14 
LAND & WATliK 
M 
I V 
'7. 
iyi; 
(Table II.). The navvy, for instciiioe needs 5,200 raloiies. Tliise 
ligna^s arc- lor a .man wci{,'liing 11 stone, but sox, age. state, 
of liealtli and climate are all sinnilicant. Babies, for instance 
requin; relati\cly much more i)rotein to supply growth, aiitl 
more licat-(<iving food, because being small their skin surface 
^s relatively larger and therefore radiates more heat. A 
^lewbom baby nquires 100 calories for every kilo*, and in 
later life 70 calories (see Table III). A woman usually <ats 
about 08 of a man 8 ration, and in old age the heat iei\uir< 1 
may be reduced by 20 to 25 jier cent. Individual peculiantu s 
may not be verj' significant, but differences of build are nhist 
important. The short squat man has a much smaller icin 
surface than the tall spare man. The additional heat radiated 
accounts perhaps for the fact that tall thin people often ton- 
sume more food than others without getting any fatter 
Some correction, about 13 per cent., is also necessarj for 
the loss of food in cooking. Roughly, if 3,800 calorit^ are 
bought, 3,500 are eaten and 3,200 utilised by the bcxly. /The 
relative amounts of fat ;uk1 carbohydrate are largely a iiptter 
of taste, l>ecause they are interchangeable, both being oaiised 
in the body to the same substance. I'at is imleed lesspsily 
oxidised and absorbed, but it contains over twice the <iergy 
of carbohydrate, and the amount eaten in cold weather lay be 
increased with advantage. The fat supply of arctic aimals 
illustrates this heat-value, for the milk of the walrus ciitains 
ten times as' much fat as cows' milk. Also largely aiiatter 
of habit is the source of the protein. Thus the Asiaticlas ac- 
quired the habit of maintaining himself on a diet of ri<. For 
a European this would be as impossible as to liveon the 
purely carnivorous diet of the Eskimo. The amour 
tein usually consumed by an advilt is 100 grm. a 
children relatively require more (sec table III), 
liberal allowance and though the evidence is too co^ 
and controversial to l)e dealt with here, there car 
doubt that adults leading sedentary lives could re 
quantity to 60 grm. without harm, nay, even with jnefit. 
Nothing has yet been said with regard to thecheapest 
sources of protem and carbohydrate, or the best aprnatives 
to meat and bread. Full lists can be found in je workst 
mentioned below ; further details are not necessa 
Accessory Food Factors 
We have seen that a suitable diet must conin carbo- 
hydrate, fat and protein. But even when all thesJre present 
there may be lacking minute traces of certainubstances 
absolutely essential for growth, though not (ways for 
the maintenance of health and weight. Thesiubstances 
arc present in sufficient quantities in fresh Ilk, butter 
and vegetables, though actually the quaty is so 
small that it can hardly be determined. Thei bodies are 
known as " accesson,' growth substances," o sometimes 
'■ vitamines." \'ery little is known of th coniposi- 
tion or action except that their presence isssentialto 
all growth. This property has been shown in airy striking 
manner by feeding mice who have been inocited with a 
rapidly-growing cancerous tumour. After beinffd for some 
time on a diet free from the.se growth substancJhe tumour 
had scarcely grown at all, but when the moup\'as subse- 
quently fed on ordinary food, the tumour jr' in a few 
weeks to be nearly as large as the mouse itself. 
These growth substances are easily removed j he prepara- 
tion of food or destroyed in its manufacture, h interesting 
to learn that our soldiers, operating in count where the 
provisions are necessarily almost entirely tinnPr otherwise 
jireserved, are given a dried extract of yeastpemely ricli 
in the substances that are deficient. 
A striking ex.unple of the necessity of thcsfcessory sub 
stances is found in the case of natives who feJxclusively on 
white rice polished by machiner\'. They suftJom a disease 
called ben-beri, a form of neuritis which can bjred either by 
. the substitution of a mixed diet or by the additpf the husk of 
the rice wliicli contains the substance in cpiesti^n this respect 
war bread is superior to white bread in that f ntains a large 
percentage of " offal." Scurvy is caused fbe lack of a 
similar factor, as was well known by Captaipok and other 
explorers, •whose custom it was to cure theien by admini- 
* A kilo — 2-2 lbs. 30 grams = t oz. 
t Those who wish to obtain further informal 
suit the following works, to which the author 
figures quoted : 
J'amy'-i--- "•• ■■" '■■■"1-viJue : — 
J lime. ByT. B. Wi 
J' nj Dietetics. By R, 
liuliehti, Ao. if>. — C.S. Oept., of Agritultui 
Food Value!:, what they are and how to ci*c them 
McKillop. 
