Hormone Health Hub: Expert Insights on Testing, Balance & Better Living — Hormone Replacement Therapy

Hot flashes, mood instability, brain fog and memory changes during perimenopause are not “all in your head” — but they are very much in your brain. In this in-depth clinical article, Dr. Kate Placzek of ZRT Laboratory explains how declining estradiol disrupts brain glucose metabolism, neurotransmitter signalling and thermoregulation, why perimenopause represents a window of neurological vulnerability, and why the timing of hormone replacement therapy is critical to protecting long-term brain health.

Hot flushes, night sweats, anxiety, insomnia and brain fog — menopause can feel overwhelming. But what is actually happening biochemically? In this case study, Dr. Kate Placzek and Dr. Allison Smith walk through the test results of Julia, a newly postmenopausal woman, showing exactly how hormone and neurotransmitter imbalances drive menopausal symptoms — and what can be done about it.

In perimenopause, falling estradiol doesn’t just trigger hot flashes — it disrupts serotonin production, driving mood swings, brain fog and sleepless nights. Discover the hormonal science behind “the change” and how testing can help.

The gut microbiome and estrogen are more closely connected than most people realise. As estrogen declines in menopause, microbial diversity falls with it — triggering a cascade of metabolic consequences including weight gain, abdominal fat, inflammation and reduced insulin sensitivity. Dr. Kate Placzek explores the science behind the estrobolome and explains why supporting both gut health and hormone balance is essential for metabolic wellbeing in menopause.

The Women’s Health Initiative (WHI) trial cast a long shadow over hormone replacement therapy — but it enrolled women well over a decade past menopause. Two newer trials, ELITE and KEEPS, specifically studied HRT started early in the postmenopausal period. Their findings on cardiovascular health, sexual function, sleep, mood and cognition paint a more nuanced and encouraging picture. Here is what the latest research shows.