Hormone Health Hub: Expert Insights on Testing, Balance & Better Living — iodine and fertility

Nearly 2 billion people worldwide are iodine deficient — and many don't know it. Discover why iodine is critical for thyroid health, who is most at risk, and how a simple at-home urine test can reveal your levels.

Most people associate iodine exclusively with thyroid health — but this essential mineral plays a far broader role in the body. From breast tissue and ovarian function to fetal brain development and endometrial health, iodine is active in virtually every organ system. Deficiency is more widespread than commonly recognised, and standard thyroid blood tests cannot reliably detect it. This guide explores the extrathyroidal roles of iodine, the difference between iodide and molecular iodine, the controversy around dosing, and why testing urinary iodine is the most accurate way to assess your status.

Iodine is an essential trace element required for thyroid hormone production, yet many people are unknowingly deficient. While iodised salt and seafood are well-known sources, dairy products, eggs, and seaweed also contribute significantly to daily intake. Changing dietary habits — including reduced milk consumption and the replacement of iodine with bromine in bread production — are quietly lowering iodine intake across the population. This article explains where dietary iodine comes from, why the body needs it, how it is absorbed and excreted, and how at-home urine testing can confirm whether your intake is adequate.

If you are experiencing infertility issues, understanding which hormones to test — and why — is the essential first step. Dr. Alison McAllister of ZRT Laboratory explains the full fertility hormone profile: from LH and FSH as indicators of ovarian reserve, to estradiol, progesterone and testosterone for ovulation health, adrenal hormones cortisol and DHEA-S, thyroid markers including TPO antibodies, and the often-overlooked role of vitamin D in fertility and PCOS.

Iodine deficiency is more common than many realise. This guide walks through how to assess iodine status using dietary recall, symptom profiling, and a three-part laboratory panel — including thyroid function, thyroglobulin, and urinary iodine and bromine testing.