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MICROCOPY RESOLUTION TEST CHART
MICROCOPY RESOLUTION TEST CHART
or
NATIONAL BliREAU OF S1ANDARDS·1963·A
NATIONAL BUREAU
STANDARDS·1963·A
======:=~~=111~~======~
BULLETI~
10s~llWJJ~
1929
k" ,
:~O::GRICULTURE
r
c.
No.
TECHNICAL.
JANUARY,
UNITED STATE:
WASHINGTON,D.
-
.,'
A SHORT METHOD OF CALCULATING ENERGY, PROTEIN, CALCIUM, PHOSPHORUS~ AND IRON IN THE D1ET By EDITH HAWI.EY
Senior Food Eronomist, Eoonomics DW£ston, BurOOlU of Home Economic8
CONTENTS
l
(
l.r
Earl;!' food Investigations ________ _
FOud surveys of A=Ican famIlIes__
Usual method of calculatIng energy
and nutrients of the dleL_______
Shc.l't methods used by other Investigators in calculating energy, protein, and fat in dietarJes_______ _
Short method of calculating energy. protein.
calclum, phosphorus,
and_
_____________
iron
In the
dle~
Page
1
2
4
Page
How to use the short-cut method___
Foods not illciuded in the short-cut
method________________________
EvaluatIon of the short-cut method_
Summary and conclusions________
Literature clted________________
9
10
11
19
19
-
,
/) G
EARLY FOOD INVESTIGA,TIONS
I;:
Since the beginning 01 history much interest has centered around
the food habits of mankind. The earliest records are contained in
the laws of primitIve people prescribing more or less rigid rules of
diet. Many books of travel, ancient and modern, reflect this same
interest in the descriptions of the food habits of foreign peopJes.
Though these may give a good picture of the type of food eateil in
various countries and methods of preparation, they are in the main
based on opinions and impressions gathered hastily and oftentimes
colored by prejudice. At best this is purely qualitative information.
To-dAy the demand is for data on food habits that can be expressed
quantitatively.
Interest in quantitative food data began to davelop somewhat over a
hundred years ago in connection with standard-of-living studies in
Europe. Since then a great deal of material has been collected in the
United States as well as in other countries, but analysis of the data in
terms of welfare is almost negligible.
en Eden (3)1 in 1797 published a description of the life of about 100
It~oor families in England. The amount which each family expended
~or six (,r seven food groups is shown. .A.bout the middle of the
~
Itr~~~I------------------------------------------------------OJ.1Jleference Is made by italic numbers in parentheses to .. Literature cited," page 19.
e::: \ 21810·-29-1
1
c::r:
;E
~
I
2
TECHNICAL BULLETIN 105, U. S. DEPT. OF AGRICULT~E
l
nineteenth century LePlay (6) described in great detail the way 54
workingmen's 1amilies in various countries lived, and gave informa­
tion on the amount and value of the food consumed. Ducpetiaux (93)
about the same time reported on th~ standards of living, including
amount expended for various foods, for 199 Belgian families taken
from three income levels--dependent, self-supporting but saving noth­
ing, and self-supporting with surplus. In all of these reports each
family was treated as a unit. Eden and LePlay made no attempt to
classify or to summarize their data. Ducpetiaux, on the other hand,
made 1m elaborate classification of the expenditures of the families
studied by him but did not summarize the material.
In 1857 Engel (4-) l as head of the Saxon Statistical Bureau, pub­
lished the results of a study on production Ilnd consumption in
Saxony, in which he used 235 cost-of-living records recently published
by Ducpetiaux and LePlay. This is the first careful statistIcal study
of such material. These early studies have been followed by others
of the san:,- kind and more oJ' leSt:) extensive in scope in practically
every European country.
FOOD SURVEYS OF AIUERICAN FAMILIES
_IIJII
Cost-of-living studies for families were begun in the United States
about 15 years after the Saxon report. In 1875 the Massachusetts
Bureau ol Statistics of Labor (7) reported an investigation of the
cost of living of 397 workingmen's families in Massachusetts and a
little later began a study of the dietary habits of workingmen's fam­
ilies (8). During the 50 years that have elapsed since that work ~
was started, a mass of information concerning food habits has become ,
available.
Dietary studies differ in certain respects from cost-of-living and
standard-of-living studies. As the name indicates only the food
consumed by an individual or a group is investigat.ed in dietary
studies, whereas in cost-of-living and standard-of-living ~tudies not
only food but all of the items that go to make up the living are
included. The methods commonly used in collecting information
pertaining to food habits for the two types of studies differ. In
mo.st dietal'y studies the actual quantity ni food consumed. during
a stateti time, usually one or two weeks, is weighed and recorded.
It is assumed that food habits are about the same from week to week,
and the results presumably give a good picture of the food consumed
at least during that season. In studies of standllrd or of cost of
living, on the other hand, the quantity and cost of the food coru;umed j
uuring the preceding year is generally e!'timated. Figures collected ~
by thIS method contam more inaccura )i~S than those obtained by
careful dietary studies, but they have the possible advantage of
including sea.sonal differences in food consumption. This method
also lends itself more readily to -the collection of a larger number
of food recordr::.
About 80 studies of food consumption and cost, covering from 1 to
25.440 families, have been made in the United States since 1875. l
From them information on food habits is available in more or less
detail for 75,283 families. For approximately 5 per cent of these ,
families dietary studies Tere made, and for 95 per cent the food
SHORT METHOD OF CALCUL..\ .TING NUTRIENTS IN THE DIET
3
information was gathered as part of cost-of-living or standard-of­
living investigations. In most cases some analysis and summary
have been made of the food data; but, considering the wealth of
material available, the information that has been gleaned from it
is scanty.
.
The extent of analysis of these food r"ecords is ~hown in Table 1.
The average cost of food per family has been calculated in 32 of the
studies, or 94.7 per cent of the total !lumber of records collected.
In 41.3 per cent 'of the tot..l the records were analyzed to determine
the average quantity of various foodstuffs .consumed. Such calcu­
lations were made for only $) or 10 foodstuffs in some of the investi­
gations, wher"eas in others they were carried through the entire
diet. The amount of energy and protein, or energy, protein, and
minerals yielded by the average diet of the group was calculated in
four studie.s, which include only 3.9 per cent of the total number
of records collected: Some aspect of the average diet has therefore
been studied in many of the investigations, but for purposes of
popular education in nutrition it is necessary to know whether the
average is typical of one group or whether the deviations point to a
nutritional cvndition different from that L'ldicated by the average.
This necessitates careful stndy 'nf individual family diets and has
been given to only 1.2 per cent of the 75,283 records collected.
1.-E:ctent of analysi8 of food, records from, 75,288 American families
made by'-nvcstigators wha collected< then~ during the period 18"15 to 1928
TABLE
Factors studied
Number
Analysis of specified fac· or studies
with
Records analyzed
tor according to average
diet of grOUD or to diet of =:Z~d for specified factor
lndividuallamily
for speci·
fied factor
Cost.... ....................................... Ave..aga........____..__•__
Quantity of various roodstuJIs consumed ............do..........____.......
:Energy and protein .................................do....................
Energy, protein. minerals ...........................do...____..__.......__
Energy, protein, cost........................... Individual................
Energy, protein, minerals, cost......................do...................
32
11
2
2
29
6
Number Per unl
71, SOl
31, 119
2,600
330
565
871
9·1. 7 41.3 3.5 0.4 0.8 1.2 Probably the analyses have in most cases been adequate for the
problems the investiga.tors were considering, but to-day questions
are being asked for which there are no ready answers obtainable from
these studies. In 1920 Pearl (.9) published figures showing the aver­
age American diet for the years 1911 to 1918. Nutritionists aHd wel­
fare workers ask whether there are significant deviations from this
average diet; and if so, among what people they occur and what are
~heir causes. Certain students of the agricultural situation ask ' whether production and consumption of the main foodstuffs can not
be made to balance in the United States. Economists interested in
the welfare of the consumer want to know whether such a production
program is conducive to the health and well-be.ing of the consumer.
There are local differences in food ha.bits. Distributers want to know
what these differences are in order to eliminate waste in marketing.
The questions asked by the economists and business men could in
many cases be answered by consumption figures derived from produc­
_
.
4
TECHNICAL BULLETIN 105, U. S. DEPT. OF AGRIOULTURE
non, export, and import statistics. But when changes are groposed;
the nutritionist and welfare worker ~mmediately ask, 'Are the
changes that you propose in the interest of the consumer'S: w"lfare ~ "
"Will the quality of his diet be improved or at least maintained at
its present level ~" In order to answer these questions it is necessary
to consider not only the hundred or more foodstuffs as they are re­
ported but 5 to 10 of the nutrients of which they ar~ composed. This
leads the investigator into long and tedious calculations. If, in addi­
tion to information on the average diet~ a knowledge of the nutri­
tional value of the food consumed by the individual families is de­
sired, a formidable amount of statistical work becomes necessary.
USUAL METHOD OF CALCULATING ENERGY AND NUTRmNTS OF
THE DIET
.According to the present knowledge of nutritive requirements, food
is recognized as containing at least 20 elements or combinations of
elements essential for normal growth and development. These in­
elude 10 minerals, 6 unidentified substances called vitamins, water,
and 3 energy-yielding food constituents-fat, carbohydrate, and pro­
tein. A complete analysis of a dietary would include a study of all
the food constituents, but f(''';" various reasons this is not done in actual
practice.
Of the 10 minerals that are required, according to present knowl­
edge only 4--calcium, phosphorus, iron, and iodine-are likely to be
furnished in insufficient amounts in the diet. For the first three,.
average composition figures are availaLle for most foods, and con­
siderable study has been made of the amount of each required for
grQwth and maintenance. They are therefore commonly included in
an analysis of a dietary. lodme, on the other hand, has not been
studied sufficiently to justify its inclusion in a dietary analysis.
Nor is it yet possible to measure vitamins quantitatively, since they
have not been isolated as chemical individuals. .The relative values
of many foods as sources of vitamins, however, have been ascertained
through animal experimentation, and the amount needed in the nutri­
tion of these animals is fairly well established. In setting up vitamin
standards for man the best that can be done ~\!.t present IS to suggest
that the foods which are especially good sources of the various vita­
mins be used to furnish a liberal proportion of the energy of the diet.
Since the danger of water deficiency is so slight its inclusion in a
dietary analysis is deemed unnecessary. Energy, measured in calo­
ries, is most commonly used as an indication of the nutritive value
of the diet. This is sound, for without enough food to meet activity
demands the bodv will use up its own substance to keep itself going.
