ECONOMIC VALUE OF CERTAIN VEGETABLES. 
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ECONOMIC VALUE OF CERTAIN VEGETABLES. 
By Fred Stoker, M.B., F.R.C.S.(Ed.), F.R.H.S. 
[Being a short lecture delivered to the Acton Allotment Holders' Association, 
1917.] 
In the short time at my disposal it is manifestly impossible to go any- 
thing like fully into the subject of this lecture, so I must be content 
with, as it were, a few headlines which, if they serve to interest in 
this vast question, will be amply justified. I will endeavour to make 
my remarks as concise and practical as possible, and I will ask any 
critic to be indulgent, and keep in mind the difficulty of condensing 
the science of vegetable dietetics into a quarter of an hour's chat. 
A food may be defined as a substance which, when absorbed by 
the body, either supplies material to make good tissue-waste, or which 
supplies energy, or serves both of these functions. 
If a food stuff is analysed it is found to consist of : — 
Nitrogenous bodies — Proteids (Albuminoids). 
Carbohydrates. 
Fats. 
Mineral salts. 
Water. 
Of these the proteids, mineral salts, and water, acting together, 
can alone make good tissue-waste. 
The proteids also have another valuable property, viz. that of 
producing energy, which property they share with the fats and carbo- 
hydrates. In brief, then, the proteids are double foods in that they 
both make good tissue-waste and supply energy, while the fats and 
carbohydrates supply energy alone. 
It is therefore evident that proteids are indispensable, whilst the 
other two great groups, though of great advantage, can, on a pinch, 
be done without. 
There are substances in foods which are neither tissue-formers nor 
energy-producers, but which cannot well be dispensed with. I refer to 
the mineral salts and indigestible residue. The former are required 
for the body chemistry and the latter plays the important part of 
ballast — that is, a sufficient bulk of material to stimulate intestinal 
action. 
It is important to bear in mind that there are many substances in 
food which, although they consist of carbohydrate, fat, or proteid, are 
quite useless to the body, as the carbohydrate &c. are in an indigestible 
or unabsorbable form. The core of a pear is an illustration, or the 
rind of a pomegranate. 
