I’m going to have to agree with @BillJay after looking more into Dr. Valter Longo’s Fasting Mimicking Diet (FMD) it appears that autophagy does happen on a continuum. With the suppression of IGF-1 and mTOR, autophagy appears to ramp up. I believe the effects can start to be seen around day 3, but are very robust on day 5. Protien, especially leucine and methionine, will activate these pathways. Carbohydrates will activate these pathways to a lesser degree, though still substantial enough, as will beta-oxidation, but probably to a negligible effect. I believe I heard somewhere that the FMD suppresses the metabolic pathways around 80% that of water fasting. Dr. Longo’s team is looking more into the effects of his FMD and autophagy. In his patent the FMD looks like this:
**Day 1:** 10 to 16 calories per kg bodyweight, 10% protein, 56% fat, 34% carbs
**Days 2 – 5:** 7 to 11 calories per kg bodyweight, 9% protein, 44% fat, 47% carbs
Using myself for example (I weigh 140lbs, or 64kg), starting on Day 2, my total calories would be 450-700, with protein at 10g-15g, and carbs at 52g-82g.
To me, and I’m sure any keto-adapted person, the carb content seems high, but he’s getting outstanding results in animal and human clinical trials. I just completed a modified version of this, hoping it would be superior and more in line with being already keto-adapted. All 5 days I stayed below 10g of protein and 10g of carbs, which makes 80 calories, and I filled the rest of my calories in the range I mentioned above with fat. Both protein and carb macros were obtained from greens, avocado, nuts/seeds (salad contains amino acids and when you’re limited to 10g a day, the amount of protein from greens is significant); I ate no animal protein except one day I had an egg yolk…yum
In response to @riportner, I believe (and this is purely speculative) that being already keto-adapted with lowered carbs and insulin will give a head start, but by how much? Probably not a whole lot but it does take carb-adapted people around 48 hours+ to get ketones even near that of keto-adapted individuals. I’m sure our head start into deeper ketosis for longer has a greater therapeutic effect in some way, but as far as autophagy goes, I think what matters more is the protein aspect, which is why I think, we don’t get that great a head start. I could be wrong, hopefully the science comes out soon, until then, happy experimenting.