When this occurs the body's requirement of the other constituents IS
increased. 'rhe actual amount of fat and carbohydrate in the diet is
sometimes ascertained in addition to total energy. But since experi­
ments have shown that within wide limits the human body is able to
use either of these nutrients advantageously for energy, their detailed
study in a dietary analysis seems unnecessary. Protein, on the other
hanel, is important, not only for the enersr it yields, but even more
for growth and repair and IS usually studIed separately.
The analysis of a dietary therefore commonly involves the deter­
mination of energy and four to six food constituents. Such an analy­
i
j
~
SHORT METH(lD OF OALOULATING NUTRmNTS !N 'rHE nmT
5
sis is usually made by finding the amount of energy· and nutrients
furnished by each food consumed and then totaling them to 9,scertain
the amount furnished by the total diet. These fi~ures are compared
with the estimated need of the individual or the family to determine
whether the di<';!t, according to present standards, is adequate for
growth, maintenance, and activity.
When the food consumed by a family is studied by this method for
energy, protein, calcium, phosphorus) and iron content, it necessitates
the multiplication of the number of grams or pounds of each food­
stuff used, by five factors. If fat and carbohydrate are also in­
cluded in the analysis the number of multiplications for each food­
stuff is increased to seven. Since a family dietary contains on the
average from 45 to 55 foodstuffs analysis by the item-by-item method
means approximately 250 to 350 multiplications. In this bureau
with equipment suitable for such work, the calculation of the nutri­
tive value of a dietary by this method requires about two and a half
hours. If the num.bel' of records to be. analyzed. is large, the time
needed for such a study makes it almost prohibitive.
SHORT METHODS USED BY OTHER INVESTIGATORS IN CALCU.
LATING ENERGY, PROTEIN, AND FAT IN DIETARIES
.
,
I
Because the item-by-item method of calculating tlie nutritive value
of a diet is time consuming and the need of a quick method of evalu,.
ating a dietary was recognized, two shorter methods have been
proposed.
Hunt (5) was the first to suggest such a possibility. In 1918 she
,published a plan by which the amourtt of energy and protein in a
~iet could be quickly estimated. According to her method the foods
are divided into five. groups, namely, vegetables and fruits; protein;.
rich foods; cereals, bread, an~ otl~e~ bak~ry goods; swe~ts; I1:nd fatty
foods. Each of these groups IS dIVIded mto two subgroups, .caUed ~
and 13, to provide primarily for energy .difi'erences.·· Energy values
are assigned to each group arid protein vall!-es to all ex?e,Pt the swee~s,
In Subgroup A are classed the foods havmg compositlon~figul'es ill
close agreement with these values, and in Subgroup B are li~ted those
that differ widely from' those values. The total weight of the foods
in Subgroup B is mUltiplied by a weight factor that brings it to
a basis equivalent with the foods of Subgroup A. The result is
ndded to the weight of the foods in Subgroup A. This total is then
mUltiplied by the values for energy ar protem or both. The results
of these calculations for the 5 main groups of foods can then be
quickly added to find the energy and protein value of the entire diet.
For example, under vegetables and fruit;::; are the Subgroup A,
which includes fresh and canned vegetables and fruits, and the
Subgroup B, those that are dried. In order to find the nutritive
value of all the fruits and vegetables used, the total weight of the
foods in Subgroup B is multiplied by 6 and this value is added to
the weight of foods in Subgroup A. To determine the energy yalue
of the foods in this group, the total number of pounds given
by the above calculation is multiplied by 250 calories, and to find the
protein value expressed in pounds the total weight is divided by 70.
Values for the other four groups are obtained in a similar manner,
and the total for the entire diet is thus quickly found.
6
TECHNICAL BULLETIN 105, U. S. DEPT. OF AG;&:rCULTURE
RlUlt cited three dietaries by which she tested the accuracy of her
method. In all cases the energy values agreed within 2.5 per cent
with the figures obtained by the item-by-item calculations. The pro­
tein values showed greater fluctuations, but the errors did not exceed
6 per cent. Hunt pointed out that the chance of accuracy was greatly
increased by a. varied diet, a fact that enhances the value.of the
method, because it is for the diets containing a wide variety of food­
stuff's that a short-cut method is most needed.
T".,e second method for simplifying such calculations was proposed
by Rose (10) in 1920. His method provides for ascertaining the total
energy value as well as the protein and fat. in the diet directly 'and
the percentage of carbohydrate by difference. It is more elaborate
than Hunt's and requires somewhat more time for computation. On
a wide variety of diets it would doubtless give greater accuracy be­
cause a greater range of factors is used in rendering the weights of
the foods equivalent.
Rose diVIdes the foodstuffs into seven main groups-namely,
cereals and cere!).! products, dry legumes and shelled nuts, ve~etables
and fruits, ce:;::bohydrates, iats, foods rich in fat and protem, and
animal p!'oducts exclusive of whole milk and fats. The cereals and
cereal products are arranged in six subgroups, but eight correctional
factors are assigned to each of the constituents1 energy, protein,
and fat, for the equalization of the various SUbgroups. This is
the method carried out in all of the main groups. Dry legumes and
shelled nuts consist of 2 subgroups and 3 correctional factors for
each constituent; vegetables and :fruits. 6 subgroups and 9 correc­
tional factors each i carbohydrates, 2 subgroups and 2 factors to cor­
rect for total calorles; fats, 2 subgroups and 3 factors to correct for
total calories; foods rich in fat and protein, 4 subgroups Rnd 7 fac­
tors each to correct for total, protein, and fat calories; and animal
products exclusive of whole inilk and fats, 11 subgroups and 12
correctional factors each.
Energy values for total calories, protein, and fat are assigned to
each of the seven main groups. After multiplying the various food­
stuffs in a given group by the correctional factor to render the weights
of the group e9,uivalent to one another, the total weight for the
group is multiplIed by the energy values assigned for the three con'"
stituents to find the value of the group. Each of the seven groups
is treated in this way, and the sum of the values obtained gives the
.
total, the protein, and the fat calories of the diet. .
In evaluating his method RoSe compared the results obtained by it
with those obtained by the item-by-item method and with those by
Hunt's method, but he does not estimate the degree of accuracy that
may be expected by the use of his short method.
~
I
SHORT :METHOD OF CALCULATING ENERGY, PROTEIN, CALCIUM.
PHOSPHORUS, AND lRON IN THE DIET
When the task of studying some 3,000 records of food consumption
of farm families recently arose in the Bureau of Home Economics, the
need of n. quick method of computing nutritive value was again em­
phasized. The methods of Runt (5) and Rose (10), described above,
provide only for the calculation of the energy, protein, fat, and carbo­
l
SHORT :METHOD OF CALCULATING NUTRIENTS·IN THE DIET
7
hydrate of the diet. Since the three minerals-calcium, phosphorus,
and iron-are so often deficient, it seemed desirable to include these
minerals.in the analysis of the farm diet. A third short-cut method of
computing a dietary was therefore develo:ped.
.
This method provides for the calculation of the energy, protein,
calcium, phosphorus, and iron in the diet, and is designed for foods
as purchased. It should give satisfactory results when used in the
analysis of any varied diet, either for family or institution, if it is
based on raw foodstuffs as they are usually purchased. In most
dietaries that have been analyzed by the item-by-item method the
weight of the foodstuffs consumed has been given in grams. Like the
methods of Hunt and ...10se, this short-cut method provides for the
use of the pound instead of the gram as tIle unit of weight. It is also
based on a principle similar to theirs, and the classification of foods
follows the same general lines; that is, the common groupings are
used, fruits and vegetables, fats and sugar, meat, milk, and cereals•.
Fruits and vegetables are divided into four groups, and cereals into
two: The classification of 133 foods is shown in Table 2; and the
factors for use in adjusting the nutritive value of the foods, to corre­
spond with the nutritive value of the group in which they occur, are
shown in Table 3. The foods are arranged in each group in the order
of decreasing calorie value.
2."'-cllJ88ification Of 133 foods used in· shorl-cut methotl develop~ in,
Bureau of Home Economics for analyzing a diet, 1xI.wd on. foods as purcha.~etJ
(.:1. P.) e07Jcept token, specified a8 edible portion, (E. P.)
TABLE
Group 1:
Figs, dried.
Citron, dried.
OUves, g r e e n,
pickled.
Raspberries.
Figs, fresh.
Parsnl~.
Carrots.
Strawberries.
Turnips.
Okra.
Rutllbagas.
Clams, In shell.
Chard.
Caullfiower.
Kobl-rabl
(E.
P.).
Grallefrnlt.
Oranges.
Lemons.
Rhubarb.
Lettuce.
Celery.
Group 2:
Pecans, In shell.
Apricots, drlelJ.
Potatoes, sweet.
Plums.
Grapes.
Cherries.
Apricots, fresh.
Penrs.
B1ackbl'rries.
Currants, fresh.
Onions.
Pl'aches.
Apples.
Beets.
.
Eggpiant(E.P.).
Peppers. green.
Tomatoes.
RadiShes.
Group 2-Contd.
Muskmelon.
Squash.
Cucumbers.
Pumpkin.
Watermelon.
Group 3:
Coconut, dried.
Currants. dried.
Prunes, dried.·
Raisins.
Dates, dried.
Tapioca.
Apples, dried.
Honey.
Potatoes.
Bananas.
Dandellon
greens.
Mushrooms.
Clams (E. P.).
Oysters (E. P.).
Beans, string.
Spinach.
Cabbage.
Asparagus.
PineapplE' (E.P.).
Cranberries.
Group 4:
Peas, dried.
Beans, drIed.
Beans, kidney,
drIed.
U!ntlls, dried.
Beans, lim a,
dried.
Chestnuts.
Eggs.
Peas, green, In
pods.
Beans, lim a •
green, In pods.
Corn, fresh.
Grou£a~
Oils, table.
Butter.
Margarlns.
Jelly.
Sugar.
Group 6:
Pork, salt.
Bacon.
Sausage.
Ham, smoked.
Goose.
Mutton.
Pork.
Beef. corned.
Lamb.
Turkey.
]kef (A. P.). Beef (E. P.).
Beef. dried.
Fowl.
Liver.
Veal.
Group 7:
Cheese, Ameri­
can.
Cream, 40 per
cent milk fat.
~lI1k. condensed.
Cream, 18.5 per
cent milk fat.
Milk, whole,
fresh.
Milk, skimmed,
fresh.
