Must-Know Facts About Your Thyroid

When this little gland is out of whack, it can cause a range of issues, from weight gain to insomnia.

doctor examining a woman's neck for thyroid enlargement in an exam room, nurse in the background

Updated on July 18, 2023

The small, butterfly-shaped endocrine gland at the bottom of your throat, otherwise known as the thyroid, is responsible for much of your body’s function, starting with your metabolism. When your thyroid doesn’t work properly, it can cause symptoms ranging from dry skin to weight gain, from insomnia to depression. Given the wide variety of these symptoms and their overlap with those of other conditions, it can be difficult to diagnose thyroid issues.

There are several different kinds of thyroid disease, but hypothyroidism and hyperthyroidism are the two most common. Hypothyroidism means you have an underactive thyroid gland that can’t produce enough hormones to keep the body running properly, while hyperthyroidism means you have an overactive thyroid that produces too much thyroid hormone, sending certain bodily functions into overdrive.

Here are some key things to know about your thyroid and about thyroid disease:

Thyroid disease is more common than you think

About 1 in 100 Americans over the age of 12 has hyperthyroidism, while approximately 5 in 100 have hypothyroidism. Yet 60 percent of those affected may not even know they have a thyroid condition. If thyroid disease isn’t diagnosed, it can lead to more serious problems, such as cardiovascular disease, osteoporosis, and problems getting or staying pregnant. 

All symptoms are not the same

Hypothyroidism is by far the most common thyroid disorder among adults, and women and people over 60 have a higher risk. Its symptoms are different than those of hyperthyroidism, even though they involve the same endocrine gland.

“Patients become fatigued to the point of sleeping a lot,” says Khalil Afsh, MD, an internist in Jacksonville, Florida. Weight gain is another common issue. As the body’s metabolic function slows down, other symptoms such as getting cold more easily, dry skin, depression, or constipation may occur.

Hyperthyroidism symptoms are typically very different, and sometimes they come on quickly. 

“Something abrupt happens in the gland, releasing a lot of the hormone into the bloodstream, which is a reflection of a high metabolic rate,” says Dr. Afsh. “Patients come in with unusual irritability and heart palpitations, insomnia, losing weight, diarrhea.”

The causes of thyroid disease vary

Hashimoto’s disease, a type of inflammation of the thyroid gland, is the most common cause of hypothyroidism in the United States. This autoimmune disorder attacks the thyroid specifically, causing inflammation and impairing your body’s ability to produce enough thyroid hormone. Less common causes include thyroid surgery or radiation treatments (for example, to treat thyroid cancer), iodine deficiency, another type of inflammation called thyroiditis, and pituitary or hypothalamus disorders. Some people are born with it; this is called congenital hypothyroidism.

Graves’ disease is the most common cause of hyperthyroidism. It’s an autoimmune disorder that develops when antibodies called thyroid-stimulating immunoglobulin (TSI) attach to thyroid cells and stimulate them to produce too much thyroid hormone. Hyperthyroidism can also be caused by benign (non-cancerous) thyroid tumors, consuming too much iodine (in either food or supplements), or by taking too much thyroid hormone medication.

Thyroid conditions are treatable

While thyroid conditions are normally life-long, medical treatments and certain lifestyle changes can help you manage the symptoms so that they don’t develop into something more serious.

If you have hypothyroidism, your healthcare provider (HCP) will likely recommend medication to replace your low thyroid hormones, such as levothyroxine. It’s the same as one of the hormones that your thyroid makes, and taking it as a capsule or liquid will help ensure that you have enough energy to fuel your body’s important functions. Your HCP should test your thyroid levels regularly to see if tweaks need to be made to your dose. 

If you have hyperthyroidism on the other hand, your HCP may try a wider variety of treatment options. Medications like beta-blockers can alleviate symptoms and antithyroid drugs can help stop your thyroid from overproducing certain hormones. Less often, HCPs suggest surgery to remove part of your thyroid so that your levels can return to normal.

In both cases, it may be helpful to speak to a registered dietician or nutritionist to help you monitor your iodine intake. Iodine from food and supplements can make thyroid symptoms worse in some people. 

See your provider if you have symptoms

Who doesn’t feel fatigued or irritable at times, or suffer from a bout of constipation or diarrhea? This is where diagnosis can become tricky. “All these symptoms can be so many different things,” says Afsh. “People don't even think of the thyroid as a potential cause.” When you do experience symptoms, “see your doctor right away,” says Afsh. “You should always be reminding your physician to check your thyroid.”

This is especially true if you’re pregnant or trying to conceive. Too little or too much thyroid hormone can cause complications that put your health and the health of your baby at risk. 

Even if you’re not sure that your symptoms point to a thyroid problem, speak to your HCP and get tested. A simple blood test can help you get the relief you need.

Article sources open article sources

National Institute of Diabetes and Digestive and Kidney Disorders. Hypothyroidism (Underactive Thyroid). Page last reviewed March 2021.
National Institute of Diabetes and Digestive and Kidney Disorders. Hyperthyroidism (Overactive Thyroid). Page last reviewed August 2021.
Weill Cornell Medicine. Understanding Thyroid Problems & Disease. January 25, 2022.
National Institute of Diabetes and Digestive and Kidney Disorders. Hashimoto’s Disease. Page last reviewed June 2021.
National Institute of Diabetes and Digestive and Kidney Disorders. Graves’ Disease. Page last reviewed November 2021.
National Institute of Diabetes and Digestive and Kidney Disorders. Thyroid Disease & Pregnancy. Page last reviewed December 2017.

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