Uploaded May 2026 | Updated September 2026, 3 weeks ago
Fasting is one of the most powerful healing practices in human history—it’s free, requires zero equipment, and your body is literally designed for it. But while it sounds simple, there is a wrong way to do it, especially when it comes to the hormonal "engine switch" that happens in the first 24 hours. In this episode, I walk you through exactly what happens in your body during a 3-day fast, from clearing out "zombie cells" to the 60% drop in aging markers.
Thank you to our sponsors!
Sunlighten Sauna: get.sunlighten.com/axepodcast
Manukora Manuka Honey: manukora.com/axe
Caraway Home: carawayhome.com/drjoshaxe (Use code DRJOSHAXE) for an exclusive discount
Watch The Dr. Josh Axe Show every Monday & Thursday on YouTube: youtube.com/@drjoshaxe?sub_confirmation=1
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Our listeners enjoy every episode before anyone else! Tune in below and join our exclusive group of listeners →
Spotify: bit.ly/DrJoshAxeSpotify
Apple Podcast: apple.co/3JDvWcS
Pre-order my NEW BOOK, Heal Your Cells → bit.ly/3QJBcQ5
Watch my free training on how to naturally balance your blood sugar and reverse your symptoms → DrAxeDiabetesClass.com
Discover practical steps you can take today to start healing your thyroid naturally → DrAxeThyroidClass.com
If you’re ready to start feeling like yourself again and balance your hormones, take my free class → DrAxeHormoneClass.com
Uncover what’s really going on in your body with advanced biomarker testing for hormones, thyroid, and metabolism— plus a 1-hour consultation with a Senior Health Advisor! → mybloodwork.com
CONNECT WITH DR. JOSH AXE
Instagram → instagram.com/drjoshaxe
Facebook → facebook.com/DrJoshAxe
TikTok → tiktok.com/@thedrjoshaxeshow
X → https://x.com/drjoshaxe/
LinkedIn → linkedin.com/in/joshaxe
Website → thehealthinstitute.com
Sign up for my newsletter → bit.ly/4oE9Jf3
Ask Dr. Axe → speakpipe.com/drjoshaxe
Timestamps
0:00 —Intro
1:11 — Why Insulin Never Drops for Americans
2:35 — Hour 24: The Insulin & Glycogen Drop
4:05 — The "Engine Switch": Headaches and Irritability
5:57 — Ghrelin Spikes & The 20-Minute Rule
8:12 — Hour 36: Ketosis and Mental Clarity
9:04 — Autophagy: Nobel Prize Winning Cleanup
11:15 — mTOR vs. Ampk: The Build & Repair Signals
13:30 — Zombie Cell Cleanup Explained
15:30 — The Spiritual Discipline of Fasting
17:00 — Hour 72: Stem Cell Regeneration
20:40 — Who Benefits Most from Fasting?
24:16 — Warning: Who Should NOT Fast
26:25 — Men vs. Women: Hormonal Differences
30:30 — The Safe 3-Day Protocol: Electrolytes & Breaking
Links:
Insulin drop during fasting: Molecular Metabolism — pmc.ncbi.nlm.nih.gov/articles/PMC7471620
Glycogen storage: Cleveland Clinic — my.clevelandclinic.org/health/articles/23509-glycogen
Ghrelin and meal timing: Diabetes Journal — diabetesjournals.org/diabetes/article-abstract/50/8/1714
Growth hormone 14x study: Frontiers in Endocrinology — pmc.ncbi.nlm.nih.gov/articles/PMC11842881
Ketones and brain energy: Annals of Medicine — pmc.ncbi.nlm.nih.gov/articles/PMC7877980
Nobel Prize — Autophagy (Ohsumi): nobelprize.org/prizes/medicine/2016/press-release
Insulin resistance prevalence: StatPearls / NCBI — ncbi.nlm.nih.gov/books/NBK507839
Immune stem cell reset: USC Valter Longo Lab — https://stemcell.keck.usc.edu/fasting-triggers-stem-cell-regeneration-of-damaged-old-immune-system/
Muscle loss during fasting: Nutrients — pmc.ncbi.nlm.nih.gov/articles/PMC9503095
Food addiction data: Michigan Medicine — michiganmedicine.org/health-lab/1-8-americans-over-50-show-signs-food-addiction
The Didache (c. 100 AD): Chapter 8
DISCLAIMER
This content is strictly the opinion of Dr. Josh Axe and is for informational and educational purposes only. It is not intended to provide medical advice or to take the place of medical advice or treatment from a personal physician. All viewers of this content are advised to consult their doctors or qualified health professionals regarding specific health questions. Neither Dr. Axe nor the publisher of this content takes responsibility for possible health consequences of any person or persons reading or following the information in this educational content. All viewers of this content, especially those taking prescription or over-the-counter medications, should consult their physicians before beginning any nutrition, supplement or lifestyle program.
