Principle of nutrition

Food is one of the basic necessities of life. It is required for several purposes. If enough food is not taken, one feels hungry and dose not have the necessary energy to attend to our work. Food is required to supply the body-building materials necessary for an infant to grow into an adult to replace the daily wear and tear in tissues occurring in the course of normal living. Certain materials needed in small amounts by the body and which help to assimilate the food and keep the body mechanisms in proper shape and working order are also provided by food itself.
Optimum nutrition is essential for maintenance of good health. Nutrition of the body means the supply of essential nutrients in adequate quantities and in proper proportions to all the cells and tissues of the body so as to keep the structure and functions of the body in a sound state. This is affected by ingesting food and water, and digesting and assimilating the same. Diet is nothing else but a combination of different foods as they are available in nature. Such a combination is essential because there is no single food which will give man each and every nutrient in proper proportion required for nourishing the body cells. It is needless to say that for selection of a diet good for health, both the working knowledge of the basic principles of nutrition and the art of preparing food, are essential. For nourishment of the cells, the basic principles involved are:
1. Water,
2. Digestive end products of proteins, carbohydrates and fats,
3. Vitamins, and
4. Minerals.
Water:
Water forms about 70% of the body weight and is important constituent of all body cells. All the chemical reactions and processes in the body take place in the medium of water. Sufficient quantity of water should, therefore, be ingested daily. More water is required in summer than in winter. The rest will be discussed later.