Our body needs all the nutrients in proper proportions for maintaining good health but a single food cannot provide all the nutrients in required proportions for the proper growth. Therefore our diet should contain all the nutrients in adequate quantity and in proper proportions by weight according to our body needs such that the diet becomes balanced. This makes a necessity of planning the meals and balanced diet. The balanced diet is one which contains different types of foods in such quantities and proportions that the need for all nutrients are adequately met and a small extra provision is made for extra nutrients as a marginal of safety.