What happens during a 3-day fast

Most people think fasting is just about skipping breakfast. But what if 72 hours without food could actually reverse aging?

In this video, Dave Asprey breaks down what really happens when you fast for 3 days—and why short fasts don’t reach the deep repair zone your body is built for.

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Chapters

0:00 - Why 16-hour fasts don’t reach real fat burning

0:54 - The myth of aging and what doctors overlook

1:48 - How modern life damages your mitochondria

2:48 - How fasting restores your body’s repair mode

3:39 - Understanding the phases of fasting

4:58 - Why short fasts cut results short

5:34 - Day 1 of fasting

6:45 - Day 2 of fasting

7:22 - Day 3 of fasting

8:24 - Common fasting mistakes that harm your body

9:35 - How to prepare before your fast

10:31 - The right way to refeed afterward

11:14 - Listening to your body’s signals and responses

Resources:   

• Go To:  www.qualialife.com/humanupgrade for an automatic extra 15% discount to try Qualia Creatine. 

• Get My 2026 Biohacking Trends Report: https://daveasprey.com/2026-biohacking-trends-report/ 

• Join My Low-Oxalate 30-Day Challenge: https://daveasprey.com/2026-low-ox-reset/ 

• Dave Asprey's Latest News | Go to https://daveasprey.com/ to join Inside Track today.  

• Danger Coffee: https://dangercoffee.com/discount/dave15   

• My Daily Supplements: SuppGrade Labs (15% Off)   

• Favorite Blue Light Blocking Glasses: TrueDark (15% Off)   

• Dave Asprey’s BEYOND Conference: https://beyondconference.com   

• Dave Asprey’s New Book – Heavily Meditated: https://daveasprey.com/heavily-meditated  

• Upgrade Collective: https://www.ourupgradecollective.com   

• Upgrade Labs: https://upgradelabs.com   

• 40 Years of Zen: https://40yearsofzen.com  

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