Answer:
A food is something that provides nutrients. Nutrients are substances that provide: energy for activity, growth, and all functions of the body such as breathing, digesting food, and keeping warm; materials for the growth and repair of the body, and for keeping the immune system healthy. 
Carbohydrates - dietary fibre: Fibre 
Fats: To provide a concentrated source 
Proteins: To build cells, body fluids, antibodies 
Step-by-step explanation: