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DIET AND DISEASE
10.1 Introduction
Nutrition is concerned with food and how the body uses it. All nutrients must
be ingested, and most of them digested, before they can be assimilated and
used by the body. Carbohydrates, lipids and proteins are nutrients that are
required in comparatively large amounts. Others, such as vitamins, minerals
and trace elements, are also necessary but are required in much smaller
quantities. Water is also necessary to support life. Nutrients have a variety
of metabolic roles and are needed for normal growth, development and the
maintenance of health. The body can make some nutrients from others that
must be supplied in the diet; the former are nonessential, the latter essential
nutrients. Specific daily nutritional requirements are determined by a number
of factors and, indeed, vary throughout the life of any individual. The major
factors concerned include the age, sex, physical activity and the general well-
being of the person concerned and, in the case of females, menstruation,
pregnancy and lactation. Good nutrition is essential for health and the
prevention of diseases. Nutritional disorders may arise from a deficiency or,
in some cases, an excess of some component of the diet.
OBJECTIVES