Books on NutriUon :- — 
77 ■ ' '•• • ' ' Ilofii ,./ Kidnhoii. By rf'" Lusk. 
A. By Chittenden. 
7/ , Food and }icononi\ in JCt^V W. M. 'R.-vvIi^s 
The Vhysioiifgy 0/ Protfin Mftaiiolism. B»'- Cathcart. 
ndvLsed to con- 
icbted for many 
d F. G. Hopkins, 
liison. 
-shington. 
By.M. 
stenng an infusion Of pine-needles or any other green plant 
available. It has been suggested that" even rickets and 
pellagra may be due to a like cause. 
Jinally, there are certain substances lousuly ctjlled. stimu- 
lants which are principally derived from meat. These are 
the extractives, etc., present in meat juice. They can, for 
mstance, .stimulate the flow of the gastric juices and excite: 
the appetite. It is in this way that they are important in 
the diet of invalids. The mere sight and .smell of foixl, if 
well sen'ed and of appetising appearance, is similarly of great 
importance in stimulating by a psychologies process the 
involuntary mechanism that regulates the digestive juices. 
Overeating and Starvation 
The ill-effects of overeating are not at present so serious as 
the great waste it entails. It mav be thought that an excess 
"I food eaten one day may be utilised later, l^nfortunately, 
the body lias a very limited power of storage. A little carbo- 
hydrate accumulates in the liver as glycogen and fat is <le- 
jxisited as adipose tissue, but protein cannot be stored at all. 
V\ hen the energy requirements of the body have been supplied 
what IS to become of the excess food consumed by the ' good 
healthy appetite " so often and so erroneously praised ? As 
It cannot be stored the onlv alternative is to bum it away as 
soon as possible. This wasteful and perhaps harmful over- 
production of heat is going on without doubt in nnst of us 
who do not do heavy muscular work, so that at present we 
coukl reduce our food nearly one-third without harm and 
probably with considerable benefit to ourselves. 
In the event of starvation, the reserve of glycogen is used 
first ; next, the fat is consumed, and then if ncj other food is 
available, the protein of the body itself. In this process 
It IS the muscles that sufier most and characteristic wasting 
commences. If starvation is complete, finally the vital organs 
are used and death ensues. The first effects of starvation^ 
m the degree to which it is no doubt at present being ex- 
perienced in Germany, is a decreased output of work— the 
effect obviously of a lack of fuel. This is probably accom- 
panied by a lowering of the body's resistance to disease, and 
together they may have very serious results. 
Clearly, therefore, a man may exist for some time by con- 
suming his own body, and this he frequently does in disease. 
Very often one has heard how an invalid has been kept alive 
for many days on beef tea or meat juice. As a matter of 
fact, It was his own fat and muscles he was Uving on, for 
there is no food value in such substances, though they may 
.stimulate flow of gastric juices and the appetite. It would, 
in fact, require ten pints of the best beef tea or a pound of 
concentrated Bovril to supply the protein for one day, and 
animals fed on J.iebig's extract soon starve to death. 
It has even been said that " all tht; bloodshed caused by 
Napoleon is nothing to the number who have died from a mis- 
placed confidence in beef tea." Invalids are often very un- 
fortunate in their choice of food. Arrowroot, for instance. 
IS believed to be very " nourishing." whereas m reality it i- 
devoicl of body-building material and only suppUes heat. The 
same is true of cornflour or tapioca. There are many similar 
fallacies the reader can no doubt supply himself, and it is to 
be hoped that myths such as the use offish for " brain food " 
or blood in ana-mia are no longer belie\-cd b>- anybody. 
(,i>.i > aioru's ])i'i' 
T.IlBle I. 
Kadiation from the clothed bodv 
hour) . . . . _ ' 
Evaporation of water at skin and itings . . 
1 leating of respired air 
Heating of food and drink to body temperature 
Work of heart and lungs . . 
Two hours walking . . 
'J'otal 
Tai'.ii ff. 
Professional men .^ 
Farmers . . 
Klacksmith or na\'\'y . . 
Kider in six-dav bicycle radc 
Child under a years? 
„ .3 to 5 years 
„ to 9 ., 
„ 10 to 13 „ 
Girl 14 „ Ki „ 
Tioy n ,, ifi ,, 
Woman ^ ^ 
Table III. 
T(ital 
Calorics. 
1050 
1400 
1 750 
_ 2100 
- 2450 
2800 
- 2.S00 
Total 
Calories. 
2700 
5200 
10000 
C.rani,<; 
Protein. 
70 
71 
79 
alories. 
i.'i.V' 
01 I 
S.) 
27" 
Calorics 
jxT kilo, 
.3« 
.so 
7.5 
Per cent, 
of farmer's 
diet. 
0-3 
0-4 
o'5 
o-i. 
0-7 
0-8 
0-8 
