What is the thyroid?

The thyroid gland is a small organ that’s located in the front of the neck, wrapped around the windpipe (trachea). It’s shaped like a butterfly, smaller in the middle with two wide wings that extend around the side of your throat. The thyroid is a gland. You have glands throughout your body, where they create and release substances that help your body do a specific thing. Your thyroid makes hormones that help control many vital functions of your body.

When your thyroid doesn’t work properly, it can impact your entire body. If your body makes too much thyroid hormone, you can develop a condition called hyperthyroidism. If your body makes too little thyroid hormone, it’s called hypothyroidism. Both conditions are serious and need to be treated by your healthcare provider.

What does the thyroid do?

Your thyroid has an important job to do within your body — releasing and controlling thyroid hormones that control metabolism. Metabolism is a process where the food you take into your body is transformed into energy. This energy is used throughout your entire body to keep many of your body’s systems working correctly. Think of your metabolism as a generator. It takes in raw energy and uses it to power something bigger.

The thyroid controls your metabolism with a few specific hormones — T4 (thyroxine, contains four iodide atoms) and T3 (triiodothyronine, contains three iodide atoms). These two hormones are created by the thyroid and they tell the body’s cells how much energy to use. When your thyroid works properly, it will maintain the right amount of hormones to keep your metabolism working at the right rate. As the hormones are used, the thyroid creates replacements.

This is all supervised by something called the pituitary gland. Located in the center of the skull, below your brain, the pituitary gland monitors and controls the amount of thyroid hormones in your bloodstream. When the pituitary gland senses a lack of thyroid hormones or a high level of hormones in your body, it will adjust the amounts with its own hormone. This hormone is called thyroid stimulating hormone (TSH). The TSH will be sent to the thyroid and it will tell the thyroid what needs to be done to get the body back to normal.

What is thyroid disease?

Thyroid disease is a general term for a medical condition that keeps your thyroid from making the right amount of hormones. Your thyroid typically makes hormones that keep your body functioning normally. When the thyroid makes too much thyroid hormone, your body uses energy too quickly. This is called hyperthyroidism. Using energy too quickly will do more than make you tired — it can make your heart beat faster, cause you to lose weight without trying and even make you feel nervous. On the flip-side of this, your thyroid can make too little thyroid hormone. This is called hypothyroidism. When you have too little thyroid hormone in your body, it can make you feel tired, you might gain weight and you may even be unable to tolerate cold temperatures.

These two main disorders can be caused by a variety of conditions. They can also be passed down through families (inherited).

Who is affected by thyroid disease?

Thyroid disease can affect anyone — men, women, infants, teenagers and the elderly. It can be present at birth (typically hypothyroidism) and it can develop as you age (often after menopause in women).

Thyroid disease is very common, with an estimated 20 million people in the Unites States having some type of thyroid disorder. A woman is about five to eight times more likely to be diagnosed with a thyroid condition than a man.

You may be at a higher risk of developing a thyroid disease if you:

  • Have a family history of thyroid disease.
  • Have a medical condition (these can include pernicious anemia, type 1 diabetes, primary adrenal insufficiency, lupus, rheumatoid arthritis, Sjögren’s syndrome and Turner syndrome).
  • Take a medication that’s high in iodine (amiodarone).
  • Are older than 60, especially in women.
  • Have had treatment for a past thyroid condition or cancer (thyroidectomy or radiation).

What causes thyroid disease?

The two main types of thyroid disease are hypothyroidism and hyperthyroidism. Both conditions can be caused by other diseases that impact the way the thyroid gland works.

