It’s difficult to say which of the functions of food and the nutrients that they contain are the three primary ones.
The nutrients in food serve as an energy source for the body. All metabolic processes require energy and this can be obtained from carbohydrates, proteins and fats.
Nutrients like proteins, minerals, fats, etc. are used to create the various parts of the body. For example creation of a major percentage of the bones requires the mineral calcium. Essentially every organ in our body requires proteins for it to be created for the replacement of portions that get damaged over time.
Nutrients like fat serve as an energy reserve. The body stores all the extra energy available in the form of fats which are used to generate energy when there is no other source or when the demand for energy exceeds the supply of energy in the form of carbohydrates.
Micronutrients like vitamins, minerals, various other substances like anti-oxidants, etc. are used to catalyze reactions in the body and play a role which is as important as that of the macronutrients in keeping the body healthy and allowing all the organs to perform their functions.
The most accepted concept in nutrition is that it serves three main functions:
a) To provide energy (through the consumption of carbohydrates, some fats, and protein).
b) To regulate body functions (through the consumption of water, fiber, lipids, carbohydrates, and protein, among others).
c) To help the body develop (through the consumption of minerals, vitamins, protein, and carbohydrates that aid in our body's different metabolic processes).
In conclusion, nutrients and food help nourish our bodies. They help our bodies become energized, as well as develop, grow, and stay healthy.
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