A normal TSH can still miss Hashimoto's

You're tired, cold when no one else is, and your hair is thinner than it used to be. Someone checked your thyroid. The result was one number, TSH, and it was normal. Case closed, apparently.

Maybe not. TSH is where most thyroid workups start and stop, and it can stay inside the range for years while Hashimoto's is already underway.

Hashimoto's is common, and it starts quietly

Hashimoto's thyroiditis is, in the American Thyroid Association's words, the most common cause of hypothyroidism in the United States. The NIDDK describes it as an autoimmune disorder that can cause hypothyroidism: the immune system targets the thyroid, and over time the thyroid makes less hormone.

That "over time" is the problem. The ATA says Hashimoto's often progresses very slowly over many years, and it describes a stage where thyroid antibodies are high while thyroid hormone levels are still normal. The NIDDK adds that it's 4 to 10 times more common in women than men and most often develops in women ages 30 to 50, the same years perimenopause often begins.

Why TSH alone can miss it

TSH stands for thyroid-stimulating hormone, and your thyroid doesn't make it. The ATA explains that it's made in the pituitary gland located at the base of the brain. TSH is the pituitary asking the thyroid for more hormone. It measures the request, not the response, and it says nothing about why a thyroid might be struggling.

While a thyroid under autoimmune attack is still keeping up, TSH can look fine. Antibodies are the test that shows the cause, and they're rarely part of a standard hormone panel. Most people who come to us have never had them checked.

The most common symptoms of Hashimoto's

These are the symptoms our providers see most often. Most come from the underactive thyroid Hashimoto's eventually causes, and early on many people have mild symptoms or none.

• General and metabolic: fatigue and low energy, weight gain or trouble losing weight, feeling cold when others don't, a puffy face, especially around the eyes, and a hoarse voice.
• Skin, hair and nails: dry, rough skin, thinning hair or hair loss, including the outer third of the eyebrows, and brittle nails.
• Muscles and joints: muscle aches, stiffness or weakness, joint pain and stiffness, and cramps.
• Brain and mood: brain fog, poor concentration and memory problems, low mood or depression, anxiety, which is more common in early or fluctuating phases, and slowed reflexes.
• Digestion: constipation and bloating.
• Heart: a slow heart rate and higher LDL cholesterol.
• Reproductive: heavy or irregular periods, lower libido, and fertility problems or repeated miscarriage.
• The thyroid itself: a goiter, an enlarged thyroid that can feel like fullness in the neck or make swallowing harder.

Many of these appear on the NIDDK's list of Hashimoto's symptoms, and most of them have other possible causes too. A list like this is a reason to test, not a diagnosis.

What a full thyroid panel checks

Our thyroid panel looks at 5 markers together. TSH is the pituitary's signal. Free T4 is the main thyroid hormone in the form that, as the ATA puts it, can enter and affect body tissues. Free T3 is the more active form. Reverse T3 is an inactive form, and our providers read it next to free T3. And TPO and thyroglobulin antibodies, which the ATA notes point to Hashimoto's thyroiditis in a person with hypothyroidism.

Read together, those 5 show how the thyroid is working and why. Read one at a time, they can each look fine.

Check what your last thyroid test covered

Find your most recent thyroid result and look at the test names. Was it TSH alone? Were free T4, free T3 and reverse T3 included? Were TPO or thyroglobulin antibodies checked?

Now compare it with the symptom list above. If several fit and your workup stopped at TSH, you have a good reason to ask for more.

Thyroid care at Elevate

Thyroid is part of the whole hormone picture, so we treat it that way. Our thyroid panel covers all 5 markers, results are read next to your symptoms in a one-on-one consult with a provider, and thyroid markers are part of our women's, men's and weight loss panels too.

A normal TSH is one answer. The rest of the panel tells you whether it's the whole one.