Episode 120: Insulin Resistance. The Hidden Cause of Fatigue, Brain Fog & Weight Gain
If you’re constantly tired, dealing with brain fog, and gaining weight despite eating well, exercising, and doing everything “right”, this episode will help you understand what’s really going on. One of the most overlooked root causes behind these symptoms is insulin resistance, a metabolic issue that often goes undetected in standard blood tests.
In this episode of our Metabolic Health Series, we break down what insulin resistance actually is, how it develops, and why it can exist for years before showing up in your lab results. You’ll learn how it impacts your energy levels, brain function, hormones, sleep, and metabolism, and why so many people are told their results are “normal” while still feeling exhausted, foggy, and stuck.
This episode answers questions like:
“What is insulin resistance?”
“Can you have insulin resistance with normal blood sugar?”
“Should I test fasting insulin?”
“What causes insulin resistance?”
“How does stress affect blood sugar?”
“What is the link between insulin resistance and hormones?”
Most importantly, this episode gives you a clear, practical starting point. You’ll understand which markers matter (including fasting insulin and HOMA-IR), why conventional testing often misses the full picture, and what a functional medicine approach to metabolic health looks like. If you’ve been feeling like your body is working against you, this episode will connect the dots—and show you what to do next.
DISCLAIMER: The content in this podcast and related website is not intended to be a substitute for medical advice. It is not intended to be used to diagnose or treat, instead it is designed to help educate and inspire. Always seek the advice of a professional medical practitioner or qualified health practitioner. Never ignore or disregard advice given to you based on information in this podcast or related website and do not delay in seeking medical advice.
Timestamps:
[03:13] - What Is Insulin & Insulin Resistance?
Understand how insulin works, how it regulates blood sugar, and what happens when cells stop responding, leading to insulin resistance.
[04:40] - What Causes Insulin Resistance?
Explore the root causes including high sugar intake, chronic stress, poor sleep, low muscle mass, and visceral fat.
[07:20]- Why Insulin Resistance Is Missed in Standard Blood Tests
Fasting glucose vs fasting insulin, HOMA-IR, and triglyceride-to-HDL ratio, what your doctor may not be testing.
[11:10] - How Insulin Resistance Affects the Body
How insulin resistance can lead to brain fog, mental fatigue, and cognitive decline, and why it makes weight loss harder through hormonal disruption and estrogen imbalance. We also explore its role in chronic inflammation and autoimmune conditions, its connection to cortisol and disrupted sleep, and how it influences cholesterol, blood pressure, and long-term cardiovascular risk.
[17:50]- Why Women in Their 30s–40s Are More Affected
Hormonal shifts, stress load, and why symptoms are often dismissed or misdiagnosed.
[20:25] - How to Reverse Insulin Resistance
Key strategies: blood sugar balance, protein intake, resistance training, and post-meal movement.
[24:45] - Supplements & Nutritional Support for Insulin Sensitivity
Magnesium, berberine, inositol, and other evidence-based tools to support metabolic health.
[26:50] - Real Client Case: Hidden Insulin Resistance Explained
A practical example showing how normal blood tests missed the root cause, and what changed.
“Insulin resistance is one of the most reversible metabolic conditions we manage in functional medicine. And this is not a qualified statement. It’s a direct one. With the right dietary approach, the right movement strategy, the right nutritional support and adequate sleep, insulin sensitivity can be meaningfully and measurably improved within weeks. This is one of the most well replicated findings in metabolic research.”
Essential learnings from this episode…
Insulin resistance can exist even with “normal” blood tests. Standard markers like fasting glucose and HbA1c often miss early insulin resistance. Testing fasting insulin and HOMA-IR gives a more accurate picture of your metabolic health.
Fatigue, brain fog, and weight gain are often driven by one root cause: insulin resistance and blood sugar dysregulation.
Insulin resistance is a whole-body condition. It doesn’t just affect blood sugar, it impacts your brain function, hormones, energy production, sleep, and immune system.
Lifestyle factors play a major role in metabolic dysfunction. Diet, chronic stress, poor sleep, and low muscle mass all contribute to reduced insulin sensitivity over time.
Women in their 30s and 40s are at higher risk. Hormonal shifts, stress, and metabolic changes make insulin resistance more likely, yet symptoms are often dismissed as aging or burnout.
Insulin resistance is reversible with the right approach. Targeted nutrition, movement (especially resistance training), sleep optimization, and key nutrients can improve insulin sensitivity in weeks.
EPISODE 120
Important links & mentions from this episode
The Optimal You 7 Day Reset (£7.99)
Goode Health Clinic Functional Medicine Packages
Take the FREE MitoImmune Health Assessment
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