Certainly that turned out to be the case with me -- I stalled at a high weight for two years' total time on very low carb, and only by ditching the plant matter completely could I restart the weight loss. And a lot of that has gone in fits and starts; overall, it's taken me nearly four years of VLC and ZC combined to lose 70 or so pounds.

There are a couple of people I know of, though, for whom even so-called
"zero-carb" doesn't seem to work; they don't lose weight and remain ravenously hungry, putting away enormous rations of meat at each meal. It's as if the body needs a lot more healing before it's ready to surrender its fat stores (I'm partial to the theory that obesity is actually a protective response, like fever or inflammation, that can, of course, become a threat in its own right if the state of emergency goes on long enough). A great deal more research will need to be done into what the issue(s) is/are for people who can't lose.