MB011DB7DLOWW9T
Fasting is one of the most powerful healing practices in human history—it’s free, requires zero equipment, and your body is literally designed for it. But while it sounds simple, there is a wrong way to do it, especially when it comes to the hormonal "engine switch" that happens in the first 24 hours. In this episode, I walk you through exactly what happens in your body during a 3-day fast, from clearing out "zombie cells" to the 60% drop in aging markers.
Thank you to our sponsors!
Sunlighten Sauna: get.sunlighten.com/axepodcast
Manukora Manuka Honey: manukora.com/axe
Caraway Home: carawayhome.com/drjoshaxe (Use code DRJOSHAXE) for an exclusive discount
Watch The Dr. Josh Axe Show every Monday & Thursday on YouTube: youtube.com/@drjoshaxe?sub_confirmation=1
🎧 Early Access!
Our listeners enjoy every episode before anyone else! Tune in below and join our exclusive group of listeners →
Spotify: bit.ly/DrJoshAxeSpotify
Apple Podcast: apple.co/3JDvWcS
Pre-order my NEW BOOK, Heal Your Cells → bit.ly/3QJBcQ5
Watch my free training on how to naturally balance your blood sugar and reverse your symptoms → DrAxeDiabetesClass.com
Discover practical steps you can take today to start healing your thyroid naturally → DrAxeThyroidClass.com
If you’re ready to start feeling like yourself again and balance your hormones, take my free class → DrAxeHormoneClass.com
Uncover what’s really going on in your body with advanced biomarker testing for hormones, thyroid, and metabolism— plus a 1-hour consultation with a Senior Health Advisor! → mybloodwork.com
CONNECT WITH DR. JOSH AXE
Instagram → instagram.com/drjoshaxe
Facebook → facebook.com/DrJoshAxe
TikTok → tiktok.com/@thedrjoshaxeshow
X → https://x.com/drjoshaxe/
LinkedIn → linkedin.com/in/joshaxe
Website → thehealthinstitute.com
Sign up for my newsletter → bit.ly/4oE9Jf3
Ask Dr. Axe → speakpipe.com/drjoshaxe
Timestamps
0:00 —Intro
1:11 — Why Insulin Never Drops for Americans
2:35 — Hour 24: The Insulin & Glycogen Drop
4:05 — The "Engine Switch": Headaches and Irritability
5:57 — Ghrelin Spikes & The 20-Minute Rule
8:12 — Hour 36: Ketosis and Mental Clarity
9:04 — Autophagy: Nobel Prize Winning Cleanup
11:15 — mTOR vs. Ampk: The Build & Repair Signals
13:30 — Zombie Cell Cleanup Explained
15:30 — The Spiritual Discipline of Fasting
17:00 — Hour 72: Stem Cell Regeneration
20:40 — Who Benefits Most from Fasting?
24:16 — Warning: Who Should NOT Fast
26:25 — Men vs. Women: Hormonal Differences
30:30 — The Safe 3-Day Protocol: Electrolytes & Breaking
Links:
Insulin drop during fasting: Molecular Metabolism — pmc.ncbi.nlm.nih.gov/articles/PMC7471620
Glycogen storage: Cleveland Clinic — my.clevelandclinic.org/health/articles/23509-glycogen
Ghrelin and meal timing: Diabetes Journal — diabetesjournals.org/diabetes/article-abstract/50/8/1714
Growth hormone 14x study: Frontiers in Endocrinology — pmc.ncbi.nlm.nih.gov/articles/PMC11842881
Ketones and brain energy: Annals of Medicine — pmc.ncbi.nlm.nih.gov/articles/PMC7877980
Nobel Prize — Autophagy (Ohsumi): nobelprize.org/prizes/medicine/2016/press-release
Insulin resistance prevalence: StatPearls / NCBI — ncbi.nlm.nih.gov/books/NBK507839
Immune stem cell reset: USC Valter Longo Lab — https://stemcell.keck.usc.edu/fasting-triggers-stem-cell-regeneration-of-damaged-old-immune-system/
Muscle loss during fasting: Nutrients — pmc.ncbi.nlm.nih.gov/articles/PMC9503095
Food addiction data: Michigan Medicine — michiganmedicine.org/health-lab/1-8-americans-over-50-show-signs-food-addiction
The Didache (c. 100 AD): Chapter 8
DISCLAIMER
This content is strictly the opinion of Dr. Josh Axe and is for informational and educational purposes only. It is not intended to provide medical advice or to take the place of medical advice or treatment from a personal physician. All viewers of this content are advised to consult their doctors or qualified health professionals regarding specific health questions. Neither Dr. Axe nor the publisher of this content takes responsibility for possible health consequences of any person or persons reading or following the information in this educational content. All viewers of this content, especially those taking prescription or over-the-counter medications, should consult their physicians before beginning any nutrition, supplement or lifestyle program.
MB011DB7DLOWW9T
