Let's not promote being a nanny state/country..
Obviously everyone who partakes in the 40 hour famine knows they are going to be hungry and could have further complications.
It is the individuals choice as to whether they drop out early, depending on their circumstances.
I think it is good that kids/people get the opportunity to be passionate about something, even if it is just for a few weeks a year (to fund raise etc).
There are some great life lessons to be learnt in partaking in events like these.
Sporting events/marathons can be just as detrimental to a persons/child's health. So saying one is better then the other is silly.
OP I am glad your daughter was doing better. Obviously she would have reached the end by now. Good on her for sticking to something she believes in. We need our future promises to be able to do things like that!