hte

With the above facts in mind, we will focus our attention upon the
hygiene of the important systems of the body. In selecting the following
topics, it is recognized that they do not cover the entire field. Our
effort has been to present the most important and fundamental topics.

HYGIENE OF NUTRITION

Satisfactory nutrition is fundamental to health. The individual must
have a reasonable knowledge of the physiological processes involved.
This should include familiarity with practical methods of determining
the food requirements of the individual; a working knowledge of the
composition and nutritive values of foods; and, a satisfactory under-
standing of the hygiene of the diet with some practical guides to
adequate nutrition.

1. Functions of Food in the Body

The functions of food in the body may be summed up under the following
heads:

a. To furnish energy
b. To build or repair tissues
c. To regulate body processes

&- Quantity of Food Requirements

The adaptation of the quantity of food intake to the actual needs of
the individual is the first step in assuring adequate nutrition. This
adaptation requircs the use of some unit of measurement common to
foodstuffs and the human organism. We have this unit in the calorie.

The actual amount of food intake required for a particular individual
varies with the:

a. Size and shape or body

b. Age

Cc. Sex

d. Degree of activity

e. Glandular activity

f. Efficiency of the digestive and assimilative mechanisms

A crude, but satisfactory, method of estimating the theoretical needs
of the individual is to use the age, sex and bodily activity factors
by the following formula: 7

Energy values based on activity
a. Light exercise 40-45 calories per kilogram of body weight
'"!

b. Vigorous exercise 45-50 " . " . .
Cc. Severe exercise 50~60 " " " " " "