You can go a weeks without food and still survive. I took a NOLS course in the seventies and back then they had you pack out four hard days without food to show that you can. It isn’t pleasant, but shelter, warmth and water are what is vital for short-term and mid-term survival.
I know, and have fasted myself for over a week at a time and never thought about eating any of my dogs :) Seems like he was ill-prepared all around...