Among the six nutrients in the three staple foods, protein, fat and carbohydrate are the main contents.

Every100g:

White flour: protein:12.0g, fat: 0.8g, carbohydrate: 70g.

Corn flour: protein: 8.5g, fat:1.5g, carbohydrate: 78.4g.

Rice: protein: 7.5g, fat: 0.5g, carbohydrate: 79g.

These six nutrients include carbohydrates (sugar), oil, protein, vitamins, water and inorganic salts (minerals).