Diet plays a vital role in the maintenance of good health and in the prevention and cure of disease. In the words of Sir Robert McCarrison, one of the best known nutritionists, The right kind of food is the most important single factor in the promotion of health; and the wrong kind of food is the most important single factor in the promotion of disease."

The human body builds up and maintains healthy cells, tissues, glands and organs only with the help of various nutrients. The body cannot perform any of its functions, be they metabolic, hormonal, mental, physical or chemical, without specific nutrients. The food which provides these nutrients is thus one of the most essential factors in building and maintaining health. Nutrition, which depends on food, is also of utmost importance in the cure of disease. The primary cause of disease is a weakened organism or lowered resistance in the body, arising from the adoption of a faulty nutritional pattern. There is an elaborate healing mechanism within the body but it can perform its function only if it is abundantly supplied with all the essential nutritional factors.

It is believed that at least 45 chemical components and elements are needed by human cells. Each of these 45 substances, called essential nutrients, must be present in adequate diets. The list of these nutrients, include oxygen and water. The other 43 essential nutrients are classified into five main groups, namely carbohydrates, fats, proteins, minerals and vitamins. All 45 of these nutrients are vitally important and they work together. Therefore, the absence of any of them will result in disease and eventually in death. Research has shown that almost all varieties of disease can be produced by an under-supply of various nutrients. These nutritional deficiencies occur on account of various factors, including the intense processsing and refining of foods, the time lag between the harvesting and consumption of vegetables and fruits, the chemicals used in bleaching, flavouring, colouring and preserving foods and the chemical fertilisers, fungicides insecticides and sprays used for treating the soil.

Therefore, as a first principle of nutrition, one should insist upn whole meal flour and whole meal bread and avoid the white stuff.

Research has also shown that diseases produced by combinatins of deficiencies can be corrected when all the nutrients are supplied, provided irreparable damage has not been done. A well-balanced and correct diet is thus of utmost importance for the maintenance of good health and the healing of diseases. Such a diet, obviously should be made up of foods, which in combination would supply all the essential nutrients.

It has been found that a diet which contains liberal quantities of (I) seeds, nuts, and grains, (ii) vegetables and (iii) fruits, would provide adequate amounts of all the essential nutrients. These foods have, therefore, been aptly called basic food groups and the diet contains these food groups as optimum diet for vigour and vitality.