Iodine
Iodine is an essential trace element required for synthesizing thyroid hormones T3 and T4. Deficiency causes hypothyroidism, goiter, and, in pregnancy, impaired fetal brain development, and is still common globally. Excess iodine from supplements or medications such as amiodarone can trigger either hypothyroidism or hyperthyroidism and, in some people, autoimmune thyroiditis.
Optimal range: who says what
Institutions, researchers and practitioners draw the line in different places. Each position is listed with who holds it and, where a document states it, a link. How we verify ranges.
- Institution or study100-199 ug/LWHO adequacy range
- Lab reference interval52-109 μg/LWhat a lab report flags against. A lab interval is not an optimal target.
1 providers include this
Thyroid Function
Why Iodine matters
Required for thyroid hormone synthesis. Deficiency causes hypothyroidism and goiter. Excess can trigger autoimmune thyroid disease.
Which Providers Test Iodine?
Of the panels we itemize, only Function Health ($365/year, 160+ biomarkers) includes Iodine.
1 panel that includes it, cheapest first
| Provider | Annual Cost | Total Biomarkers | $/Biomarker |
|---|---|---|---|
 Function Health | $365 | 160+ | $2.28 |
$/Biomarker is annual cost divided by the panel's advertised biomarker count, not the price of this one test. We track 23 blood test providers (32 plans); 21 of those plans are itemized marker by marker. Compare all of them.
20 itemized panels do not include Iodine
Superpower · WHOOP Advanced Labs · Labcorp OnDemand · Life Extension Elite · Everlywell · Mito Health · InsideTracker · Marek Health Base · Marek Health Comprehensive · Marek Health Complete · Marek Health Executive · Blueprint · Empirical Health · Oura Health Panels · SiPhox Health · Hims Labs · Healthspan · Vitality Blueprint Standard · Vitality Blueprint Elite · Ultrahuman Blood Vision Annual
11 providers not itemized in our matrix
We have not itemized these marker by marker (some sell tests one at a time), so this page cannot say whether they offer Iodine. Check with them directly.
Life Extension Standard · Quest Health · Ultrahuman Blood Vision · Lifeforce · Hundred Health · Personalabs · Walk-In Lab · HealthLabs · WHOOP Specialized Panels · Marek Health Essential · Vitality Blueprint Upload
Experts discussing Iodine
Podcast episodes where clinicians and researchers cover this marker in depth. Curated by hand; an episode is listed only when the marker is a substantial topic, not a passing mention.
- How to Control Your Metabolism by Thyroid & Growth HormoneDisclosure: Huberman Lab has been sponsored by Function Health, which appears in our blood-test comparisons.
Frequently Asked Questions
What is the optimal range for Iodine?
Published position: 100-199 ug/L (WHO adequacy range). Lab reference interval: 52-109 μg/L. That is what a lab report flags against, not an optimal target.
Which blood test providers include Iodine?
1 of the 21 blood testing panels we itemize marker by marker include Iodine in their panels. This biomarker has limited availability.
Related: YouBoost rates lifestyle and supplement interventions by evidence.
Medical Disclaimer
This information is for educational purposes only and is not medical advice. Always consult with a qualified healthcare provider about your specific health needs.
Last reviewed Sep 23, 2026 · First published Sep 30, 2025