Hypothyroidism is a condition where the thyroid gland, a small butterfly-shaped gland located in the neck, does not produce enough thyroid hormones. These hormones are very important because they control how the body uses energy—this process is known as metabolism.
When the thyroid is not making enough hormones, many of the body’s functions slow down, leading to a variety of symptoms.
One of the main causes of hypothyroidism is an autoimmune condition called Hashimoto’s thyroiditis. In this condition, the body’s own immune system mistakenly attacks the thyroid gland, causing damage and inflammation.
Over time, this damage makes it harder for the thyroid to produce enough hormones. Hashimoto’s thyroiditis is the leading cause of hypothyroidism in many parts of the world, especially in countries where people get enough iodine in their diet.
Iodine is a key mineral that the thyroid gland needs to make its hormones. In some parts of the world, like certain regions in Asia and Africa, people don’t get enough iodine from their food.
When this happens, the thyroid cannot produce enough hormones, leading to hypothyroidism. Even in countries where iodine is added to salt, some people may not get enough of it, which can still cause problems with thyroid function.
Sometimes, hypothyroidism is caused by treatments for hyperthyroidism, which is the opposite condition where the thyroid produces too much hormone. To treat hyperthyroidism, doctors sometimes use radioactive iodine therapy.
This treatment works by destroying part of the thyroid to reduce its hormone production. However, sometimes too many thyroid cells are destroyed, causing the thyroid to become underactive.
Surgery to remove part or all of the thyroid gland can also lead to hypothyroidism. This kind of surgery is often done to treat thyroid cancer, severe hyperthyroidism, or large thyroid nodules. When too much of the gland is removed, the body doesn’t have enough cells left to produce the hormones it needs.
Certain medications can also cause hypothyroidism. For example, lithium, which is often used to treat mood disorders, can interfere with thyroid function.
Another medication called amiodarone, which is used to control irregular heartbeats, can also affect the thyroid. People who take these medications usually need to have their thyroid levels checked regularly to make sure everything is normal.
In some cases, babies are born with hypothyroidism. This is called congenital hypothyroidism. It can happen if the baby is born without a thyroid gland or if the gland doesn’t work properly. In many countries, newborns are tested for thyroid problems right after birth. This early testing helps doctors catch the problem early so that it can be treated right away.
Radiation therapy to the neck or head, which is often used to treat certain cancers, can also damage the thyroid gland. This is why doctors closely monitor thyroid levels in people who have had this kind of treatment. Radiation can harm the thyroid cells, making it hard for the gland to produce enough hormones.
There are other types of inflammation that can affect the thyroid, known as thyroiditis. Besides Hashimoto’s, there are other kinds of thyroiditis that can also cause hypothyroidism.
For example, some women develop thyroid inflammation after giving birth—this is called postpartum thyroiditis. It can start with an overactive thyroid but then shift to an underactive thyroid, sometimes temporarily but sometimes permanently.
In rare cases, hypothyroidism can be caused by problems with the pituitary gland, which is located at the base of the brain. This gland releases a hormone called TSH (thyroid-stimulating hormone), which tells the thyroid to make its hormones.
If the pituitary gland is not working properly, it might not produce enough TSH, leading to low thyroid hormone levels. This type of hypothyroidism is called secondary hypothyroidism.
There is also a genetic factor to consider. Some people are more likely to develop hypothyroidism if it runs in their family. Research shows that certain genes can make someone more prone to thyroid problems. People with family members who have thyroid diseases are at higher risk.
In summary, hypothyroidism can have many causes. These include autoimmune diseases like Hashimoto’s thyroiditis, lack of iodine, treatments for an overactive thyroid, certain medications, conditions present from birth, radiation therapy, inflammation, issues with the pituitary gland, and genetic factors.
Understanding what causes hypothyroidism can help doctors diagnose it early and treat it effectively, improving health and quality of life for those who have it.
If you care about health, please read studies that vitamin D can help reduce inflammation, and vitamin K could lower your heart disease risk by a third.
For more health information, please see recent studies about new way to halt excessive inflammation, and results showing foods that could cause inflammation.
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