Buttermilk,
Whey.
Group 8:
Peanuts, in
shell.
Flo u r , buck­
wheat.
.Group _8-Colltd.
Walnuts, Enlt­
Ush, in she~
Fish containing
more than I)
per cent fat.
Cheese, cottage.
Almonds. In
shell.
Fish containing
less than I)
per cent fat,
Group 9:
Cocoa.
Chocolate.
Bran, wheat.
Cowpeall, dried-.
Oatmeal.
Flour, graham.
Wbeat,
shredded.
Flour~
wholewheat.
Corn mllaL
Flour, rye.
Hominy.
Bread, graham.
Bread,
wholewhl'at.
Bread, rye.
Group 10:
MacaronI.
Flour. white•.
Crackers.
Furlna.
Rice.
Coconut, fresh,
In shell.
Bread, white.
Breall. Boston
brown.
....
8
TEOHNICAL BULLETIN 105, U. S. DEPT. OF AGRIOULTUR:E
Reference to Tab~e 3 shows that one factor is used for adjusting
the protein, calcium, phosphorus, and iron values of each food to
meet the four values assigned to the group. Such a limitation natu­
rally makes the classification of 133 foods difficult. In meeting this
problem the first step was to find the amount of nutrients yielded by
1 pound of each of the foodstuffs. This calculation showed a range
in the 133 foods of about 90 grams £oi.' protein, 1.4 grams for cal­
cium, 2.3 grams for phosphorus, and 0.04 gram for iron. A few
foods that were outside these limits were disregarded at this point.
In order to classify the foods according to their importance they
were arranged in 10 groups for each of th~ four nutrIents, and the
groups were numbered from low to high. A food, for instance,
might be in Groups 1 and 2 for the four nutrients, being low
in all of the constituents. Or it might be in Group 7 for protein,
2 for calcium, '{ for P~\'.\sphorus, and 8 for iron, being therefore a
food rather high in protein, phosphorus, and iron, and low in
calcium.
On the basis of this classification 10 groups were defined as fol­
lows: (1) Foods that are relatively better sources of calcium than
of protem, phosphorus, and iron; (2) foods in which all of the
nutrients are of about the same relative importance; (3) foods in
which iron is of relatively more importance than- the other three
nutrients; (4) foods inwhich calcium is relatively low and the other
three nutrients high; (5) foods that are lacking or practically lack­
ing in the four nutrients; (6) animal foods in which calcium is rela­
tively low, protein high, and phosphorus and iron intermediate; (7)
foods in which calcium is relatively high, iron low, and protein and
phosphorus intermediate; (8) foods In which protein and phos­
phorus are relatively high and calcium and iron low; (9) vegetable
foods in which calcium is relatively low, protein high, and phos­
phorus and iron intermediate; and (10) foods in which protein is
relatively higher than the other three nutrients.
The foods were classified. on this basis. During the period of test­
ing the method, however, changes were made when it was discovered
that some of the foods as they stood tended to invalidate the results.
It was found that some foods could not be satisfactorily grouped; sO
they will need to be calculated separately when they occur in the diet.
Others, in the prOCess of testing the method, were shifted from one
group to another in order to overcome the difficulties that arose.
After the foods had been classified, nuh'itive values were assigned
to each group. Thel'le are shown in Table 3 under Nutritive value
of groups per calorie-pounds and protein-mineral-pounds. In
Group 1 the protein and mineral values are based on the vegetables
that play an important part in the diet; namely, carrots, turnips,
lettuce, celery, and parsnips. The energy value of many of the
vegetables in the group approximates 150 calories per pound. Dried
figs and citron, on the other hand, yield about ten times that amount
of energy. Because of this wide difference and because 300, or
twice the energy value of the vegetables, is an easier figure to use,
this energy value is assigned to Group 1. A similar adjustment is
made in Group 2. The protein and mineral values assigned to
the group are based on the composition figures of sweet potatoes,
but the energy value is one-half of that yielded by sweet potatoes.
",
TABLE
~.
..,
;,
3.-F'or·m for calculating the nutritive value of the diet, showing calorie and protein-mineral factors for 1{18 foods and energy. protein, calcium, phosphorus, and iron values for each group
Equivalent
F-"'-I
Equivalent
N n...
'""Uve valne or groups per ,........
_T.".
Equivalent
,",,"'lO'
weight
,.,-ponnds an d proteIn-m Inoral-pounds
weight
Factors!
weight
Quan- , __---,.___ 11
~~·I--.---II
---.----~~.I---._--_1I--------_.I----.-----~--.----.·--~~--.--t1ty ,­
\
con­
Food groups
con­
Food groups
Proteln­
Proteln­
sumed
CalorieFood
groups
Calorie
OalorieFood
groups
Cal""'"
mmOcobsned.-) Calorieo:""p
Energy Protein
Cal· Phos­
Proteln- Bumed
min·
Obs.) ~~
Calorie mln­
Calorie mIn- (Ibs.) Calorie~
~~
--~
~~
~~~
pounds ~.
~
pounds
pounds
pounds
eral
pounds
_ _ _ _ _ _ _ _ I----------lil~--------I---------·II------------------11-------1-----------1--1------.-Equivalent
weight
Factors 1
flo
Fartors I
, _ _~_ _I Qaan· , _ _-:-_ _ 11
,tity ,-
~::~_~
Figs, drled__
_____________ l
OItron, drled---------------------l
5.0
5.0
Strawberrles_____________________
TO~_lps
___--_-_-_-__--_:_-:-__--_-_-_-_-_-_-__--_-_-_-_-_-_
.... u
Rutabagas_______________________
Clams, in shelL__________________
Ohard_________________._________
Oauiffiow&_____________ .________
Kohl.rabl (E. P.)________________
.5
.5
.5
.5
.5
.5
.5
.5
P~~-
drd;~-:-------------
5.0 ________________________ \ 0C'oconur'
1.0 ________________ ________
urran s, rl
_________________
~~iliTh~==:~1~~~~3 i:j tl ~~~~f==I~~ffi~: m==~~ ~~~~m~~~~~i
8~~~~::::::::::::::::::::::::
:g5
Lemons
f~~~:~~==::=:=:=:=:=:=:=:=:::=:
:~
Celery.__________________________
.2
________ ________ ________ Honey__________________________
________________
-------- 1 Bananas._______________________
Potatoes___________ ••__ ••_._.___
________________________
___________. ___ • ________ Dandelion green\l ..______________
________ ________ ________ Mushrooms_____________________
________ ________ ________ Clams (E. P.)___________________
1.7 ._______ ________ ________ Oysters (E. P.) _________________
1.0
1.0
1.0
1.0
6.0
3.0
1.7 ________ ________ ________
Beans, strIng____________________
:g :::::::: :::::::: :::::::: ~~~~~~e::::::::::::::::::::::::
A.spnragus
6 t
1: gI:::::::: ::::::::=::::::: t~:~~1J~::~:~=====:::::=::=:
1. U ,____________________ • ___
~~i~. sum(~bnSe.·)d
~:~:~_~
Pr~~~-
3.0
1.0
2.0 ________ ________ ________
2. 0 ________ ________ ________
Pork, RnIt __
..___________
Bacon__________________________
3.5
2. 6
0.1 _________________.______
.6 ------------------------
1.0
.3
.3
.3
.2
.2
.2
.1
.2 ________ 1________ ________ Beef,comed_____________________
.5
Lamb.._________________________
.2
Turkey---------.--------------1.0 ________ [________ ________ Beef (A. P.)--------.-----------1. 0 ________.________ ________ Beef (E. P.)___._________________
1.2
1.0
1.0
.9
.9
.7
1.0 _______ . ________ ________ Liver-----------------.--------1: :::::::: :::::::: :::::::: Veal____________________________
.6
-5
.9
.8
1.0
1.0
1.3
1.7
.9
1.3
1.0
Pmtemln~-
Group 9
1.5
~~~~.;i::::::::::::::::::::
1.5
Flo:, ~hole-WbMC:::::::::::l
Com
Flour,meal______________________
rye_______________________
Hominy________________________
Bread, j:rahBm_______._______
-------- .------- -------- Bread, whole-wheat..__________
---------------- -------- Bread, rye_____________________
1.0
1.0
1.0
LO
.7
•7
~=-
-
II~:~~~ --~~~.!~- -~~~- -~~~:~- -~~- :::::=== ::=:::
1_ 7 ________ ________ ________ L.______________
1_0 -------- -------- -------- 2_____
200
,,'5.075
16
0019
Hit! ~ = :~ ~I~ ~ ~ ~ ~~~:~, fi:~=:~~~::~1jj~m~~ n :I ~~==~==:~~~~~~~ ~~::~~~~
~..:i=:::=::=:-:-= Ui:! ~~~~~~~~~~:~~~~~ ~~~:==~::::~::: ::~;:::~~::::::~: ::~~:m~~:== ~::m -------1
:~1
:~
:'_::::::1:::::::: ::::::::
1.5 --------1-------- -------1.5 -------. -------- --------
FBo~L~~~~::·_:::::::::::::_--__-_-_--_
.71
~
:~ :::=:::: ::::::=: ::::::::
.5
I
-------- -------- ---------------------------------------------------- -------- -------_______ .j'_------- _______.
.------- -------- -------­
-------- -------- --------
.7
::
.5
.5
.3
.7
.6
.4
--3;500- ------i'5' ---~ii7ii- ----~Ci7- --~ooiii- :::::::: ::::::
.
.
--1;000- --- - -7ii~ii- --~ii4i-----:75---~iiiiii:::::::: ::::::
-------- -------- -------- i 7.______ - ----- ·---300- ----·i~ii- --500- ------'2- ---ooio- -------- ------_--.-_:-_-_::_:_:_ :_-_._:-_.:__=_:.: _::_-_-_:-_-_::_:_1 8________-_· __- _____ ---·50--0-- -----90.---0-..- --.•~200---- ---1-.~02--- ---.-MM- -.--_-_:._._=-_._::. -_._:_:_::_-_-
:_:_:_:_:_:_:__: :_:_:_:_:_:_:_:_ -_-:_:_:_:_:_:_':_1 5________•_______
________________________ , 6________________
""""
9________________
10_______________
-----
--i;Giiii' -----iiO."ii- ---~3OO- ---i~7ii' --~iii7ii' :::::::: :::::: --i;6OO- -----5LO --:ioo- ----~42- --~OO4ii' :::::::: ::::::
Total__________________________________ -------- -------- -------Nutritive nIue of diet
GroupS
Group
t
Pecans, in shelL ___ . ____________ .!
