Why do I “almost” have an underactive thyroid?

Ask the doctor

Published: March, 2018

Image: © magicmine/Getty Images

Q. My doctor said I "almost" have an underactive thyroid, which puzzled me. Then she said I might benefit from treatment, which puzzled me more. How can you "almost" have a disease, and how can treatment be useful if you don't have the disease?

A. I can see how that might have been confusing. In fairness, it's a confusing situation, even for doctors. Let's take this in two parts. First, what's an "underactive thyroid"? The thyroid gland in our neck makes a hormone, called thyroid hormone, that travels throughout the body and affects every cell. If it is making the right amount of the hormone — if the blood levels are normal — then there's no problem. If it's making too much (an overactive thyroid), or if it's making too little (an underactive thyroid), those are problems that require treatment.

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