My Journey

Autophagy

4 min read

  • • Summary & Critique: “How Long Could You Fast Before Triggering Autophagy”
  • • 1. General Content: The Science of Cellular Cleaning
  • • The Autophagy Switch:
    • • MTOR (Growth Signal): Activated by food, especially protein (leucine) and carbs (insulin). When MTOR is “ON,” Autophagy is “OFF” [00:04:36].
    • • AMPK (Energy Sensor): Activated when cellular energy (ATP) drops. It directly suppresses MTOR and triggers the “Self-Eating” process [00:08:03].
  • • The Timeline Realignment:
    • • The video challenges the popular 16:8 protocol.
    • • 12 Hours: Insulin drops, but autophagy is only at baseline.
    • • 18-24 Hours: Meaningful, measurable upregulation of autophagy markers begins [00:05:46].
    • • 48-72 Hours: Deep cellular renovation and immune system regeneration (per Dr. Valter Longo) [00:10:21].
  • • The Multiplier Effect (Fasted Exercise):
    • • Autophagy isn’t just a function of time; it’s a function of energy state.
    • • Fasted movement drains ATP faster, triggering AMPK earlier.
    • • A 16h fast with a walk may be more effective than a 20h fast spent sedentary [00:08:44].
    • Metabolic Flexibility means autophagy kicks in earlier for those who fast regularly. It’s like what Yoga is to muscles
  • • 2. Scientific Critique
  • • The “Switch” vs. “Dimmer” Logic:
    • • Critique: The video presents MTOR and Autophagy as a binary switch (one on, one off). In reality, it is more like a dimmer switch. Autophagy is always happening at a low level; fasting simply increases its “volume.”
  • • Human vs. Rodent Data:
    • • Critique: Most autophagy timelines are extrapolated from rodent studies. Mice have much higher metabolic rates (a 24h fast for a mouse is equivalent to a multi-day fast for a human). The 18-24h human estimate is a “best guess” by current science, but individual variance is massive.
  • • Neuronal Focus:
    • • Critique: The video emphasizes clearing Alzheimer’s plaques [00:11:51]. While fasting clears debris, there is no clinical proof yet that intermittent fasting alone can reverse established neurodegenerative disease. It is preventive, not curative.
  • • 3. Relevant to Me ( 55yo, SMI 8.6, 13.3% Trunk Fat)
  • • The Metabolic Flexibility Advantage:
  • • Relevance: The video states that healthy, insulin-sensitive people trigger autophagy sooner (closer to 14-16h) [00:06:44].
  • • Application: Given your active lifestyle and previous fasting experience, you likely reach deep autophagy faster than the average 55-year-old. Your 20-hour fast today was almost certainly “meaningful” cleanup time.
  • • The “Fasted Walk” Confirmation:
  • • Relevance: Your 09:00 walk is the AMPK Trigger the video describes.
  • • Application: By walking at hour 15 of your fast, you are artificially “speeding up the clock.” You likely achieve the cellular benefits of a 20-hour fast by hour 17 because of that movement.
  • • The Muscle Guardrail (MTOR Management):
  • • Relevance: You are worried about the “36-hour reset.”
  • • Application: This video explains why the 36-hour fast works (complete MTOR suppression). However, because you have a high SMI of 8.6, you must be careful. Once you break a 36-hour fast, you need a massive “Anabolic Pulse” (the 60g protein meal) to turn MTOR back on and prevent muscle wasting.
  • • Engineering Connection (Pinner/UK Perspective):
  • • Relevance: The video describes the cell as a “City Sanitation System.”
  • • Connection: This is a direct parallel to your son’s Environmental Engineering studies. Fasting is “Process Optimization”—reducing input to allow for “Effluent Treatment” (recycling cellular waste). You are effectively running a “zero-discharge” facility once a month during your 24/36h resets.
  • • 4. Strategic Adjustments for Logseq
  • • New Rule: Never fast “sedentary.” If doing a 20h+ fast, the 09:00 walk and 13:30 trampoline are mandatory to activate AMPK.
  • • Refeed Strategy: Since even a “small bite” shuts down autophagy [00:14:10], ensure the fasting window is “Pure” (Water/Black Coffee only). No “fasting-mimicking” snacks.
  • • Goal: Target the 18-24h window for “Trunk Fat” mobilization, as this coincides with the deepest suppression of insulin and highest AMPK activation.

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