Apricots, drled.------------------i
Potatoes, sweet.-----------------1
g~~:.::::==:::==:::::::=:=====lf·
~:rs~~:_f~~~.:::::::::::::::::::,
1
BlackberrIes_____________________
Currants, fresh___________________
Onions________________________ .__
Peaches________________________ __
.Apples___________________________
Boots____________________________
Eggplant (E. P.)_________________
~: ~
1.3
1.3
1.3
1.0
1.0
1.0
1.0
.5
iii~~~=:=:::==::=:=:=::::
:.5~
Muskmelon______________________
Squash___________________________
Cucumbers______________________
.5
.3
~~~on_=~:::::::::::::::=:::
:~
Peas, drled______________________
Beans, dried__________ ._________
Beans, kidney, dried__ •________ •
Lentils, dried___________________
Beans, lima, dried.. ____________•
Chestnuts________ .._____ •_____ ._
:~
.8 _______________________ _ ~~;groon~-iiip.;dS:::::::::::::
1.0 -------- -------- ________ 1
1.2 ____• ___________ --------, Com, fresh______________________
I:::::::: :::::::: ::::::::
1.2 ________________ --------:
.6 •_______________ -_______ .
.4 ________________ --------,
1.0 _______________________ •
1.0
Group 7
~
1.0
1.0
1.0
1.0
1.0
.9
:~
Cheese, .AmericaD______________ _
Cream, 40% milk fat •__________ _
Milk, condimsecL ______________ _
Cream, 18.5% milk fat_________ __
Milk,
fresh ____• __________
1.5 -------- -------- -------- Milk, whole,
skimmed, fresh
_____________
.6 ________ -------- -------- Buttermilk________
•___________
Whey_________________________ __
2.0
2.0
2. 0
2.0
:~ :::::::: :::::::: ::::::::
. -,......... ,.,,,"----,------,.1 -,.1 1------------------------
________ -------- ------------TotaL ____________________ -------- -------- -------- -------- -------.
i
Lard____________________________
Oils, table_______________________
Butter__________________________
Margarius______________________
Jelly___________________________ •
Sugar___________________________
.6
.6
:g:::::::: :::::::: ::::::::
---f-----+-----I------~'
Total. _____________________________________ -------- -------- --------1
6.0
6.0
5.0
3.0
1.0
.5
.5
.5
1.2
1. 2
1.0
1.0
.5
.5
0.0 ________ -------- -------0.0 1________ ------.- --------
f: g-_._-_ ..._._ . : :'.-.:'_=:: -_:::::::
1.0 ________ -------- ----.--0.0 ________ -------- --------
=::=:::=1===::::: ::::::::
TotaL __ m_m ____ m ___ . __ m __ I·____
Group 8
Group ij
1:.4
Group 10
MBC81'oni. _•___________________ _
7.0
Flour, whlte____________________
.8
Crackers________________________
3.0
Farina__________________________
.8
Rlce_________. __________________
1.0
1.0 --------'.------- -------- Coconut, fresh, in shelL_______ _
Bread, white___________________ _
1.0
Bread, Boston brown___________
.4
Peanuts, In shelL ______________ _
Flour, buckwheat_____________ _
Walnuts, English, in shell______ _
Fish
containIng
more than 5%
fat _______
•.. __________________
Cheese, cottage__________________
Almonds, in Shell______________ _
Fish containing less than 5% fat
4.0
3.0
1.7
1.0
1.0
.7
.4
.7
.6
1.2
-------- -------- --------\
1. 5
L__ _ _ _ _ _ _ _ _ _
II ____E_X_trB
_ _ _ _.I.P_OUD
__ds
__
C_al_orI_es
__
Pro_teln
__
1.0 ________ ________ ________
.4 ______________________ __
.4
2.0
2.0
.4 _______________________ _
Total_____________________________________ -------- -------- --------
1
I The figures used in this method are derived from the composition figures published by Atwater and Bryant (1) and Sherman (1f) for foods as purchased (A. P.) unless otherwise indicated 88 E. P., meanIng edihIiI portion.
Equlva-
Equi!R'
lent
lent
1.0 -------- -------- -------Cal­
Phos·
1.0 -------- -------- -------weight Energy weIght Pro­
Group
tein
cium phorus Iren
1.0 -------- -------- -------calorieI~
.9 -------________ -------________ -------________
pounds
pounds
.4
.9 __ ______________ --_----..11--------1-- - - - - - - - - - - - ---- ---­ ~
2.0
Calorl..
Gra17l3 Gram, Gram
1______ ...._____________________________
. Graf1l3
______________________•
____ __
--1==== - m l - -T-o-tB-L- - - - - - - - . .,- ;- - - .- - -. .;-I- - - -_- _- ~- - - - =- =- -4- - - - - - -=- :- - - - - - - -:- ~- - -_.- -
---------I---.J---II
ToteL ____ • _______________ -------. -------- -------- -------- -------­
1.0
1.0
1.0
1.0
1.0
1.0
cf_C_::n_-_I~
Gra1M Gra1M Grams
~::=:::===i=~::=~~~~~:~~~~~~l~~
l~~:
-'=::::::: ::=:::::: -:=--=:: ::::::::
:::::::: =:::::
_Ir_on_ 5_______________
Gram
... _____________ ; _____________ ...........__________________.....___ ............. 1."...-- ____ ....__
:~::::::
:~:=~::=::::J~~~~~~~~
~~~~~~~~~~===~~ ~~~~~~~ ~~~~~~~~ ~~~~~~~~ ~~~~~~
..1:::::::: :::::::= =::::::: :::::::: :::::::: :::::::: ::::::
8..____________
1-------- ----- ------- ------- -------- -------- -----­
~~~~~=:==I~~~~~~~~~~~~~=~~~~~~~~~~ ~~~~~~~~ m~~~~~ ~~~~~~
~t:::::: ::==~=.
~:~::~
da;.:I_______
----- ------- ::::::::::::::::
-------- -------- ::::~:::
-------- ------
- -- - ---·1---+----1----11
TOt.aL __
TotaL____________________________________________________________ . Per man per
21810"-211. (Face p. 8.)
SHOR~ METHOD OF CALCULATING NUTRIENTS IN THE DIET
,9
In the same way the dried beans and peas are used' as the basis
of the energy value for Group 4, but the protein and ~neral values
assigned to the group are about one-half those YJ.eldedby the
dried legumes. The dried fruits are used as the basis of the nutritive
value figures for Group 3; butter is used in Group 5; beef in Group
6; T/hole milk in Group 7; oatmeal in Group 9; and white flour in
Group 10. The nutritive values of Group 8 were determined largely
by the trial-and-error method.
•
After suitable nutritive values were assigned to the 10 groups, two
factors were calculated for each foodstuff (Table 3). The factors
headed Calorie are designed for use in finding the number of calorie­
pounds yielded by the various foods, and those headed Protein­
mineral for use in calculating the number of protein-mineral­
pounds. They were ascertained by dividing the actual cheinical
composition figures for the food by the nutritive values assigned
to the group in which that food occurs. The composition figUres
published by Atwater and Bryant (1), Rose (11), and Sherman (liB)
were used in this calculation. For' instance, with carrots the method
may be applied a.s follows: One pound of carrots yields 159 calories.
This figure is then divided by 300, the energy value assigned to Group
1 in which carrots occur, and gives 0.5, the calorie factor by which
the number of pounds of carrots consumed is to be multiplied. One
pound of carr'ots also yields 4.1 grams of protein, 0.197 gram of
calcium, 0.161 gram of p~hosphorus, and 0.0021 gram of 'iron. Since
the protein and mineral values of Group 1 are similar, being 4 for
protein, 0.20 for calcium, 0.16 for phosphorus, and 0.002 for ir'on,
the protein-mineral factolr for carrots is 1.
Not all of the protein-Jrrlineral factors given in Table 3, however,
gives values which agree with the composition figur'es as closely as
does that for carrots. Take spinach, for example. The composition
figures for spinach are 9.5 grams of prot~in per pound, 0.303 gram
of calcium, 0.308 gram of phosphorus, and 0.0163 gram of iron. The
values a.ssigned to GI'oup 8, in which spinach occurs, are 15 grams of
protein, 0.10 gram of calcium, 0.40 gram of phosphorus, and 0.009
gram of iron. By following the method jut'- described, the values
obtained are 0.7 for protElin, 3 for calcium, 0.8 for phosphorus, »ond
1.8 for iron. After expedmentation with a number of diets, however,
the factor 1.5 was choseu a.s giving the best results. If spinach
played an unusually important part in any dietary, however, the
results would be considElrably invalidated by these discrepancies.
Adjustments rsimilar to those made for spinach were made for many
of the foods.
HOW TO USE THE SHORT-CUT METHOD
A sample dietary is wOlrked out in Table 4 to show how the method
is used. The quantities ill pounds of the various foodstuffs consumed
are inserted under the heading Quantity consumed. These figures
are multiplied by the cruorie and protein-mineral factors j.n order to
find the equivalent weights in calorie-pounds and protein-mineral­
pounds.
The column of calori.e-pounds for each ~oup is totaled and
entered in the column hleaded Equivalent weIght calorie-pounds in
the section Nutritive value of diet. Each of these group totals is
21810'-29--2
10
TEOHNICAL BULLETIN 105, U. S. DEPT. OF AGRICULTUBE
then multiplied by the energy value for its respective group,as given
in the section Nutritj.ve value of groups per calorie-pounds and pro­
tein-mineraI-pounds. The results so obtained represent the number
of calories in. ea~h group ?f foods ~ the diet and. are entered in the
Ener~ column ill the sectIOn NutrItive value of dIet.
ThIs same procedur'e is followed for th~ remaining nutrients by
multiplying the group totals by the protein, calcium, phosphorus,
and iron group values. After all the entries are made in the section
on Nutritive value of diet, totals are struck, and the total calories
and grams of protein, calcium, phosphorus, and iron furnished by
the diet are obtained.
