Agriculture Reference
In-Depth Information
Figure
2.3.
Summer meal for Steve of corn on the cob. Each person will eat three ears, beef
roast, and salsa with ice tea to drink. (Courtesy of Steve Murphy.)
by desert. All four will be in about equal size proportions, although the meat and carbo-
hydrates may be in larger amounts in some cases, for instance, at the evening meal. The
meal will be finished with a dessert, commonly pie or cake, sometimes with ice cream.
The drink will also change with the meal. Breakfast will usually include juice and
coffee, lunch ice tea or a soft drink, and dinner ice tea.
2.2
INTRODUCTION
All people need food but the amount and type of food varies with age. Children need
enough food not only to maintain their body but also to provide energy and nutrients to
build new cells. There is also evidence that children need certain nutrients that adults no
longer need. Mature, nongrowing people, need only enough food to maintain their
body. However, there is more to nutrition than this. One food component cannot
totally substitute for another. That is, foods that primarily provide carbohydrates
cannot provide sufficient amino acids for the body, no matter how much a person
eats. Likewise protein-rich foods cannot provide all necessary fats for the body.
All types of components, except for minerals, can be used by the body to produce
energy, although not with the same efficiency.
Because of these needs, various organizations and government agencies have
devised recommendations as to the types and amounts of foods people need to eat to
remain healthy. Examples are recommended diets from the United States, through
the Food and Drug Administration (FDA), and from the United Nations, through the
Food and Agriculture Organization (FAO). The FAO dietary recommendations
are based largely on calorie intake and are shown in graphical form in Figure 2.4.
The FDA gives its dietary recommendations on the basis of amounts of various food
groups to be eaten as shown in Figure 2.5.
Both of these systems have advantages and drawbacks. The FDA system is easy to
understand and specific about the food groups to be eaten. However, it has the drawback
