"Normal" TSH doesn't mean your thyroid is fine.
1 in 8 women will develop a thyroid condition in her lifetime.
Most doctors only test TSH. We test 8 markers including Reverse T3, antibodies, selenium, and iodine — because your thyroid is more than one number.
Why this matters for women
Thyroid disorders affect women 5-8 times more than men, yet most women receive only a TSH test. TSH can be "normal" while your Free T3 is low (causing fatigue, weight gain, and brain fog), your Reverse T3 is high (blocking thyroid hormone from working), or your antibodies are elevated (meaning Hashimoto's is silently destroying your thyroid). A complete thyroid panel changes everything. It's the difference between being told "your thyroid is fine" and discovering that your body isn't converting T4 to the active T3 form, or that autoimmune antibodies are attacking your thyroid years before your TSH becomes abnormal. We also test selenium and iodine — the two nutrients your thyroid needs most — because deficiency in either one can cause or worsen thyroid dysfunction.
Symptoms to watch for
What we test
TSH
Thyroid-stimulating hormone — the standard screening test. But TSH only tells your brain's request for thyroid hormone, not how much your body actually has available. "Normal" range is debated; many functional practitioners use 0.5-2.5 as optimal.
TPO & TG Antibodies
Thyroid peroxidase and thyroglobulin antibodies detect Hashimoto's thyroiditis — the most common cause of hypothyroidism in women. Antibodies can be elevated 7-10 years before TSH becomes abnormal.
Free T4
The unbound, available form of thyroxine — the storage hormone your thyroid produces. Low Free T4 with normal TSH can indicate early thyroid failure or poor production.
Total T3
Total triiodothyronine — measures all T3 in your blood (bound and unbound). Useful for assessing overall T3 production and identifying T4-to-T3 conversion problems.
Free T3
The most potent thyroid hormone and the form your cells actually use. Low Free T3 with normal TSH and T4 is extremely common in women and causes classic hypothyroid symptoms that get dismissed.
Reverse T3
An inactive form of T3 that blocks thyroid hormone receptors. Produced in excess during chronic stress, inflammation, dieting, or illness. High Reverse T3 explains why you feel hypothyroid despite "normal" labs.
Selenium
Essential for the enzyme that converts T4 to active T3. Selenium deficiency impairs thyroid function and is also critical for reducing thyroid antibodies in Hashimoto's.
Iodine
The building block of thyroid hormones — your thyroid literally can't make T4 or T3 without it. Iodine deficiency has been increasing due to dietary changes and is a reversible cause of hypothyroidism.
Who should consider this panel
- Women with fatigue, weight gain, or brain fog
- Anyone with a family history of thyroid disease
- Women who've been told their TSH is "normal" but still have symptoms
- Postpartum women (postpartum thyroiditis affects 5-10%)
- Women planning pregnancy (thyroid function directly affects fertility)
Cited sources
Subclinical Hypothyroidism: Prevalence, Health Impact, and Treatment Landscape
Yoo WS, Chung HK. Endocrinology and Metabolism, 2021.
Effect of selenium on thyroid autoimmunity and regulatory T cells in patients with Hashimoto's thyroiditis: A prospective randomized-controlled trial
Hu Y, et al. Clinical and Translational Science, 2021.
Laboratory Testing in Thyroid Conditions — Pitfalls and Clinical Utility
Soh SB, Aw TC. Annals of Laboratory Medicine, 2019.
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Your thyroid is more than one number. Get the complete panel.