This will be more readily understood if a computation is carried
through. In the dietary shown in Table 4 there are two foods, rasp­
berries and carrots, which belong in Group 1. The figures, 0.8 pound
and 4.5 pounds are, respectively, inserted after raspberries and car­
rots in the column Quantity consumed. Since the calorie factor for
raspberries is 1 the value 0.8 is carried over to the calorie-pounds
column under Equivalent weight. The protein-mineral factor for
raspberries is 1.5; therefore, the value 1.2 (0.8 multiplied by 1.5) is
inserted in the protein-mineral pounds column under Equivalent
weight. For carrots the calorie factor is 0.5 and the protein-mineral
factor is 1. The value 4.5 is therefore multiplied by these factors,
and the results, 2.3 calorie pounds and 4.5 protein-mineral pounds,
are inserted in the proper columns under Equivalent weight. These
values are totaled and carried to the columns for calorie pounds and
protein-mineral pounds of Group 1 unde-r Nutritive value of diet,
at the lower right-hand side of the page. For this group they are
3.1 calorie-pounds and 5.7 protein-mineral pounds. The 3.1 calorie
pounds is multiplied by 300, the energy value of Group 1 shown
under Nutritive value of group, and the result (930) is inserted undel'
Energy for Group 1 in Nutritive vaJue of diet. The 5.7 protein­
mineral-pounds is multiplied by each of the four values shown above
for Group 1, 4 protein grams, 0.200 calcium gram, 0.16 phosphorus
gram, and 0.0020 iron gram, to get the values 23 grams of protein,
1.14 grams of calcium, 0.91 gram of phosphorus, and 0.011 gram of
iron, which appear after Group 1 under Nutritive value of diet.
The same J?rocedure is followed in calculating the nutritive value
of the foods ill the other groups. Foods not listed in the 10 groups
are placed in the extra space at the bottom and calculated by the
item-by-item method. The nutritive value of the whole diet is then
found by totaling the various columns in the lower right-hand corner
of the page.
FOODS NOT INCLUDED IN THE SHORT·CUT METHOD
Foods that have not been completely analyzed for all of the food
constituents are not provided for in the short-cut method. Nor are
foods like molasses, gelatin, maple sirup, brown sugar, and cornstarch
included because they art) either very dissimilar in composition to the
other foods or they are entirely lacking in some nutrient. If they
were always used in small amounts they could be fitted in with the
other foods without causinB' a large error. But since they play an
important p'ut in many dIets their inclusion in the method is not
feasible. It is best to calculate the nutritive value of these foods
(
I,
TABLE
FaCto~ ,
Quan,
1---,..---1 tity
Equivalent
we;ght
",
4.-SampZe dietary with nutritive value calculated by f.he new short-cut 1Mthod developed i'n the
Factors'
Quan·
1--'--;---1 ti~
~;d
Protein·
JProteIn.
Calorie min',
(1'.>& ) Calorie. min·
aral
"
poundzl era!·
Food groups
Equivalent
weight
Factors l
------·11
I~---.---I
Food groups
Protein·
Protein. s~.;d,
(lbs) Calorie. min."
Calorie min.
eral
. pounds oral·
pounds
~pounds
Quan·
tlty
Buteau
or Home 1ffcQM11r.~
Equivalent
weight
Factors I
1----.,---II
j--~--j
Food gron9tl
Protein·
Protein. s~.;d,
Calorie min. (lbs.) Calorie. mIil·
eral
pounds . oral·
pounds
Quan·
«~
Equivalent
weight
Nutritive value ot groupS, per calorlc·pounds and prote!D·minerJl1·pounds
r---.---~j.------~-_.---~--_.----~--
conProf.\lln
Protein· sumed Calorie. min •
Calorie min·
(100.) pounds eral:
DOunds
eral
Oroup
Cal·
clwn
Energy Protein
PhOlY
phorus
__-~~--
Iron
. ---.
-------·---·j---------------II-----------I------------II-----------·-----------ll-----------j·-----------ll-----+----------~-
Gr(}up 1
Figs, dded.___ •____________....._
Oi~ron,
dried..pickled.
_~ ...---..-.•·
____• __••._._
OlIves, green,
-.-1
~1':i~b~:~~:: :=:==::::=::::=:=
Parsnlps__ .--________________ •. __
Carrots_•• _•._. _., __. ___________ _
S trawbi'tries _________ • __ . _______ _
Turnlps_______________ • _________ _
Okm________________________•___ _
~=~~~~=~::==::=:=:::=:=::
Caullllowcr_______. ___. __ ., _._ •••
Kohl·rabi (E. P.} ..... __ .....___ •
·GmpeCruit._. __..______ .......__ _
Or,Ulges._________ • __•___ •••• ____ _
Lemons. ________________________ _
Rhubarb__• _____________________ _
Lettuce_____ •___________________ _
Celery__________________________ _
5.0
5·11
a.J
1.0
1.0
.8
.5
.. 5
.5
.5
.5
.5
.5
.5
.5
.5
.5
.2
5.0
1.0
2.0
1.5
1.0
1.0
1.0
1.0
1.0
1.0
1.0
6.0
3.0
1.7
1.7
O.s
O.s
1.2
.6
.6
.6
.6
1.0
.2
.2
1.0
TotaL ___________________ . ________________________ _
~
Pumpkn_ ~_.
2.0
1.7
I.7
1.7
1.3
1.3
1.3
1,3
1,0
3.1
5.7
1.0
1.0
1,0
.5
.5
•5
,5
.5
.5
.3
.3
.3
4.0 _____________ . _________.
4. 0 _. ____ .. ________ ________
1.0 . _____________•..____• __
1.0 _______• ________________
.6 ____ . ___ ...__. _________. ,
:~
LO
2. 0 _______________________• Pork, salt_______________________
2. 0 _______• _______________ _ Bacon___________________________
LO
LO
LO
LO
.2
:~
.1
U -----~5- -----~i----"'~81.0 ________ . ______________ _
l:g•3
.3
:
~
~.
Cabbage. __ • _____________ . ___••_
Asparagus _____. __________ • _____
Plrieapple (E. P.} ______• __ • _____
Cranbenies••___________________
.1
.1
.6
iI.5
.7
3.9_
.4. _______________________
.1
.2
.1
::::.--- ::::---- ::------'
.6 ________________________
r------- -------- -.------
TotaL _________ . __________. __._____ ________ ________
9.0
:: ---"7:4- ---"7:4' ---Tii-
8.5
2.6
2.0
1.6
1.6
1.2
1.2
1.2
1.0
1.0
.11
.9
:~ :
.5 .
.5
i ::::~=~: ::::~=~:I===:~=~:I
Cocoa••••••••••••••_________._._
1.5
Chocolate_______________••_____ .
1.5
Bran, wheaL ______________ •___ •
Cowpeas, drIed ________________ _
1.0
J
OatmeaL_______________________
1.0
Flour, gT!lham__•______________.
1.0
.8 ________________________ Wheat, shredded____________ •.
1.0
•D _______ • ________________
1.0
.8 ________________________ Flour, whole.wheat___________..
__________ •__________
1.0
LO ________________________
1.0
1.0
LO
as
al
~s _
1.3 _______________________
.7
Bread, whole-wheat_____....____ •
1.1
.2
.1
.3 Bread,
.1
rye ______________________
.7
La~ ________________________
0:
J:::::::: ::::::::1::::::::
Commeal~
i:~~~~::::::::::::::::::
. -------- -------- -------­
LO ________________________
Total ____ -_______________. ____• ______________
Group 1
1. 0
1.0
1.0
1.0
1.0
2.0 . __________________• ___ _
2.0
1.2
1.2
2. 4
2.0 _. ________• ________. ___ _
2.0 _________•_____________ _
1.5 ________ .•_____________ _
Cheese, American_____________._
Cream, 4Q per cent milk tat.___ _
Milk, condensed__ . __________ • __
Cream, 18.5 per cent milk tat___ _
Milk, whole, fresh_••___ . ____ ._._
6.0
6.0
5.0
3.0
::
:g -----::7- -----::3- ....-~6"
W~~~~:~~:::::::::::
Whey___________________________
.5
.5
. -------3.0 -------.6 -------.9
--5-3'.-3-- --2--.0-- p~. green m' pods
2
3
.S
2.
~,
, green, In
------------1.0 ___• _______________. __ .• Beans,
lima,
pods ___.__
.2
.3
~: ~ -'--7~3- -'--7:3- ---Tii- Com, fresh..____________________ - . : : . _ _
1.0
~7
~7
~7_
1.0 ___________________.
___
1.0 ._.•____ •______________ _
17.4
-s
~=~~~~=::=::::=:::::::::=::::
~:~,<:ri~~:=:::::::::::::::::::
FowL_.___. ____________________ _
Liver__________ •_____• _________ _
1.5 _______________________ _ VeaL _____________• _________ •__ _
.1
Peas. drled ____________ • ______•
Beans, drled __ ..________________
Beans, kidney, drled.____ .______
Lentils, drled___________________
Beans, lima, dried______________
Sausage_______________________ _
Ham, smoked_______"___________
1.0
.4
.4
.4_ Ooose__________________________ _
L
0 _______________________
.6 _______ . __________ . ____ _ Mutton_________• _____________ __
.6 _______________________ _ Porlr______________<___________ _
Beet, corned___________________
Lamb_________ • ___ . ___________
~
---22."5"
----6~ii"-ii~3"
•2 _______________________ _ Turkey__________ ______. ____ _
1.0 _______________________ _ BeeC (A. P.}________ . ______ •_____
1.0 ___________________ ..__ .
1.0
1.0
1.0
1. 0
Splnach___ ..._________ ... _______ •
Group
9.0
6.5
3.0
1.0
_ _ _ _ _ _ f_ _ _ _ _ _ - _ _
Group!
Pecans, in shelL_______________.._
.Apricots, drled ________________••
Potatoes, sweet___•._____________ _
Plums__________________________.
Grapes___ . _____ . ___. ___ . _____.. __
Cherries_______ •________ •._. ____ _
Apricots, Cresh. ________..__._. ___
Pears_______ •__________ ..___• ____ _
Blackberrles___________ •_______ ._
Currants, fresh __• _____ • _____ •__._
OuIons______ • _. _.___________...__
Peaches________________________••
.\pples______________ •_____ . ______
Beets ___ •______________________ _
Eggplant (E. P.}_____....._______
Peppers, green__________________ _
Tomatoes______________• ________ •
Radishes______________ . _________ _
Muskmelon_________ •___________ _
.8quasb..________ __ • ____________ _
cucumbers______________• ______ _
___________________ _
Watermelon_____________________
Coconut, driad__. __ • ___________ _
Currants, dried. _______________ _
Prunes, drled _______ • ___.•______
Raisins_ •• _________• ___________ _
Dates, drled__________________ __
Tapiooo__________ • _____________ •
Apples,
Honey_.dried_.--------------___________ . _________. __
__
l'otatoes____ ••._______ _______._
Bananas_______• __ • ____.•_____ _
Dandelion greens__ . __________ __
Mushrooms ____________________ •
Clams (E. P.}______________ __
OY,StersstrlDg________
(E.. P.) - ---.-------.-.-Beans,
• ____._.__••
~
________________ t .. _____ _
GrDup9
Groop8
GroupS
.
