That does happen, but the body is very good at making sure that levels of blood-glucose are maintained. If it is not, as in the case of diabetes, then very bad

That does happen, but the body is very good at making sure that levels of blood-glucose are maintained. If it is not, as in the case of diabetes, then very bad things happen. Things like a diabetic coma. As other commenters have said, absent any extreme weight loss or undiagnosed metabolism disorders like diabetes, there is nearly no chance that glucose burn-out occurred in an otherwise 'healthy' person. We may all be wrong, or missing some key information, at which point I look forward to the cuhbbyEmu video on it.