Most Helpful Guy
Recommended daily recommendations aren't "average".
They are what you should eat to avoid dietary deficiencies and subsequent impacts on your health.
So if you don't have much of fat reserves to speak of, and you eat less than that you ARE eventually going to lose muscle mass, and slowly but surely develop complications that would result in organ failure and death.
That being said, if you got stranded on a deserted island.
You could get way more than that by just eating plants and tree bark.
Humans can eat a lot of things that animals can, it isn't going to be the most palatable or digestible but a lot of things have nutritional values.