.1_::::=::: ===
Total ______________________ -------- -------- --------
2.1
===
3.9
LO
.5
7.0
.8
3.0
.8
1.0
1.0
1.0
.4
i
9.1;
0.2
----1----37.3
0.2
.9
.9
.6 .5
.5
.3
:~ I----=~:- ----.~~- ----=~~.
Lard________________________. __ _
Oils, table_________________. ____ _
.6 __________________. ____ _ Butter________________• ___••___ _
.4 •__• _______________• __ __
1.2
.6 _•. ____________ ••__• ____
1.0
1.0
.s ___.__________.. ________ i':u~~:-~:~::::=::::::::::::
.2 ________________________ Sugar___________...______________
1.2
.0
.5
0.0
0.0
1.0
1.0
1.0
0.0
.2 • _____ ._ Peanuts, In shell_______________ _
4.1 _______ _ Flour, buckwheat..____________ _
3.4
Walnuts, English, In shell__._.__
'--"3:5' '--"3:5- ---T,5" Fish,
more than 5 per
centcontaining
taL ______________________
1.0
.5
1.0
3. 6
1. S _______ _ Cheese, cottage_________________
Almonds, In shell______________ _
Fish,
less than 5 per
centcontaining
tat. ______________________
.2
~
1.0
1.0
.7
4______• _______
--i;OOO- -----iiii."ii- -'-::300- ----~8ii- --~iii4ii- :::::::: ::::::::
I
26. 3
22. 5
TotaL______________•__.__ _______ ________ ________
10..1
4.5
TotaL _________________ •__
----roo-
-----jjjj~ii-
---:200- --Too-
==:=:::: :::=:::=
--~iiii.50-
--i;600- -----iiii~ii- ---~3OO- --Tiii- --~iii7ii- :::::::: ::::::::
1(1.__...________ --i;OOO- -----iii:ii- ---:ioo- ----:42- --:&i45- :::::::: ::::::::
4.D
4.0
Nutritive value oC diet
LO
L2
LtJ
1.0
1.0
1.0
LO
_1
.9
.4
.9
1.0
LO
L(I
_6
=
Ey:r­
Equlvalent
'gh
E
welght Pro::l~
nergy proteln- teIn
Group
----1:~- --~G:3- ----6:'8"
pounds
Calc\um
Phos- Iron
phorus
:;to ---------- - - - - - - 1 1 · ' - - - - - - \ · - - - - - - - - 1 - - - - - - ­
'l'tmd
~
PmteIn•
o.
.
C!1am
~. .
Iron
~-------- ---0:0- -~iiOO- --ii:i- ---iil--Tii- -O:9ii"
--:i57
4..._ _ _ _ _ ---:if-3,3ei)- ---"i'D- ----2:ji-
--~iiM
--ri7 332-
tJ ::::::::::::::::::=:::::
e:~ ~ ~------ _~!_ ~~=~4.. _==~~-- :~~=~:~~=:~
---.---- -------- -------- -------..----.-----.--' -------. ~:~-.---6'.._______
~! ::=:::::::::::::::::::::
~~~f~~f~f~I~~~~~~~~~~~~~ =~~~~=====- :g,__ -~,--~~
}Ir~= ~~:~_~~~~~~=~~~r
------------------------ -----------------------------.--------- ---u
aBO .068
Molasses______________•
0..2>
26().
:
====:==1::== ==
The fi~es lJlled In this method arc derived from the composition figures published by Atwater and Bryant (1) and Sherman (It) Cor Coods as pureni1S6d (A. P.) unless otherwise Indlented as E. P., meaning edible portion.
9_1
~
0.'lOO
1.%
liO!
_30
T~.
4..&'
2«t
I.2ft
~4Q
.079
:i5_\Ii - 25;.W> --liT --837 -1:14- "7.31 --:078
.. ];xtra..._____• ______ :......--------­
200' ----___ ----Z ----.1D
.04.007
; 10,-_
Total___________• _______ • __ . ___________________.___
..-~iii5- ----~iii- --~ooiii- :::::::: ::=:::::
--i;ooo- -----i6.-i)- -'-~ioo- ---'~4ii- --~OO9cj" :::?:::: :=:=::::
Cdorlu
Or4_ Ortl.fIfJI OrCIlM Gram .
3.1
930
6.7
ZI
L14
0.111 0.011
I---I---t----l---~--_\Il------------TotaL_._ _ _ _ _ _ _-I~____ - - - - - - . l5..9
.17.~
2._________ --26:'3" --5;260- ---22:6- ---i2i- --['00- ---3:'00- -~043
Extra
4.0
3.0
1.7
------~5-
Gram
il.OO2O _____________•__
3______________
8..____________
11---------;;----1----------"­
Group 8
Gr!>Up 6
2______________ ----200-
Gram Graf/18
0.200
0.16
7________ .----- ----300- -----i5~ii- ---::500- ----::~ --::ooiii- :::::::: :::::::
.7
.6
.4
Total____________________________________________ _ 1.2
C~
37.2
1.0
2.0
1.6
1.0
Graf1l8
4.0
9_____________
G""'1I 10
.1
.6
_7 :rvIIICIIr1IIIL _____________________
________ ________ _____ PJIIUr. wbiht__________________
2. 0
10.0
11'.1); ()'mdw'Sc_______________________
_________------ _____=-::- . .F8ri:nII____________________
22. 6
22. 6
22.5, Rb________________________
________ ________ _______ .
fresh.lD
_______
8. 0
4. 0
S.O'· BreacJ,. wiIfte____________
________ ________ ________ Brad;. Bo8t8Ia brow"A______
Total _____________________ .____ ________ ________
0.1
1.7
,... _--_ ... - .... _.. _--- Caloria
300
.
--
~
---.. --.. - .. ---- --- .. --- ------ - ...
Total_____________ ____
211Q'!
2:0.
..19'
• 04!
•.091.: ~~~~== ~.~
_
----_.
.... - .. _-----
------
__ __ __
==~~:I-=·~~- ~: ~~~
218IO":"'29'.
(Jr1lCe'P~ lll~)
:~
SHORT METHOD OF CALCULATING NUTRmNTS IN THE DIET
11
separately and to add it to the total diet. Provision is made for extra
foods in the form suggested in Table 3.
Canned foods are another' class not included in the short-cut
method. Few analyses of canned fruits a:q.d vegetables have been
made, and the only li!omposition figures that can be suggested are but
rough approximations. Their inclusion in the short method of cal­
culating the nutritive value of the diet was therefore not attempted.
For studies of food consumption containing canned foods, however,
some provision must be made for calculating the nutritive value
yielded by such foods, and the method used in the Bureau of Home
Economics is probably as good liS any that can be suggested at the
present t.ime. From standards which have been worked out by can-I
ners' associations and by the Food, Drug, and Insecticide Aclininis­
tration of the United States Department of Agriculture, the evidence
is that the edible material used in commercial canning is, on the whole,
60 per cent of the net weight of the canned food. This holds fairly
well for all of the fruits and the vegetables except tomatoes which
are 100 per cent edible material. In order to fit a fi~ure for edible
material into the short-cut method presented here it IS necessary to
include the refuse, since the method is based on foods as purchased.
An illustration to show how to calculate the nutritive value of
commercially canned foods follows. If a food-consumption record
shows the use of 100 pounds of canned string beans, the assumption
that 60 pounds of fresh string beans (E. P.) were used in canning
that amount is probably not far off. In order to fit this figure into
the short-cut method, i.:; is necessary to reduce it to an " as purchased"
figure by the use of data on refuse. Atwater and Bryant estimate 7
per cent of refuse in string beans (1, p. 65). It would therefore re­
quire about 65 pounds of string beans, as purchased, to make 100
pounds of canned.
Figures for canned fruit are somewhat less simple because of the
sugar that is added. The commercial grade most commonly used is
choice, which contains sirup with 20 to 25 per cent sugar. On drain­
ing, commercially canned fruits yield about 60 per cent solids and 40
per cent sirup. In estimating the nutritive value of canned fruit,
the procedure for arriving at the amount of raw fruit used is the
same as that for the raw vegetables, and the sugar that goes into
canned fruit may be estimated from the: sirup. For instance, if 100
pounds of commercially canned peaches are reported as consumed,
it probably consists of approximately 60 pounds of solids and 40
pounds of sirup. If a 20 to 25 per cent sirup is assumed 8 to 10
pounds 'of sugar were used in the 100 pounds of canned peaches. Ac­
cording to Atwater and Bryant (1, p. 713), peaches have 18 per cent
of refuse. Approximately 73 pounds of peaches (A. P.) are there­
fore required in cannin~ 100 pounds.
Such a method of arrIving at composition figures is unsatisfactory,
and for many foods it may ~ve incorrect results, but until more
accurate figures are available It probably gives as good an estimate
as can be made.
EVALUATION OF THE SHORT· CUT METHOD
The short-cut method presented here has been carefully checked
for accuracy. During the process of perfecting it, 25 representative
12
TECHNIOAL BULLETIN 105, U. S. DEPT. OF AGRIOULTURE
l'ecords of food consumption. were used . .A. short method that would on the whole, give. results for the 5 constitu~i1R; within 5 per cent of tho~ obtained by the it.em-by-item method was the goal. When the differences obtained on the 25 records indicated that the goal had been reached, 96 additional records were studied. Altogether there­
fore 121 records of food consumption, maue up of three different types, were used in checking the accuracy of the method. Forty­ f'/even collected by the survey method WE,re r.ecords of the food con­
sumed by farm families during one year; 50 were weekly dietaries of family groups; and 24 were weekly dietaries of institutions. The weekly records were collected by the aC<'.ount method. \. In practically all cases the results ohtained by the two methods of
calculating the nutritive value of the di1,~t were remarkably close. In
every case the short-cut method gave figures for energy within 5 per
cent of the long method and in 85 per cent of the cases for the 4
nutrients. Only 3 records, or about 2 per cent, caused differences
greater than 10 per cent. in the 4 nutrients-protein, calcium; phos­
phorus, and iron.
