What is the essence of nutrition?

Food is the basis of life for most living things. In the process of eating food, the body receives the necessary organic (proteins, carbohydrates, fats, nucleic acids; other necessary micro and macromolecules) and inorganic (vital compounds, vitamins, metal ions and other elements) substances that it [the body] uses for its goals: cell regeneration / restoration of systems / homeostasis (constancy of the internal environment) / synthesis of substances and much more. Also, when food is oxidized, a certain amount of heat is released and ATP molecules are formed – they contain energy for the needs of the body.