Balanced Diet: Our food consists mainly of proteins, carbohydrates, lipids, vitamins, and minerals. The value of a food is expressed by dietitians in the form of their heat value by the unit calorie. A calorie is the amount of heat required to raise the temperature of 1 gram of water by 1 degree centigrade. When metabolized inside the human body 1 gram of protein produce 4.1 calories, carbohydrates give 4.1 calories and fats give 9.3 calories.
While prescribing a standard or balanced diet it should be taken into consideration that a balanced diet must contain a minimum amount of energy, i.e about 3000 calories for a man of moderate work.
A variety of food must be included in the proper portion; age, sex, work and conditions of health of the persons concerned and climate of the living place should be taken into account. The tastes and desires of the person should be considered.