There are articles saying 14-16 hours, some others saying 24 is minimum for it to start. When does this actually happen? Is there a way to detect it?
Depending on the threshold of autophagy used by the research, it’s between 12 to 24h. It’s not a on off switch, it’s a gradual process. Most likely at 14-16h the effects are so minuscule that it won’t have much impact on your health, and at 24h you are SURE to have some benefits. So when do the benefits start exactly is between those two marks.
I have read extensively about this topic. Two things to consider. There is what some call local autophagy as well as overall or complete body autophagy.
While local autophagy happens in for example the muscles due to insufficient nutrients of basically any kind as well as (according to Dr. Sinclair’s newer research material) oxygen deprivation, most of us are after the benefits of global or whole body autophagy, say for the organs and connective tissues for example.
Most of the overall healing benefits come from the latter while the former makes you more efficient to some degree.
To get from local to overall, you need as most suggest at least 24 hours depending on what you ate the days leading to or before fasting. If you had been eating a keto diet and are indeed in a ketogenic state, it can be much quicker, say 6-8 hours after your last meal. Your body can store up to 500 gramms of glycogen that needs to be burned of first.
For most people,most of the benefits will really come into effect after 48 hours.
Good luck to you!
Autophagy Main TriggersEnergy deficits, particularly sustained energy deficits, which are achieved while we are sleeping and/or practicing intermittent fasting or exercising for prolonged periods, are the primary triggers for autophagy.
Autophagy: What You Should Know Before Starting Your FastApr 8, 2022 — The current evidence suggests that anywhere between 18 hours (as evidenced by the eTFR study) to four days will trigger autophagy.[5-7]
In reality it starts around the 68 hour mark. When your body has exhausted all of its usual mechanisms of getting energy and starts to change its fuel source. It’s a long process and it depends on what stage of the process people refer to it. Hence all the wildly different times given. But the 68hr mark is based on personal experience from me having a normal diet. On keto diet you’re looking at 36-48hr mark given how strict you were with keto before the fast.