The calories and energy contained in food are not the same concept. Energy is the basis of nutrition and the first nutritional attribute of food.

The difference between energy and heat is that the scope of energy is larger than that of heat. Energy includes heat, kinetic energy, internal energy, etc. Heat only refers to the energy released or absorbed during the process of releasing or absorbing heat. The only connection between the two is that heat is a changing amount of energy. The calories and energy contained in food are not the same concept.

Calorie is the energy consumed by the human body every moment. This energy is provided by thermogenic nutrients in food, such as protein, fat and carbohydrate. Food energy refers to the energy released from food used throughout the entire digestion process in the body to maintain various life activities in the body and perform external work.