The oft-repeated claim that fat cells fill up with water and then dump it has been pretty well debunked in recent years. Apparently there's no mechanism for them to even do it. But that was always just an overly-simplified attempt to provide an explanation for a phenomenon that thousands routinely observe. That the explanation has turned out not to be valid in no way means that the phenomenon isn't happening. It is -- we just need a better way of explaining it. The underlying mechanism still appears to be the same -- the body retains water even as fat is being lost and at some point the body dumps the water. The current thinking is that the body is attempting to maintain homeostasis and water retention is part of that. At some point the body loses that battle and readjusts to a new level, resulting in a purge of the bulk of the retained water. A lot more research needs to be done to nail down a more detailed understanding.

From a practical standpoint, it doesn't really matter. The Whoosh phenomenon, however well or poorly understood, is very real for many people that are losing weight (and it is not unique to LC by any means -- I experienced it each and every time I've ever tried to lose weight and succeeded in more than ten or twenty pounds no matter what diet/exercise program I was trying).

When I was trying to find some information on it a while back it was interesting to see the spin that the anti-LC sites put on the study that refuted the notion that fat cells fill with water. They talked about people going on LC for the sole purpose of experiencing the Whoosh effect. Huh? I've never heard of anyone saying that they wanted to try LC for the whoosh. They seem to be confusing the initial large weight loss with a whoosh, but that's absurd since a whoosh is, even by the fat-cells-fill-with-water model, by definition, something that can't happen until AFTER the fat has been lost. The initial weight loss on LC is NOT a whoosh, that is a different mechanism.

As for glucose being higher when on a ketone metabolism. This is the first time I've heard of this and it doesn't jive with my personal experience. But each person is different.