Hormone Health Hub: Expert Insights on Testing, Balance & Better Living — thyroid and inflammation

Reverse T3 (rT3) is one of the most misunderstood markers in thyroid testing. Often called the “hibernation hormone,” it is frequently claimed — without scientific basis — to block thyroid receptors and slow metabolism. In Part 2 of this series, Margaret Groves of ZRT Laboratory examines what the peer-reviewed literature actually says about rT3, when elevated levels are clinically meaningful, and how to interpret the T3/rT3 ratio in the context of a comprehensive thyroid assessment.

Thyroid symptoms can persist even when thyroxine (T4) levels appear normal — because thyroid function is profoundly affected by anything that disrupts the conversion of T4 to the active hormone T3 at the cellular level. In Part 1 of this two-part series, Margaret Groves of ZRT Laboratory explains the three deiodinase enzymes (D1, D2 and D3) that act as gatekeepers to intracellular thyroid hormone bioavailability, what affects circulating levels of T3 and reverse T3, and why selenium, iodine and inflammatory conditions all play a critical role.

Thyroid cancer is now among the top 10 most common cancers worldwide, with incidence rising by an average of 5.5% per year. But experts are divided: is this a genuine epidemic, or an epidemic of diagnosis driven by more sensitive imaging? This article reviews the evidence on both sides, explores the role of iodine deficiency, radiation exposure and environmental factors, and explains why thyroid awareness — and monitoring — matters year-round.

The thyroid gland is under constant threat from modern life — oestrogen dominance, chronic stress, iodine and selenium deficiency, heavy metal toxicity and xenoestrogen exposure all suppress its function. This article outlines 7 key action steps you can take to protect your thyroid, from hormone rebalancing and stress reduction to targeted nutritional support and testing.