I’m not the official 180-responder, so this is just my opinion… but…
If your metabolism is low, I think you’ve basically shutdown or limited a lot of the communication highways between all your body systems. With a low metabolism, EVERYTHING just responds slower…
One take on insulin resistance, is that by using ‘fake food’ (i.e. artificial sweeteners), you’ve trained your body to ignore “sweetness” signals from the brain, as it’s not actual sugar.
When you “eat the food” and eat enough of the real stuff… you start to build new lanes on the communication highways. And when you eat real sugar (white, brown, honey, fruit, etc), you also re-train your insulin systems to ‘gear up’ for ‘sweetness’… as it IS real sugar, now.
I think you probably need to be careful in how you approach ‘re-feeding’ if you are insulin resistant – in that you might need to start slow. You don’t want to put yourself in a sugar coma!!
As for scientific studies on the issue…Here’s a start:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2951976/
The references might offer more details, too.
Try to be objective in reading their conclusions. The human body is complex, and I think an individual’s starting point (metabolically speaking) has a LOT to do with how they react to any changes in diet or exercise.
But again… just my opinion!