n various bulletins.[76]

245. Wide and Narrow Rations.--When the amount of carbohydrates in a
ration is small in comparison with the protein, it is called a narrow
ration, while a wide ration is one in which the carbohydrates are much
in excess of the protein. When a ration contains 0.40 of a pound of
protein, 0.40 of a pound of fat, and 1 pound of carbohydrates, it has a
nutritive ratio of 1 to 4.8 and is a narrow ration. To calculate the
nutritive ratio, the fat is multiplied by 2-1/4, the product added to
the carbohydrates, and this sum divided by the protein. It is not
possible to designate accurately the amount of protein and other
nutrients that should be in the daily ration of all persons, because the
needs of the body vary so with different individuals. Hard and fast
rules governing the amounts of nutrients to be consumed cannot as yet be
formulated, as our knowledge of the subject is too limited. It is known
that both excessive and scant amounts are alike injurious. While the
appetite may indicate either hunger or satiety, it alone cannot always
be relied upon as a safe guide for determining the amount and kind of
food to consume, although the demands of appetite should not be
disregarded until it has been demonstrated beyond a doubt that it is not
voicing the needs of nature. There has been a tendency which perhaps was
a survival of the Puritanical ideas of the early days to stamp as
hurtful whatever seemed desirable and pleasant; as examples might be
cited the craving for water by fever patients, and for sugar by growing
children, which have now been proven to be normal demands of nature.

246. Dietary Standards.--As a result of a large number of dietary
studies and digestion experiments, dietary standards have been
prepared. Atwater in this country and Voit in Germany have proposed such
standards for men employed at different kinds of labor, as follows:

==========================================================================
|Protein| Fat|Carbo- | Fuel |Nutritive
| | |hydrates| Value |
---------------------------------|-------|----|-----------------|---------
| lb. | lb.| lb. |Calories| Ratio
Man with little physical exercise| 0.20 |0.20| 0.66 | 2450 | 5.5
Man with light muscular work | 0.22 |0.22| 0.77 | 2800 | 5.7
Man with moderate muscular work | 0.28