well- when starting a new diet it doesn't matter how many pounds you lose the first week- and it doesn't matter that she's only consuming liquids as long as she's getting over 1000 calories and enough nutritional stuff. soup can do that just as well as a solid substance becasue once it goes into your body it's going to be turned mostly into liquid anyways and calories are calories. no- it can't lead to death if she's getting the right nutrition.