Parathyroid gland
The parathyroid glands are four small endocrine glands located in the neck, behind the thyroid. Their primary function is to regulate calcium levels in the body, which is crucial for the proper functioning of the nervous, muscular, and skeletal systems. When these glands malfunction, it can lead to conditions such as hyperparathyroidism, characterized by excessive calcium in the blood, or hypoparathyroidism, where there is insufficient calcium. The glands achieve calcium regulation through the release of parathyroid hormone (PTH), which influences calcium release from bones, kidney reabsorption, and dietary absorption.
Hyperparathyroidism is often caused by benign tumors on the glands, known as parathyroid adenomas, which can lead to symptoms like fatigue, mood changes, and muscle weakness. Conversely, hypoparathyroidism can result in low calcium levels, affecting nerves and muscles. Treatment for glandular issues may involve surgery to remove affected glands or supplementation for hormone deficiencies. A healthy diet rich in calcium and vitamin D can help maintain parathyroid health, highlighting the importance of nutrition in supporting bodily functions.
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Parathyroid gland
A parathyroid gland is one of four small glands in the endocrine system. These glands are located in the neck, just behind the thyroid gland. Their sole purpose is to control the level of calcium in the body, which helps ensure the healthy function of the nervous, muscular, and skeletal systems. If something happens to make one or more of the glands malfunction, the result could be too much or too little calcium in the body. This could negatively affect a person's health. However, doctors can usually correct the problem with surgery or medications.
Background
The parathyroid glands are part of the endocrine system, which releases chemical substances called hormones that help regulate a variety of functions in the body. These functions include growth, metabolism, and the development and activities of the reproductive system. Various factors can cause any of these glands to release too much or too little hormone, and this imbalance can cause a number of illnesses.
Although the word thyroid is in their name, the parathyroid glands are not related to the thyroid except for the fact that they are all part of the endocrine system. There are four parathyroid glands, and each is somewhere between the size of a grain of rice and a pea when healthy. They are mustard yellow in color and located behind the thyroid in the neck.
Overview
The only function of the parathyroid glands is to regulate the amount of calcium in the body. Calcium serves several crucial purposes in the body, and it is essential to health. It is the only element or mineral in the body that has a system dedicated to its regulation. Calcium is best known for helping to strengthen bones. The bones serve as banks for the body's calcium supply. The body constantly deposits and withdraws calcium from the bones to help keep the level of calcium in the blood at the right amount.
Maintaining these levels is important for the function of the nervous system. The body uses calcium to conduct the electrical impulses throughout this system. When the parathyroid glands are not producing the right amount of parathyroid hormone (PTH), nerves cannot function properly.
In addition to conducting the electrical impulses that help nerves function, calcium helps muscles contract. When the calcium levels in the blood are not correct, muscle function is impaired. This can have consequences ranging from muscle weakness to heart problems, since the heart is a muscle.
The parathyroid glands are constantly monitoring the body's blood calcium levels. If the level dips, the glands manufacture PTH, which works to increase the amount of calcium in the bloodstream. The PTH does this in three ways: by releasing calcium from the bones, by preventing the kidneys from excreting as much calcium, and by helping the body to absorb more calcium from food. Once the correct level is reached again, the glands stop making PTH.
Sometimes, a malfunction in one or more of the parathyroid glands causes the release of too much PTH, a condition known as hyperparathyroidism. When this happens, the blood calcium level becomes too high. This is known as hypercalcemia. Most of the time, hyperparathyroidism is caused by a tumor on one or more of the parathyroid glands. This condition is known as parathyroid adenoma. These tumors are usually benign, or noncancerous, and only one gland is affected in more than 90 percent of the cases. It is rare for two or more glands to develop tumors at the same time. The tendency to develop these tumors can be hereditary, or it can occur for unknown reasons. The odds of developing a parathyroid tumor are about one in one hundred for people of all ages and about one in fifty for women over the age of fifty.
The tumors can swell the gland to the size of a walnut. In some cases, the gland swells on its own, without a tumor present. The affected gland will release excess PTH and drastically increase the amount of calcium circulating in the blood stream.
Excess levels of calcium in the blood is usually noticed first by its effects on the nervous system. The person will often experience mood changes, develop depression, and become weak and fatigued. When the levels begin to affect the muscular system, the person may develop muscular weakness and cramps. The excess calcium can also collect in the kidneys, which help the body excrete waste, including excess hormones and minerals. When this happens, kidney stones—small, hard pellets that form inside the kidney—can develop, blocking the flow of urine and causing pain. Since the excess levels of PTH continually led to withdrawals of calcium from the bones, the person will also develop osteoporosis, a condition where the bones are weakened and easily broken.
The most common result of a parathyroid gland malfunction is hyperparathyroidism and the presence of too much calcium. Another condition, hypoparathyroidism, is much rarer. In this condition, too little PTH is released and too little calcium flows into the bloodstream. This results in an imbalance between the blood levels of calcium and phosphorus. Low calcium and high phosphorus levels cause problems with nerve endings, bones, muscles, and skin.
In most cases where a parathyroid gland swells or develops a tumor, the cure is to remove the gland. One-half of a single parathyroid gland is sufficient to regulate the body's calcium levels, so removing a gland does not create any lasting problem. Cases where the glandular malfunction results in hypoparathyroidism, or the release of too little PTH, are usually treated by the administration of vitamin D and oral calcium supplements.
People can help protect the parathyroid glands by eating a healthy diet. For example, they should try to eat more foods that contain calcium, such as dairy products and green leafy vegetables like kale and spinach. Adequate levels of vitamin D will also help promote healthy function of the parathyroid glands. Foods with good levels of vitamin D include fortified milk, orange juice, cereal, fish, beef liver, and mushrooms.
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