production. Symptoms include fatigue, unexplained weight gain, sensitivity to the cold, dry skin, and constipation. Hashimoto’s Disease is the most common cause of hypothyroidism.
• Goiter. A goiter is a disorder characterized by an enlarged thyroid gland that causes the neck to appear swollen. Due to the pressure it applies to the neck, goiter often makes breathing and swallowing difficult. While various conditions can cause a goiter, the most common is iodine deficiency, which is often associated with hypothyroidism.
• Thyroid nodules. A thyroid nodule is a lump, either solid or filled with fluid, that grows from within the thyroid gland. While most are benign, some can become malignant and increase the risk of thyroid cancer. Depending on their size, they may also cause difficulties breathing or swallowing. Thyroid nodules must be detected through a physical examination or an imaging test like a neck ultrasound.
• Thyroid cancer. Thyroid cancer may develop when a thyroid nodule becomes malignant. The symptoms include neck pain, hoarse or altered voice, difficulties breathing and swallowing, or a persistent cough. In some cases, it may also resemble goiter and cause neck swelling.

What are Parathyroid Glands?

The parathyroid glands are another essential part of the endocrine system. Due to their differences in role, number, and location, it is important not to confuse thyroid vs. parathyroid glands.

Location and Anatomy

The primary difference between parathyroid and thyroid glands is their size and number. Most people have four parathyroid glands, each roughly the size of a pea, located on the rear surface of the thyroid gland.

Functions

The parathyroid glands’ primary function is regulating calcium levels in the blood. All produce a single hormone type, Parathyroid Hormone (PTH). When blood calcium levels are too low, PTH promotes calcium release from the bones and kidneys back into the blood. PTH also stimulates the intestines to produce calcitriol, improving calcium absorption.

Common Disorders

Parathyroid gland dysfunctions typically affect PTH hormone production, impacting calcium levels and causing various symptoms, including:

• Hyperparathyroidism. A benign parathyroid tumor typically causes this condition. It causes excessive production of PTH, which increases calcium release from the bones and kidneys. Symptoms include fatigue, weakness, abdominal pain, and excessive urination. Long-term hyperparathyroidism increases the risk of osteoporosis and kidney damage.
• Hypoparathyroidism. This condition is most commonly caused by genetic factors or autoimmune disorders. It results in an insufficient production of PTH, decreasing blood calcium levels. Symptoms include muscle cramps, fatigue, dry skin, and numb hands and feet. Severe cases can cause seizures, osteoporosis, and kidney failure.

Thyroid vs. Parathyroid Glands: Key Differences

Differentiating thyroid vs. parathyroid glands and the disorders associated with each can help you recognize the potential disorders and their symptoms. The differentiation also helps health professionals make accurate medical assessments, reducing the risk of misdiagnosis and ensuring you receive the proper treatment strategy.

Below is a table summarizing the key differences between each gland type:

Take Charge of Your Endocrine Health Today!

The team at Associated Endocrinologists specializes in diagnosing, treating, and managing all disorders related to the endocrine system. We can help you understand the differences between thyroid vs. parathyroid glands and their disorders.

If we detect any symptoms, our medical team is ready to build specialized care and treatment plans, including post-procedure care. Contact us today to learn more about our thyroid and parathyroid treatment options.