Food is one of the most basic requirements of life. Food supplies us with energy. It is also required for growth and maintenance of the body. It also protects us from diseases.

Components of food
Food contain various chemical substances required by our body. These chemical substances are called nutrients. Our body needs some of these nutrients in larger quantities ad some in only very small quantity.
These nutrients can be broadly grouped into the following seven classes.
1. Carbohydrates    2. Fats            3. Proteins        4. Vitamins
5. Minerals             6. Water          7. Roughage

Balanced Diet
•    A balanced diet is one which provides proper amount and proportion of fats, carbohydrates, proteins, vitamins and minerals, needed for the growth and maintenance of the body. A  balanced diet should have three main qualities :
1.     It should be rich in essential nutrients like minerals and vitamins.
2.     It should provide the exact amount of raw materials needed for growth, development, repair and replacement of body tissues.
3.     It should provide the right amount of energy required by the body.

Classification of food
•     Food can be classified under three different categories on the basis of its functions:
(i) Energy giving food : Carbohydrates and fats, eg. cereals, sugars, oils, etc.
(ii)  Body building food : Proteins, minerals and fats, eg. pulses, beans, milk, fish, etc.
(iii) Protective food : Vitamins &  minerals, eg. vegetables, fruits, milk, etc.