Fasted FASTED

Autophagy Timer

Track your progress toward autophagy — the cellular recycling process that kicks in during extended fasts. See estimated timelines based on research averages.

Heavier meals delay autophagy; lighter meals or depletion accelerate it.

Exercise can accelerate autophagy onset by ~1 hour.

Autophagy begins in

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Start your fast to begin tracking

0% to initiation
🔒 Initiation

16h

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Cells begin recycling damaged proteins and organelles. Damaged components are tagged for breakdown.

🔒 Active

24h

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Full cellular cleanup is under way. Immune cells regenerate and inflammation markers drop.

🔒 Deep

48h

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Maximum autophagy. Stem cell regeneration, significant immune renewal, and deep cellular repair.

What is autophagy, really?

Autophagy (from the Greek "auto" meaning self and "phagein" meaning to eat) is your body's built-in recycling system. When you fast for an extended period, your cells begin breaking down old, damaged, or dysfunctional components — misfolded proteins, worn-out organelles, and cellular debris — and repurpose the raw materials into new, functional parts. Think of it as a deep clean at the cellular level.

This process was largely unknown to the public until Yoshinori Ohsumi won the 2016 Nobel Prize in Physiology or Medicine for his work on the mechanisms of autophagy. Since then, research has linked autophagy to a range of potential health benefits: improved immune function, reduced inflammation, protection against neurodegenerative diseases, and even longevity. Fasting is one of the most potent natural triggers for this process.

The timeline varies from person to person. Factors like your metabolic health, body composition, activity level, and what you ate before the fast all influence when autophagy begins. The thresholds shown here are based on research averages and should be treated as educated estimates, not precise measurements.

Important disclaimer

Autophagy cannot be measured without specialised laboratory testing. These timelines are based on research averages and are not a diagnosis or medical measurement. Individual results vary significantly based on metabolic health, body composition, and other factors. Consult a healthcare professional before undertaking extended fasts.

Autophagy is one of the most compelling reasons people extend their fasts beyond the standard 16-hour window. This cellular recycling process, where your body breaks down and repurposes damaged cells, has been linked to longevity, reduced inflammation, and disease prevention.

Tracking when autophagy begins during your fast transforms an abstract scientific concept into something tangible and motivating. Seeing the timer count into the autophagy zone gives you a clear reason to push through the later hours of a longer fast.

Frequently Asked Questions

When does autophagy start during fasting?
Autophagy begins at a low level after about 16-18 hours of fasting and increases significantly around the 24-hour mark. Deep autophagy, where substantial cellular cleanup occurs, is believed to peak between 48-72 hours. However, meaningful autophagy benefits can accumulate from regular shorter fasts as well.
Can you feel autophagy happening?
You cannot directly feel autophagy as a specific sensation. However, many long-term fasters report improved mental clarity, reduced inflammation, and better skin quality, which are associated with autophagy. The process happens at a cellular level and its effects become apparent gradually over weeks and months of regular fasting.
Does exercise speed up autophagy during fasting?
Research suggests that exercise can independently trigger autophagy and may amplify the autophagic response when combined with fasting. Moderate-intensity exercise during a fast appears to accelerate the process, though extremely intense exercise while fasted may not be advisable for everyone.
How long do I need to fast for full autophagy benefits?
There is no single threshold for "full" autophagy, as it increases progressively the longer you fast. Regular 18-24 hour fasts provide meaningful autophagy benefits over time. Occasional longer fasts of 36-48 hours can deepen the process, but they should be approached carefully and are not necessary for most people.
What breaks autophagy during a fast?
Consuming calories, particularly protein and carbohydrates, activates mTOR and insulin pathways that suppress autophagy. Even small amounts of food can interrupt the process. Water, black coffee, and plain tea are generally considered safe and may even support autophagy.

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