Encyclopaedia Britannica > Volume 8, DIA-England

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DIETETICS.
Dietetics, might be divided into the azotized, hydrogenous, carbona-
ceous, and oxygenous, or rather rnto those which supply
abundantly azote, hydrogen, carbon, and oxygen. This
view is, however, chiefly theoretical, as we are very far
from possessing facts enough to establish it completely, or
to overturn it; but yet there are some which favour it. We
have already noticed Magendie’s experiments on substan¬
ces which do not contain azote, from which he inferred
that a certain supply of it was absolutely necessary to the
support of animal life. Other facts lead to the same con¬
clusion, especially the effect of restriction to one kind of
aliment in the generation and cure of disease.
It is many years since Dr Rollo1 was led, by the singu¬
lar sweetness of diabetic urine, to conclude that, if he de¬
prived the patient of all food which contained sugar, or the
principles of sugar, he should be able to cure this hither¬
to untractable disease. He accordingly restricted his pa¬
tients to the use of animal food, especially fat, and abso¬
lutely prohibited all vegetables, even bread, and all fer¬
mented liquors. The effects were very striking, and some
patients were believed to be cured; at least the nature
of their urine was completely altered from a morbid to a
healthy state. As conducted by others, the same regimen
has produced the same effects ; but it is so disagreeable to
the patients that they can seldom be prevailed upon to
adhere to it, and unfortunately, notwithstanding the tem¬
porary removal of this prominent symptom, the disease
generally continues its fatal course. We may, however,
notice, that Rollo and others were guided in their choice
of regimen by the principle of withholding the elements
of sugar, and hence fat formed a chief part of it, and was
a principal cause of the disgust it excited; but perhaps it
would be better to select a highly azotized diet, in which
point of view the muscular parts of dark-fleshed animals,
such as game and old mutton, and those kinds of fish, such
as skate, which contain much azote in a loose state of com¬
bination, should be selected; while wheaten bread, the
want of which is so distressing to many, might be allowed,
and fat, which contains no azote, should not be prescribed.
Magendie2 ascribes the gravel to the superabundance of
azote in our food, as the uric acid of which gravel consists
is a highly azotized substance, and seems to be produced
as a means of throwing off the excessive azote ; and among
the various causes with which gravel is connected, the
most active in its agency is high living, or the use of ani¬
mal food in excess. A Hanseatic citizen, who kept a good
table previous to 1814, was afflicted with the gravel. He
emigrated and lived very miserably in England, but his
gravel completely left him. He re-established his affairs,
and with his fortune his gravel returned. Again he was
ruined, and went to France almost destitute, and his gravel
disappeared. By industry he finally acquired a compe¬
tency, and with it his old complaint, for which he then
consulted Magendie. A Parisian lady of sixty, subject to
gravel, read in a journal a short notice of Magendie’s ex¬
periments, in which it was said that he had discovered in
sugar a cure for the gravel. Without more advice she set
about eating sugar, often to the extent of a pound daily,
and in effect she removed the gravel, but disordered her
stomach so much that she was obliged to resume her usual
food, and with it the gravel returned.
The chemical theory of the scurvy is, that it is owing Dietetics
to the want of oxygenous food; and it cannot be denied ''-"Y'w
that this theory has been very ingeniously supported by
Dr Trotter, Dr Beddoes, and others. The rapidity with
which those afflicted with it recover by the use of recent
vegetables, especially the fresh citric acid, shows that it
proceeds from an error in diet, but whether from a defi¬
ciency of nourishment in general, or from a deficiency of
oxygenous aliment, is not quite so clear. When we com¬
pare the accounts of the ravages formerly committed by
this dreadful disease, even during short voyages, with the
almost total immunity which the British fleet has enjoyed
since the time of Captain Cook, we have the strongest
possible proof of the influence of diet upon the human
frame, either as inducing or preventing disease.3
Hydrogenous food, such as the excessive indulgence in
fat meat, butter, and oil, and still more especially in spi¬
rituous liquors, produces a change in the chemical consti¬
tution of our bodies, independently of the exhaustion of
excitability by excess of stimulus. Bilious diseases, and
a tendency to unwholesome fatness, are its most common
effects; and it is only in the excessive hydrogenation of
the system that we can find a rational explanation of that
very singular phenomenon called the spontaneous combus¬
tion of the body; for even admitting that the clothes are
accidentally set on fire in these cases, there appears no
reason to doubt that the combustion is continued by the
burning of the body itself. Now the greatest number of
instances have occurred in old women addicted to the
abuse of ardent spirits.4
The effects of oxygenous food, in imparting oxygen to
the body, are not so well ascertained. Acids, and the
subacid fruits, quench thirst, and are supposed to reduce
animal heat; but their more obvious action is to affect the
bowels and induce diarrhoea, and ultimately to render the
body spare and thin. The new chemical pathology led to
the exhibition of nitric acid for the cure of syphilis, as
mercury was supposed to act by oxygenizing the system ;
and this acid has since been much employed also, from
analogy, in the liver complaint. That the acid has excel¬
lent effects as a tonic, seems to be perfectly ascertained.
It does not act upon the bowels like the vegetable acids,
but there is no proof of its decomposition in the stomach,
or of its imparting oxygen to the bod}r. The oxygenizing
of the system by means of the nitro-muriatic or oxymu-
riatic bath, now so fashionable in London, is a mere chi-
Pulmonary consumption was also, at one time, con¬
sidered as a disease proceeding from superabundant oxy¬
gen, and the florid colour of the cheeks was adduced in
proof of it.
No observations have yet been made on the effects of
aliments containing an unusually large proportion of car¬
bon, nor has any disease been ascribed to the carboniza¬
tion of the system.
It would extend this article much beyond the space we Peculiar
can allot to it, if we were even hastily to sketch the va-species o
rieties of diet recommended in disease, and to explain regimen
their action ; but it will not be superfluous to enter a little ca . .
into the detail of that kind of regimen which has been Tral'm*'
found by experience to bring animals and man to tbe
highest possible state of health, at least as measured by
1 An Account of two Cases of Diabetes Mellitus. By John Rollo, M. D. 2 vols. 8vo, London, 1747.
2 Recherches Physiologiques et Medicales sur les Causes, les Symptomes, et le Traitement de la Gravelle, 8vo, Paris, 1818.
3 Observations on the Scurvy. By Thomas Trotter, M. D. 8vo, Lond. 1792. Observations on the Nature and Cure of Calculus,
Sea Scurvy, Consumption, Catarrh, and Fever; together with Conjectures upon several other subjects of Physiology and Pathology.
By Thomas Beddoes, M. D. 8vo, London, 1793.
4 An Essay, Medical, Philosophical, and Chemical, on Drunkenness, and its Effects on the Human Body. By T. Trotter, M. D.
8vo, London, 1804. Essai sur les Combustions Humaines produits par une long abus des liqueurs spiritueuses. Par Pierre-Aime
Lair, 12mo, Paris, 1801.