Episode 108: The Biology of Energy: Mitochondria, Hormones, Blood Sugar & Inflammation
Energy is often treated as a mindset problem, something to fix with motivation, discipline, or better routines. But real, sustainable energy is created inside the body. In this episode of The Good Health Podcast, Certified Functional Medicine Practitioner Nicole Good breaks down the biology of energy, explaining why fatigue is rarely about one single issue and why “doing all the right things” doesn’t always translate into feeling energized.
This episode explores how mitochondrial function, hormone timing (especially cortisol and circadian rhythm), blood sugar stability, and low-grade inflammation work together to determine how much energy your body can produce, and when that energy is available. You’ll learn why mitochondria often dial energy down as a protective response, how stress disrupts cortisol rhythm, why blood sugar volatility creates energy crashes, and how chronic immune activation quietly diverts energy away from daily functioning.
This episode answers questions like:
“What actually controls energy in the body?”
“How do mitochondria affect fatigue?”
“How cortisol rhythm affects energy”
“Why blood sugar crashes cause fatigue”
“Why inflammation makes you tired”
“Why energy feels unstable during the day”
If you struggle with persistent low energy, afternoon slumps, feeling wired at night but exhausted in the morning, or fatigue that doesn’t improve with sleep or nutrition alone, this episode will give you a clear, systems-based framework for understanding what your body is responding to.
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:
[00:50] - Energy Is Not a Mindset Problem
Why motivation and discipline don’t create energy, and why fatigue starts in the body, not the mind.
[03:00] - How Energy Is Created at a Cellular Level
How chronic stress, nutrient depletion, poor sleep, and low-grade inflammation reduce mitochondrial efficiency, without “breaking” the system.
[06:00] - Cortisol, Circadian Rhythm & Energy Timing
How cortisol rhythm determines when energy is available, not just how much energy you have. And why feeling exhausted in the morning but alert at night is a circadian rhythm issue.
[08:40] - Blood Sugar Instability & Energy Crashes
How blood sugar volatility creates energy dips, brain fog, cravings, and afternoon slumps.
[11:10] - Low-Grade Inflammation & Immune Activation
How chronic immune activation silently diverts energy away from daily functioning.
[13:30] - A New Framework for Supporting Energy
Why sustainable energy comes from removing biological barriers, not pushing harder.
“Low energy is rarely about a lack of effort. More often, it’s about mitochondria reducing output because the environment doesn’t feel supportive. Chronic stress, inflammation, poor sleep, or nutrient depletion signal the body to conserve energy rather than optimise it. Energy hasn’t stopped being produced, it’s been dialled down as a protective response.”
Essential learnings from this episode…
Energy is produced inside your cells by mitochondria, not by motivation, mindset, or willpower. When cellular conditions aren’t supportive, energy output is deliberately reduced.
Mitochondria reduce energy production in response to stress, inflammation, nutrient depletion, or poor sleep. This is adaptation, not damage, and efficiency can be restored.
Fatigue is often caused by disrupted circadian rhythm rather than “too much” or “too little” cortisol. Poor timing interferes with sleep, repair, and daily energy stability.
Fluctuating blood sugar creates unpredictable energy, brain fog, cravings, and afternoon slumps, even in people eating “healthy” diets under chronic stress.
Low-grade inflammation and immune activation divert energy toward defense instead of daily functioning, often without showing up on standard blood tests.
Energy is the result of mitochondria, hormones, blood sugar regulation, and immune signaling working together. Supporting energy means removing biological barriers, not doing more.
EPISODE 108
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