10 August 2026
The Hidden Cause of Weight Gain, Fatigue & Brain Fog in Women Over 40 | Dr. Amie Hornaman
High Performance Health
About
Labs read "normal" but you're gaining midsection weight, foggy and running at 70%? Your thyroid - not just perimenopause - may be the missing variable. Dr. Amie Hornaman explains why TSH alone misses the picture, how elevated reverse T3 "pools" and blocks T3 at the cell even when free T3 looks optimal, and why roughly 98% of women don't thrive on T4-only. She links falling progesterone, rising thyroid-binding globulin, low ferritin and the "thyropause" hitting 80-90% of women over 40.
WHAT YOU'LL LEARN
Why a "normal" TSH can completely miss a thyroid problem - and the five markers that actually reveal what's happening
What reverse T3 "pooling" is, and how it blocks active thyroid hormone at the cell even when your free T3 looks optimal
Why roughly 98% of women stop thriving on T4-only medication once they're past 40
How falling progesterone drives estrogen dominance, raises thyroid binding globulin, and quietly strands thyroid hormone before it reaches the cell
What "thyropause" is, why it hits 80-90% of women over 40, and how it overlaps with the perimenopause symptoms you're blaming instead
Why testosterone acts as armor against autoimmunity - and what its decline switches on
How low ferritin, insulin resistance and cortisol compound thyroid-driven fatigue and stubborn belly fat
TIMESTAMPS
00:00 - Intro: Why Midlife Women Go Undiagnosed & the Full Thyroid Panel Doctors Skip (TSH, Free T3/T4, Reverse T3, Antibodies)09:46 - Reverse T3 "Pooling," Why T4-Only Fails Most Women & What Actually Drives High Reverse T317:28 - How HRT, Progesterone Loss & Low Ferritin Hit Your Thyroid - Plus the "Thyropause" Switch22:09 - Core Thyroid Nutrients, Iodine Dosing Do's & Don'ts, and How to Actually Fix Low Iron40:14 - High Antibodies and Still Optimized? Hashimoto's Triggers & Protecting Your Thyroid45:40 - Midlife Belly Fat & Bloating: Root Causes, Smart Testing Order & the Gut-Healing Myth53:12 - Thyropause & Lean Athletes: Why Most Women Over 40 Get Hit - Plus The Thyroid Fix Book
VALUABLE RESOURCES
The Thyroid Fix (Dr. Amie's book) https://thyroidfixbook.com/
Dr. Amie Hornaman's website / book a call https://dramie.com/
Fixxr Supplements (Dr. Amie's line, incl. iodine) https://dramiehornaman.com/collections/supplements
Follow Dr. Amie on Instagram https://www.instagram.com/dramiehornaman/
Thanks to my sponsor, Eight Sleep
Sleep cooler, recover faster. The Eight Sleep Pod pre-cools your bed and adjusts all night for deeper sleep - dual-zone, so you and your partner each get your own temp.
👉 https://www.eightsleep.com/hph - code ANGELA for up to £350 off. 30-night trial.
ABOUT THE GUEST
Dr. Amie Hornaman, known worldwide as "The Thyroid Fixer," holds a doctorate in clinical nutrition and functional medicine and is the founder of the Advanced Thyroid and Hormone Clinic, a telehealth practice serving patients across all 50 US states. A fitness model turned functional-medicine doctor, her work grew out of her own years of misdiagnosis and dismissed symptoms - the experience behind her mission to help women decode their labs and get optimal, not merely "normal," thyroid care. She hosts the top-rated Thyroid Fixer Podcast and created the Fixxr supplement line. Her latest book, The Thyroid Fix, is a no-nonsense handbook on testing, dosing, and self-advocacy for the underdiagnosed thyroid epidemic in women.
Want to go deeper? Start here:
Take the BioSyncing Quiz to help you understand what’s actually happening in your body - and how to fix it.
👉 https://biosyncing.scoreapp.com
🌸Reset your hormones, restore your energy, and reconnect with your body in just 21 days.
👉 https://www.highperformance-health.com
💌 Fresh Start Sundays Newsletter
Your weekly 3-minute guide to creating the healthiest, most vibrant version of you.
Each Monday, get one simple habit to boost energy, balance hormones, and enhance longevity - joined by 25,000+ women worldwide.
👉 https://angelafosterperformance.com/
🥗 The Ultimate Guide to Creatine for Women
👉 https://academy.angelafosterperformance.com/creatine-guide
⚡ 10 Habits That Helped Me Reverse My Biological Age by 25 Years During Perimenopause
👉 https://academy.angelafosterperformance.com/10-habits-optin-page
👩💼 About Angela Foster
Angela Foster is a corporate lawyer turned health and performance coach, keynote speaker, and creator of the BioSyncing® Method. She is the host of the High Performance Health Podcast, featuring over 500 conversations with world-leading experts in longevity, hormones, neuroscience, nutrition, and female performance.
Angela's mission is to help one million ambitious women optimise their hormones, energy, cognitive performance, and longevity, so they never have to choose between success and their health.
