>>It is well established that short-term starvation in humans induces insulin resistance.

Indeed. Switching the skeletal muscles from glucose metabolism to ketones preserves glucose for the CNS. Further fasting induces autophagy, which is the main reason people voluntarily fast as it is a method to remove senescent cells, and so reduce inflammation.

Speaking of voluntary fasting and ketosis, it might be worth investigating those people either fasting or living on a low carb diet, particularly vegetarians, for signs of fluid retention. I haven't seen any mention of it, but it's not something I've been looking for; I'm more interested in the roots of the cascade that ends metabolic flexibility (the ability to switch between the two metabolisms). So far, it seems to start in the skeletal muscles with something (fat buildup?) in the cells interfering with GLUT4, which normally transports glucose into the cell in the presence of insulin, and the issue cascades from there (periphery inwards). What causes that fat buildup? Dunno, but the signs are towards a mitochondrial disfunction of some kind. World class athletes have a fat buildup around their mitochondria. So do people with type 2. The rest of us pretty much do not.

Just reasoning aloud here...

Disclaimer: I'm not bio accredited, just someone with decent reading comprehension who got interested a couple of decades ago.