I am referring to situations in which it is very likely that there will not be any food unless Shabbos leniencies are exploited. For example, if literally all my food is all in the fridge, but I know I left the light in--can I open it, if it's the only way I will eat Shabbos? Or if someone deliberately misused the blech, and all of the food we have is dependent on profiting from their melacha, may we still eat? Or if my [only] food is wrapped in something that would require extensive work to open, may I open it in order to eat?
The focus of my question is not on whether or how such a thing could possibly occur, but on where having no food at all on Shabbos would fall on the scale of illness and other extenuating circumstances that could lead to a loosening of (particularly rabbinical) strictures.
I imagine a situation in which there is no immediate threat to life or health, and in which--for the sake of interest--there is also no risk of not completing the positive mitzvot. In other words, one has enough wine for 1 kiddush, and enough for 1 kezayis (kebeitza?) of bread x 3 meals per person. But literally nothing else.