SUCCESS IN Nutrition

• Main Author: Pyke, Magnus (Author)
• Format: Book
• Language: English
• Published: London J. Murray 1975; ©1975
• Subjects: Nutrition
• Online Access: Click Here to View Status and Holdings.

 The science of nutrition is concerned with the various useful ingredients-or nutrients-of which foods are composed. It is concerned with the amounts of these nutrients which are required for the proper growth and functioning of the body, the way in which each one is useful to the body, and what happens when there is too little or too much of one or other component in a person's diet. Nutrition is thus a quantitative science; that is to say it is a study of the amount of each nutrient required by an individual. It is not sufficient to know that protein, for example, is a necessary constituent of the diet; we must know the amount required as well, for sometimes it is as harmful to eat too much of a nutrient as too little. Nutritional science therefore deals both with the amounts of each nutrient necessary for the functioning of the body and also with the amounts contributed by different kinds of food. Although the function and the required amount of each nutrient must be taken into account, it is also important to recognize that there may be quite wide variations between the quantities needed by different individuals. The human species is uniform to some degree and the nutritional requirements of men or women, old people or children can be assessed within certain limits of precision. Nevertheless, general statements concerning needs-for example, that 'children require a daily pint of milk' or that 'a glass of orange juice each day is necessary for health'-are not expressions of scientific truth, even if the contents of protein and calcium in the milk and vitamin C in the orange juice are expressed and interpreted in scientific terms. Two further points must also be remembered in studying nutrition. The first is that all science is merely the minimizing of doubt. Our knowledge of nutri tion has justified itself by the degree of command which it has enabled us to achieve over events by which, indeed, the correctness of our scientific know ledge has been verified. Understanding of the chemical structure of vitamin D, first elucidated in 1932, soon led to the prevention of rickets, the bone disease of children. Nevertheless, our understanding of the chemistry of vitamin D active substances in diet and as they occur in the body is still developing. Our nutritional knowledge is now considerable but, as always in science, there is certainly more to know.