well according to doctors and biologist we need nutrients to survive that's why we eat but whether it is true is a different matter entirely.
According to research on the human body, we adapt to what ever we take in the body over time.
so if we start eating a known poisonous food with the believe that we will not die, we will not. In this case our bodies will adjust to it over time. SO nutrients work because we believe they will. if we change our believe, they wont
if we all accept and believe that stones can be cooked as protein, it shall be so