If you enjoyed this episode, please subscribe, leave a review, and share it with someone who would benefit from it.
Follow me for daily health and performance tips:
Instagram: https://www.instagram.com/angelasfoster/
Facebook: https://www.facebook.com/AngelaFosterPerformance
#AngelaFoster #HighPerformanceHealth #Longevity #HealthyAgeing
WHAT YOU'LL LEARN
Why a "normal" TSH can completely miss a thyroid problem - and the five markers that actually reveal what's happening
What reverse T3 "pooling" is, and how it blocks active thyroid hormone at the cell even when your free T3 looks optimal
Why roughly 98% of women stop thriving on T4-only medication once they're past 40
How falling progesterone drives estrogen dominance, raises thyroid binding globulin, and quietly strands thyroid hormone before it reaches the cell
What "thyropause" is, why it hits 80-90% of women over 40, and how it overlaps with the perimenopause symptoms you're blaming instead
Why testosterone acts as armor against autoimmunity - and what its decline switches on
How low ferritin, insulin resistance and cortisol compound thyroid-driven fatigue and stubborn belly fat
TIMESTAMPS
00:00 - Intro: Why Midlife Women Go Undiagnosed & the Full Thyroid Panel Doctors Skip (TSH, Free T3/T4, Reverse T3, Antibodies)09:46 - Reverse T3 "Pooling," Why T4-Only Fails Most Women & What Actually Drives High Reverse T317:28 - How HRT, Progesterone Loss & Low Ferritin Hit Your Thyroid - Plus the "Thyropause" Switch22:09 - Core Thyroid Nutrients, Iodine Dosing Do's & Don'ts, and How to Actually Fix Low Iron40:14 - High Antibodies and Still Optimized? Hashimoto's Triggers & Protecting Your Thyroid45:40 - Midlife Belly Fat & Bloating: Root Causes, Smart Testing Order & the Gut-Healing Myth53:12 - Thyropause & Lean Athletes: Why Most Women Over 40 Get Hit - Plus The Thyroid Fix Book
VALUABLE RESOURCES
The Thyroid Fix (Dr. Amie's book) https://thyroidfixbook.com/
Dr. Amie Hornaman's website / book a call https://dramie.com/
Fixxr Supplements (Dr. Amie's line, incl. iodine) https://dramiehornaman.com/collections/supplements
Follow Dr. Amie on Instagram https://www.instagram.com/dramiehornaman/
Thanks to my sponsor, Eight Sleep
Sleep cooler, recover faster. The Eight Sleep Pod pre-cools your bed and adjusts all night for deeper sleep - dual-zone, so you and your partner each get your own temp.
👉 https://www.eightsleep.com/hph - code ANGELA for up to £350 off. 30-night trial.
ABOUT THE GUEST
Dr. Amie Hornaman, known worldwide as "The Thyroid Fixer," holds a doctorate in clinical nutrition and functional medicine and is the founder of the Advanced Thyroid and Hormone Clinic, a telehealth practice serving patients across all 50 US states. A fitness model turned functional-medicine doctor, her work grew out of her own years of misdiagnosis and dismissed symptoms - the experience behind her mission to help women decode their labs and get optimal, not merely "normal," thyroid care. She hosts the top-rated Thyroid Fixer Podcast and created the Fixxr supplement line. Her latest book, The Thyroid Fix, is a no-nonsense handbook on testing, dosing, and self-advocacy for the underdiagnosed thyroid epidemic in women.
Want to go deeper? Start here:
Take the BioSyncing Quiz to help you understand what’s actually happening in your body - and how to fix it.
👉 https://biosyncing.scoreapp.com
🌸Reset your hormones, restore your energy, and reconnect with your body in just 21 days.
👉 https://www.highperformance-health.com
💌 Fresh Start Sundays Newsletter
Your weekly 3-minute guide to creating the healthiest, most vibrant version of you.
Each Monday, get one simple habit to boost energy, balance hormones, and enhance longevity - joined by 25,000+ women worldwide.
👉 https://angelafosterperformance.com/
🥗 The Ultimate Guide to Creatine for Women
👉 https://academy.angelafosterperformance.com/creatine-guide
⚡ 10 Habits That Helped Me Reverse My Biological Age by 25 Years During Perimenopause
👉 https://academy.angelafosterperformance.com/10-habits-optin-page
👩💼 About Angela Foster
Angela Foster is a corporate lawyer turned health and performance coach, keynote speaker, and creator of the BioSyncing® Method. She is the host of the High Performance Health Podcast, featuring over 500 conversations with world-leading experts in longevity, hormones, neuroscience, nutrition, and female performance.
Angela's mission is to help one million ambitious women optimise their hormones, energy, cognitive performance, and longevity, so they never have to choose between success and their health.
If you enjoyed this episode, please subscribe, leave a review, and share it with someone who would benefit from it.
Follow me for daily health and performance tips:
Instagram: https://www.instagram.com/angelasfoster/
Facebook: https://www.facebook.com/AngelaFosterPerformance
#AngelaFoster #HighPerformanceHealth #Longevity #HealthyAgeing