Conditions that can cause hypothyroidism include:

  • Thyroiditis: This condition is an inflammation (swelling) of the thyroid gland. Thyroiditis can lower the amount of hormones your thyroid produces.
  • Hashimoto’s thyroiditis: A painless disease, Hashimoto’s thyroiditis is an autoimmune condition where the body’s cells attack and damage the thyroid. This is an inherited condition.
  • Postpartum thyroiditis: This condition occurs in 5% to 9% of women after childbirth. It’s usually a temporary condition.
  • Iodine deficiency: Iodine is used by the thyroid to produce hormones. An iodine deficiency is an issue that affects several million people around the world..
  • A non-functioning thyroid gland: Sometimes, the thyroid gland doesn’t work correctly from birth. This affects about 1 in 4,000 newborns. If left untreated, the child could have both physical and mental issues in the future. All newborns are given a screening blood test in the hospital to check their thyroid function.

Conditions that can cause hyperthyroidism include:

  • Graves’ disease: In this condition the entire thyroid gland might be overactive and produce too much hormone. This problem is also called diffuse toxic goiter (enlarged thyroid gland).
  • Nodules: Hyperthyroidism can be caused by nodules that are overactive within the thyroid. A single nodule is called toxic autonomously functioning thyroid nodule, while a gland with several nodules is called a toxic multi-nodular goiter.
  • Thyroiditis: This disorder can be either painful or not felt at all. In thyroiditis, the thyroid releases hormones that were stored there. This can last for a few weeks or months.
  • Excessive iodine: When you have too much iodine (the mineral that is used to make thyroid hormones) in your body, the thyroid makes more thyroid hormones than it needs. Excessive iodine can be found in some medications (amiodarone, a heart medication) and cough syrups.

Is there a higher risk of developing thyroid disease if I have diabetes?

If you have diabetes, you’re at a higher risk of developing a thyroid disease than people without diabetes. Type 1 diabetes is an autoimmune disorder. If you already have one autoimmune disorder, you are more likely to develop another one.

For people with type 2 diabetes, the risk is lower, but still there. If you have type 2 diabetes, you’re more likely to develop a thyroid disease later in life.

Regular testing is recommended to check for thyroid issues. Those with type 1 diabetes may be tested more often — immediately after diagnosis and then every year or so — than people with type 2 diabetes. There isn’t a regular schedule for testing if you have type 2 diabetes, however your healthcare provider may suggest a schedule for testing over time.

If you have diabetes and get a positive thyroid test, there are a few things to you can do to help feel the best possible. These tips include:

  • Getting enough sleep.
  • Exercising regularly.
  • Watching your diet.
  • Taking all of your medications as directed.
  • Getting tested regularly as directed by your healthcare provider.

What common symptoms can happen with thyroid disease?

There are a variety of symptoms you could experience if you have a thyroid disease. Unfortunately, symptoms of a thyroid condition are often very similar to the signs of other medical conditions and stages of life. This can make it difficult to know if your symptoms are related to a thyroid issue or something else entirely.

For the most part, the symptoms of thyroid disease can be divided into two groups — those related to having too much thyroid hormone (hyperthyroidism) and those related to having too little thyroid hormone (hypothyroidism).

Symptoms of an overactive thyroid (hyperthyroidism) can include:

  • Experiencing anxiety, irritability and nervousness.
  • Having trouble sleeping.
  • Losing weight.
  • Having an enlarged thyroid gland or a goiter.
  • Having muscle weakness and tremors.
  • Experiencing irregular menstrual periods or having your menstrual cycle stop.
  • Feeling sensitive to heat.
  • Having vision problems or eye irritation.

Symptoms of an underactive thyroid (hypothyroidism) can include:

  • Feeling tired (fatigue).
  • Gaining weight.
  • Experiencing forgetfulness.
  • Having frequent and heavy menstrual periods.
  • Having dry and coarse hair.
  • Having a hoarse voice.
  • Experiencing an intolerance to cold temperatures.

Can thyroid issues make me lose my hair?

Hair loss is a symptom of thyroid disease, particularly hypothyroidism. If you start to experience hair loss and are concerned about it, talk to your healthcare provider.

Can thyroid issues cause seizures?

In most cases, thyroid issues don’t cause seizures. However, if you have a very severe cases of hypothyroidism that hasn’t been diagnosed or treated, your risk of developing low serum sodium goes up. This could lead to seizures.

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