Hormone Health Hub: Expert Insights on Testing, Balance & Better Living — thyroid function testing

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.

Breast cancer rates have risen from 1 in 30 to 1 in 8 women over the past 30 years — yet the focus remains on treatment rather than prevention. Drawing on 35 years of clinical experience and infrared thermography, this article makes the case that environmental toxins, xenoestrogens, hormone imbalance and lifestyle factors may account for 91–93% of breast cancer risk. Prevention, not just awareness, is the real cure.

Millions of people struggle with weight gain, fatigue and low mood despite being told their thyroid test results are “normal.” The problem is that a standard TSH test alone cannot identify the full range of factors that suppress thyroid function — from oestrogen dominance and elevated cortisol to iodine deficiency, selenium deficiency, heavy metal toxicity and xenoestrogen burden. This article explains what those hidden saboteurs are and how targeted testing can help identify them.