Testing For Thyroid Function, Explained By An Endocrinologist

In order to screen for thyroid dysfunction, you’ll likely take at least one blood test looking at thyroid-stimulating hormone, or TSH. This hormone is released by the pituitary gland, according to Sonal Chaudhry, MD, Endocrinologist at NYU Langone Health.

What do test results for thyroid function mean?

Here are some examples of what your test results may mean:

• If your TSH is high and your thyroid hormone levels are low, you could have primary hypothyroidism. This means that your thyroid isn’t making enough thyroid hormone.

• If your TSH is low and your thyroid hormone levels are high, then you could have hyperthyroidism. This means that your body is making too much thyroid hormone. 

• If your TSH and your thyroid hormone levels are low, you could have central hypothyroidism. This means that your pituitary gland isn’t secreting enough hormones to support the functioning of your thyroid gland.

“If you have symptoms that are suggestive of thyroid dysfunction, it’s important to be tested for it,” says Dr. Chaudhry. “It’s very easy to make the diagnosis, and it’s very easy to treat if you have a problem.”

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Written by:

Marisa Taylor Karas

Marisa Taylor Karas is a freelance journalist based in Brooklyn who has covered health, gender, and technology for 15 years. She previously worked at The Wall Street Journal, The Guardian, and Al Jazeera America, among other publications, and also served as managing editor of the Mellon Foundation in New York City.

Reviewed by:

Mera Goodman, MD, FAAP

Dr. Mera Goodman is a board-certified pediatrician. Prior to medicine, she worked as a management consultant.

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