To express the results in more precise terms, the standard error of
$timate for the energy figures obtained by the use of the short-cut
method in 121 dietary studies is 2.3; for protein it is 3.6; for calcium,
2.8; for phosphorus~ 3.5; and for iron, 3.2. This means that in two­
thirds of the cases studied the results for energy derived by the short­
cut method did not deviate more than 2.3 r-!Jr cent from those given
by the long method; for protein they wer~ within 3.6 per cent; and
for the minerals they were within from 2.8 to 3.5 per cent of those
obtained by the long method. These figures, together with the standard error of the means and the mean value of the ~~hort-cut. method
expressed in percentage of values obtained. by the long method, are
shown in Table 5.
~
~
TABLl!l 5.-Standara errors of estimate for the ellergy, protein, calcium, pMS­
pllOrUS, ana iron values obtainea by tM s1wrt-out metlwil O'I~ 121. dietary studies ana the mean t'alues given by the Bhort-cut method expressed in terms Of percenlage of 1M values obta-inedi by tM long metlwa St~ndlU'd
Energy and nutrient
error of
estlmnte 1
Energy___________________________________ _ Per cent
Proteln__________________•_________ ••____ _
Calclum____________________ . _____________ _
Phosphorus______________________ . ________ _
lron________________________________ •______
1
2.3
3.6
2.8
3.5
3.2
Mean value
o( short-cut
3 X stand- method In Standard 3 X stand­
ard error o(~~:~f error of ard error of
mean'
mean
estimate talned by
long
method'
Per cent
Per cent
7.0
10.8
8.4
10.5
9.5
The standard error o( estimate was calculated by the (ormula ,;};:"
99.2
99.4
100.2
98. i
100.6
Per cent
0.20
.32
.25
.27
.28
Per cent
0.60
.96
.75
.81
.84
It Is the square root o( the sum
o( tho square of the deviations from tho long method divided by the number o( items .
• Tbls was obtained by adding the deviations (rom the l<lng method and dividing by the total number of
Items. T"~ deviation thus given was added to 100.
__
• The standard error of the mean was csIculated from the standard error of estlmata, thus ls'-c'
c being the deviation or the mean value of the various nutrients cs1cu1ated by the short-eut method from
Ule loni method, or 100 per oont.
1I-n-'
I
I
r," v.
~
,)
SHORT MET;HOD OF OALOULATING lTU~~NT8 IN THE DIET
I
!.
13
Table 5 shows that in no case do the meaIivalues obtained for
energy and the four nutrients by the short-cut method coincide with
th<>re'given by the long method. For energy it is 0.8 per cent below
the long method, which was used as the standard, for protein 0.6 per
cent below, and for phusphorus 1.9 per cent below. For calcium it is
0.2 per cent above, and for iron 0.6 per cent above the value given by
the long method.
The question naturally arises whether these discrepancies are sig­
nificant~ That is, does the shurt-cut method tend to give values for
energy, protein, and phosphorus below those derived from, the long
method~and for calcium ana. iron, values above the long-method fig­
ures ~ To test the reliability of the mean values for these essentials,
their standard errors were calculated. In Table 5 formulas are given
to show how these values were derive(t. On referriny to the last
column of Table 5 it is seen that the means of an additional sample
of the same size chosen in the same way as the first would in all
probability not ya1'y from the means of the first sample by more than
~
~/~+-+--f--I-I--f--t-+-
~/o~~-r~;-+-+-r-r ~ ~ "I--I-+-l-t-+-+--'-+ ~
FIG. l.-DlRtrlbutlon of the percentage of deviations from the item·by-stem method
.:
obtained by calculating the energy of the diet by the short-eut method,
0.60 t.() 0.96 per cent, or three times their standard errors. The energy
values would range, accordingly, from 98.6 to 99.8; protein, from
98.4 t.() 100.4; calcium, from 99.4 to 101; phosphorus, from 97.3 to
98.9; and iron, from 99.8 to 101.4 per cent of the values obtained by
the long method. The protein and calcium values calculated by the
short-cut method would, therefore" ill the long run probably approxi­
mate those given by the item-by-item method, but this method would
give values for energy and phosphorus on the whole somewhat below
those obtained by the long method, and for iron slightly above. In
other words, the short-cut method tends to give figures for protein
and calcium which agree with the long method, but there is a slight
bias in the energy, phosphorus, and iron figures.
The same thing is shown in Figures 1 to 5. The histograms for
protein and calcium show that approximately one-half of the food
records fall on either side of the standard (100) as well as of their
respective means (99.4 and 100.2). For the other three constituents
the case is quite different. For energy 54 per cent of the records Ere
below the mean (99.2), whereas 63 per cent are below the standard
14
TECHNICAL BULLETIN 105, U. S. DEPT.
or:
AGRICULTURE
(100); for phosphorus 59 per cent are below the mean (98.1), and
75 per cent below the standard (100); and for iron one-half of the
records are below the mean (100.6), but 43 per cent are below the
standard (100).
FIG. 2.-Dlstrlbutlon of the percentage of deviatIons from the ltem-by-item method obtaIned by calculating the protein of the diet by the short-cut method A summary of these findings may be helpful. Of the 121 dietari~s
studied by the short-cut method, 103, or 85 per cent, gave results for
the 5 constituents within 5 per cent of the long method; the standard
errors of estimate ranged from 2.3 per cent for energy to 3.6 per
cent for protein. The protein and calcium values calculated by this
method tend to agree more closely with those derived by the itemby-item method than do the energy and phosphorus, which on the
~
.~/O
~
~
SI--t--t--t--1I--1--+--II--I--l-
FIG. 3,-DIstrlbutlon of tbe percentage of deviations from the item-by-Item method
obtained by calculatIng the calcium of the diet by the short-cut method
average fall below those obtained by the long method, and the iron
value, which falls slightly above.
In order to estimate how large an error may be expected from the
use of the short-cut method in analyzing other food records chosen
in a similar manner, figures for three times the standard error of
J
,
SHORT METHOD OF OALOULATING NUTRIENTS IN THE DIET
15
estimate are given in Table 5. 'fhese indicate that the chance is very
good that the short-cut method, when used to analyze any single
food record chosen as were the 121 used in this study, will give an
energy value within 7 per cent of the long method. For protein the
value will be within 10.8 per cent; and for the minerals, within 8.4
FIG. 4.--Dlstrlbutlon of the percentage of deviations from the Item-by-item method
obtained by calculating the phosphorus of the diet by the short-l:ut method
~
~
to 10.5 per cent of the long method. The method probably gives the
most reliable results for energy and least reliable for protein and
phosphorus.
A study of the effect of the different foodstuffs occurring in the
121 records on the accuracy of the short-cut method shows that only
jO~r-~~~~-r-r-r~~~~-n~r-r-r-r-~~~~~-r-.
~
"~2$1~~~~.~~~~~~44~~~~~~~~~~
~ 20~+-+-+-~~~~-+-+-+-4~~~~~~+-+-+-~~~~~
~
~~~~+-~~4-~~4-~ ~
~/O
~~
~~~+-+-~~-+~
FIG. 5.-Dlstrlbutlon of the percentage of deviations from the ltem-by-Item method
obtained by calculating the Iron of the diet by the short-cut method
a few foods when eaten in large quantities are usually responsible
for the wider discrepancies in the results obtained by the two meth­
ods. The results for energy were so close in all cases that no study
was made of the effect of the various foodstuffs on these figures.
Table 6 gives a list of the foods occurring in such large quantities in
16
TEOHNIOAL BULLETIN 105, U. S. DEPT. OF AGIUOULTURE
the 121 dietaries used in this study as to cause. discrepancies 'in the
protein and mineral figures when calculated by the short-cut method.
T.ABLE 6.-Food-B occurring in the le1 dlet~rif:8 8tudlelZ that cau8ed) discrepancie8
it. the re8ult8 obtGinelZ 1Jy the 81wrt·out metholZ due to a1~ unusua"llll large
quantity
OOl111Ume~
Nutrient alIected
Proteln.-•••••••••••••••••• -••
Food
Results compared with
those obtelned by
the long method
l~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Bell~:
Flour. whole-wheaL_ ••••••••• __._..............
Do. FlOUIS. barley and ~e••-.-•• ---................. Above. Do. Com, fresh••••••••••••••••• _....................
Com ineal_••••••_•••••••••••_..................
Do. C.'clum
W
- - . _ . - . - - - - - - • • - -• •- - Cream 40 per '-'8nt milk CaL__•••__••••_........
Do. . Dandelion greens.•••••••••.•_••••••_........... Below. Raspberries•••••••••••••••••.••••••••••••••••••• Above.
11~lours. barley and rye ••••.••••••••••••••••••••• Below.
~~eans. drled._ ••••••••••••••••••••••••••••• _....
Do.
PhosPhorus._ •••• ____________ ,,~~com. fresh..____•••••••••••••••••••.•••••••••••••
Do.
Flsh._ ••••• ___•••••••••••_•••••••••••_..........
Do.
I
~= ~n:_~~==::::::=::::::::::::::::::: Abo~:'
.......-........-......... {
Iron-
Flsh._••••..•••••••••••••••_•••_ •••••.•• _••••_.. Below•
~~s~~::.:::::::::=:::==::::::::::::::::: Abo~:" A. glance at Table 6 shows that fish and the cereals-especially th~
whole-grain kinds-cause discrepancies for most of the fournutrIents.
Crea:m tends to invalidate the results for calcium and the ~gumes
!or pho~ph~rus. Of co~e, if an~ ~I?-e foodstuffs plays;a lar~ part
In the dIet, lt may cause InaCCUraCIes III the ~ults. ~aspberr1es, for
instance, consumed in quantities as large as 1% cups per man per
daYr or .about two- good-sized servings.-every.. day:, .may throw t~e
calcium figures out· c.onsiderably. Such seaso~al indulgence,. how­
ever, does not ordinarily influepce the t;esults t~ this. extent wheJ;l. the
l'ecords of food consumption are kept for a longer period than a
week or two.
When there is a combination in the diet of several foods which
cause the same type of error in the values obtained by this method,
the possibility of a large discrepancy in the final results is increased.
For example, the short-cut method gives protein results for fish,
hominy, and corn meal below those obtained by the long method.
If these foods playa prominent part in the diet, the protein as indi­
cated by the short-cut method will in all probability be much too
low. In the same way, if corn, corn meal, and heavy cream are used
in abundance the amount of calcium indicated by the short-cut
method will be to\) hi ah.
