ain

4, Classification of Foods: Food compounds have been classified into groups
according to their chemical composition and their physiological action.
Most foods belong in more than one class, though usually they have one
agominant function or value.

 

5. Food Groups: The food compounds and principles essential for human life
may be classified into the following groups:

a. Water e, Carbohydrates

be Inorganic salts f. Oxygen

c. Proteins g. Vitamins

d. Fats h. Food accessories

6. Food Values: Our estimate of the value of various foodstuffs has been
secured through three main standards of measurement:

a. Chemical: For many centuries the sole wit of measurement was secured
by chemical analyses.

b. Physical: Values have been attached to foods, based upon their ability
to produce heat, measured in heat units,
Unit of measurement--Calorie (large) the amount of heat necessary to
raise 1 kilogram of water 1° centigrade.

c. Biological: The newer values are based upon carefully controlled feed-
ing experiments on animals.

7. Minimum Essentials: While the exact chemical composition and physiologi-
cal action of the numerous substances used for food would be useful and
desirable, it is not necessary in order to intelligently sclect a well
balanced dict to fit your peculiar needs. .

 

The following facts, however, are considered the minimum essential know-
ledge about each one of the food groups as guides to adequate nutrition:

ae Function of group in body.

b. Source from which it can be most cconomically secured
physiologically .
financially

c. Nuantity required by body.

d. Quality producing best results,

(Note--Student is expected to look up the above facts about each one of
the groups of foods enumerated above.)

MECHANISMS OF DIGESTION AND ASSIMILATION

1. Preparation of Food

 

To understand the varied aspects of the preparation of foods is one of the
essential foundations of a nutrition program, This may be considered from
the standpoint of its crude preparation by plants and animals; its refine-
ment and distribution by man; and its physiological preparation by the body.

ae Plant: Assembled by plants from the air and soil. :
b. Animals: The making over of plant life into animal tissue.
e. Production, transportation and distribution by man.

d. Domestic: Preparation for consumption.

€. Physiological preparation: digestion,