In choosing a method for analyzing a particular collection of
dietaries the investigator would naturally ask how much time would
be saved by using this short-cut method instead of the item-by-item
method. Five statistical clerks in the Bureau of Home Economics
tested this point by calculating 36 dietaries. The results given in
Table 7 shows an average saving of 42 per cent of time by the
short-cut method. Although these figures do not reflect the influence
of the number of foodstuffs in the dietary on the amount of time
saved because of the individual differences which enter in, such a
SHORT METHOD OF CALCULATING NUTRIENTS IN THE DIET
17
relationship is indicated by the individual reports. Other things
remaining equal, the proportion of time saved in making a calculation
tends,to mcreaseas the number of foods increase. The s~!De tendency
was pointed out by Hunt (5, p. 212).
.
TABLl!l 1.-Compari8on of the time required for calculating dietarie8 ~U the
81wrt-out metlwd with tll~f by the long method, as shown b1l the calculatiun
of 96 dietarie8 by 5 workers
Ayerage time
Initials of worker
Diets·
spendie.:~
-.
Average time
Average
number
rfes ana'/_ _,--_ _/5aved by sbort- of loods
lyzed
cut method per dietLong Bhort
ery
method method
---------------------~---r___----!----I----~---~----
M. M ......._ ........_ ......._...................
Number Hours Hours Hours Per «nt Number
A. B ......................................_........
K. B................................_..............
II
3
9
6
Average.......................................
H. N_..............................................
H.
C................................................
1.6
9
3.1
2. 9
3.3
2.1
1.7
2.0
1.3
1.2
1.5
1.4
1.3
.8
.5
48
56 48
50 39
49 3865 211
58 7.2
2.6
1.5
1.1
42
1.5
56 The reasons for analyzing a dietary and the degree of accuracy
desired and attainable should be kept in mind in deciding on the
riJ.ethod to use in an analysis. .A. dietitian, for instance, who has a.
very sick person's welfare in mind should doubtless calculate the nu­
tritIve value of the diet as accurately as possible by the item-by-item
method. A statistician, on the other hand, seeking to show from a.
large number of records the deviations from the average diet or to
correlate diet with other factors aifecting the welfare of the indi-.
vidual would be justified in using a shorter method of making the
necessary calculations. If the data under consideration are estimates
of food consumption rather than careful records, a method even
shorter than the one presented here might be desirable. An analyst,
on the contrary, making a metabolism study of these nutrients woul<'.i
not only use the long method for analyzing the diet, but his calcu.:.
lations would be based on figures from chemical analyses of the par­
ticular foods used in that diet rather than on average food-composi­
tion data.
In stUdying the accuracy of the short-cut method presented here,
the results were compared with those obtained by the item-by-item
method, but it should be remembered that the latter ma.y contain
many inaccuracies. In both cases the composition figures used in the
analyses are average values taken largely nom the tables com1?iled
by Atwater and Bryant (1), M. S. Rose (11), and Sherman V93).
The former show the number of analyses used, the percentage of
refuse~ as well as the ,average, maximum, and minimum percentage
of water, protein, fat, carbohydrate, and ash, and the fuel value per
pound. Rose has calculated from Atwater and Bryant's tables the
actual energy and protein values for the various foods, and these
were used in constructing the short-cut method. Sherman's tables
show only the average composition figures for minerals without
any indication of the variations existing in the data on which they
were based or the number of samples that were included in the mean.
18
TECHNICAL BULLETIN 105, U. S. DEPT•. OF AGRICULTURE
It has been possible however, to get somewhat more information
about the reliability of such figures than is given in the composition
tables. Tocher (13), for example, analyzed 709 samples of milk from
individual cows in different parts of Scotland and found a protein
average of 3.2 per cent, with a standard deviation of 0.4. Thismeans
that the coefficient of variation for protein in milk is as high as 12.5
per cent (0.4 multiplied by 100 divided by 3.2). These samples also
showed high COEffiCIents of variation for the other factors. For ash
it was 7.2 pel' c~nt, for fat 19.8 per cent, and for lactose 8 per cent.
A great number of food analyses have been brought together in
the Bureau of Home Economics. Some of these were studied by the
writer for coefficients of variation for protein and total ash. On the
basis of 81..7 analyses, potatoes had a coefficient of variation of 22
per cent ·for protein and 17.5 per cent for ash. Eggs, on the basis
of 97 analyses, showed a coefficient of variation of 8.9 per cent for
protein and of 25.8 per cent for ash. Flour is a very indefinite term,
because of the many factors which affect its composition. Wheat
flour, described by Atwater and Bryant (1, p. 58) as patent-roller
process, family and straight grade, represents a grade in common use
in the American household. Figures for straight flour from winter
and spring wheat are given separately here, but unless the investi­
gator is able to determme the origin of the flour in a given dietary
he would probably use the average of all analyses. The accuracy
that might be expected from such figures was investigated by the
writer. Seventy-six samples of straight flour analyzed largely in the
California and North Dakota experiment stations showed a coeffi­
cient of variation of 35.4 per cent for protein and 51.3 per cent for
ash.
'With such variations as these occurring in the foodstuffs that
play a prominent part in the diet of the American people, one can
hardly expect a dietary calculation based on average composition fig­
ures to be 100 per cent accurate. The probability is ffiight, however,
that such variations in food composltiQn are entirely cumulative
in their effect on the nutritive value of the total diet. To test this
point, a few comparisons were made by the writer. Dietary analyses
made by the use of actual food-composition figures were compared
with those in which average composition figures were used. The item­
by-item method of analysis was used in both cases. The results indi­
cate considerable variation. Five studies showed a discrepancy of 2
to 8 per cent for energy and 2 to 25 per cent for calcium. In six
studies the error in total protein due to the use of average composition
figures was from 0.5 to 25 per cent, and in three studies the phos­
phorus error was from 8 to 14 per cent.
These diets were used in metabolism studies and were therefore
limited in the number of foodstuffs included. More varied diets
would probably show closer agreement betwe~n the results obtained
from average composition figures and those based on actual analyses.
The possibility of errors r'esulting from the use of average compo­
sition figures alone should be kept in mind, however, and since such
data were used as the base for measuring the accuracy of the short­
cut method presented here, the true error in the various constituents
calculated by this method may be somewhat greater than indicated
4
1
SHORT l'<lETHOD OF OALCULATING NUTRIENTS IN THE DIET
19
in Table 5. If better average composition figures become available
at any time, the short-cut method will need revision. The principle
on which it is based, however, should hold.
SUl\IMARY AND CONCLUSIONS
Although data on food consumption of over 15,000 families in the
United States have been collected during the past 50 years by
various investigators, this material has not been analyzed sUfficiently
to give the informaLion now demanded on the nutritive value of
these diets. The time and labor invol¥ed in dietary calculations
by the long method has been one of the greatest drawb,~cks. To
overcome this difiiculty, short-cut methods were suggested by Caro­
line L. Hunt and Anton R. Rose. Neither of these, however, pro­
yides for calculation of calcium, phosphorus, and iron. Since these
minerals are now lmown to be of great importance in nutrition, and
since many American diets are believed to be deficient in one or
more of them, a new short-cut method of dietary calculations was
developed in this bureau so as to obtain figures on these three minerals
as well as on (,!lergy and protein.
From a study made with 121 food records to check the accuracy
of the method, it was found that on the whole it gave results within
5 per cent of those obtained by the lon~ method. Furthermore, the
results forecast that an investlgator usmg this method for calculat­
ing the nutritive value of a varied diet should expect agreement with
the long method within '{ per cent for energy and 10 per cent for
protein, calcium, phosphorus, and iron. Investigation of the time
element shows that this method saves on the average about 42 per
cent of the time necessary for the long calculation. If at any time
the average food-composition figures used in making dietary calcu­
lations are revised, the short-cut methods based on those figures' will
also need revision.
LITERATURE CITED
(1) ATWATER,
t
w.o.,
and BRY_-\NT, A. P.
THE CHEMIOAL COMPOSITIO::s" OF AMFlIIOA...-; FOOD MATERIALS. U. S.
Dept. Agr., 011:. Expt. Stas. Bul. 28, 87 p., illus.
(Revised ed.)
(2) DucpEn'IAux, E. I
1855. BUDGETS l~CONOMIQUES DEB CLASSES OUVRIERES EN BELGiqUE. Belg.
Min. Int., Bul. COllin. Cent. StaUs. 6: [261]-440.
(3) EDE:"l, F. M. 1797. THE STATE OF THE POOR. 3 v. London. (4) ENGEL, E.
1857. DIE VORHF.RRSCIIENDEN GEWEIIDSZWEIGE IN DEN GERIOHTSAMTERN MIT
BEZIEHUN(} AUF DIEl PRODUCTIONB- UND CONSUMPTIONSVERHALTNISSEl DES
KOz...GREICHS SACHSElN. Ztschr. StaUs. Bur. K. Siichs. Min. Inn., 3:
1899.
153-184.
(5) HUNT, C. L.
1918. A QUICK METHOD Oli' CALCULATING FOOD VALUES. Jour. Home Eeon.
10 : 212-218.
(6) LEPLAY, F. 185rt-79. LEa Om'RIERS EUBOPf:ENS. 5 v. Paris. ej) [~IAssAcnusE:rrs] BUREAU OF STATISTICS OF LARaR. ISi5. CONDITION OF WORKINGMEN'S FAMILIES. Mass. Bur. StaUs. Labor
Ann. Rpt. 6: [191]-450.
(8)
1886.
FOOD CO;:';SUMPTIO;:';.
QUANTITIES, COSTS, AND NUTRIENTS OF FOOD­
MATEIUALS. Mass. Bur. Statls. Labor Ann. Rpt. 17: [239]-326.
(9) ~.R.
•
:
1920. THm NATION'~ I'OOD. 274 P" ill1,1s. Pbiladelpbta';i1nilLondon,"
(10) ROSE; A.R '.
1920. .ABlUDGED DlETAR'f' CALCULATIONS! FOR RATIONS IN QUANTI'i."Y, Mod. . llosp. 14: 481-492.
,
(U) BOSE;' M~. S.
1921., A LABORATOl!.~ ~iANDBOOK FOR DIm'J!7litOS. Rev. ed., 156 p. lllus.
) J
"New York.
o
(12) SBEiWAN, H. C.
1926. OHm.nSTRY'OF
FCioD. AND NUXlUTION.
p., illU!!i New YorJ!i
Ed. 3, rewrltten and eIil., 63~
(13) TOOHER, J " . , r F . ·
. "
1925. VARIATIONS IN TI~E OOMPOSITION OF lIILX. 195"p., lllus. Edinburgh,
I
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