CONDITIONS TO BE OBSERVED BEFORE AND AFTER EATING.
General laws of organic activity apply to the stomach as well
as to other parts--Increased flow of blood towards the stomach
during digestion--Hence less circulating in other organs--And
consequently less aptitude for exertion in them--Bodily rest
and mental tranquillity essential to sound digestion--Rest
always attended to before feeding horses--Hence also a natural
aversion to exertion immediately after eating--Mischief done by
hurrying away to business after meals--Severe thinking hurtful
at that time--Playful cheerfulness after dinner conducive to
digestion--The mind often the cause of indigestion--Its mode of
operation explained--Also influences nutrition--Illustration
from Shakspeare.--Importance of attending to this condition of
health enforced.
Having now discussed the principles by which the number, quantity, and
quality of our meals ought to be regulated, we have next to consider
the conditions required for the healthy performance of digestion after
the aliment has reached the stomach, and to deduce from them such
practical rules as shall tend to facilitate the accomplishment of the
process.
Among the circumstances which favour digestion, _the observance of
bodily rest and mental tranquillity for some time before and after
every meal_, is perhaps the most important; its influence depends on
a well-known law of the animal economy, already frequently alluded to,
but to which, that it may be fully understood, I must again shortly
refer.
Whenever any living part is called into vivid action, an increased flow
of blood and of nervous energy towards it immediately commences, to
enable it to sustain the requisite degree of excitement, and continues
till some time after the activity has ceased. In accordance with this
law, whenever food is swallowed, the lining membrane of the stomach
becomes suffused with blood, and, owing to the greater distention of
its vessels, its colour changes from a pale pink to a deep red hue.
After digestion is completed, and the unusual supply of blood is no
longer required, the vessels again diminish, and the colour returns
to its original tint. In St Martin’s stomach, these changes were so
often seen by Dr Beaumont, as to render their occurrence as fully
demonstrated as any circumstance with which we are acquainted. Even
had they never been seen, the simple examination of the structure of
the stomach would lead us directly to the inference that it receives
an additional supply of blood when engaged in digestion; for the very
act of its distention by food renders the course of its bloodvessels
less tortuous, and the flow of blood through them consequently more
easy and rapid. In the case of the stomach, indeed, the increased
circulation is doubly required; not only as in other parts to enable
it to act with greater vigour, but also to supply the very copious
secretion of gastric and mucous fluids necessary for digestion, and
which we have seen to commence the moment food touches the mucous
coat. The quantity of gastric juice actually secreted at each meal
cannot easily be determined; but as more than an equal weight of it
is required for the solution of food out of the stomach, its amount
must be very considerable. Indeed we know that, on one occasion, when
St Martin dined on broiled mutton and bread without any liquids, the
gastric secretion was so copious, that half an hour afterwards the
“stomach was as full of fluids as when he drank a pint immediately
after eating;”[55] and, as the whole of this must have been derived
directly from the blood circulating through the vessels of the stomach,
they must necessarily have received a very large supply to enable them
to furnish it.
It is obvious, however, that the great afflux of blood which takes
place towards the stomach and intestines during digestion, cannot
occur without a corresponding diminution in the quantity circulating
on the surface and in other distant parts of the body, attended of
course with a diminished power of action in them. Hence, for some time
after a full meal, there is an inaptitude for vigorous thinking and
bodily exertion, a depression of respiration, and, in delicate persons,
a degree of coldness or chill felt over the whole body. But, under
ordinary circumstances, this depression is not of long continuance.
After the requisite secretions have been provided for the solution of
the food and the formation of the chyle, a reaction and change in the
distribution of the blood, now partially renewed by the admixture of
nutritive chyle, ensue, and, by the stimulus which they afford, soon
fit the person for the active resumption of his ordinary duties.
That this impaired activity of the other functions after a full meal
is natural, and intentionally arranged by the Creator, is plain, both
from its universality among all kinds of animals, and from the mode
in which it is produced. Among the lower creatures, the sluggishness
induced by eating increases in proportion to the degree in which they
gorge themselves with food. The boa constrictor, after a plentiful
repast, slumbers for a week; and the glutton of our own species, in
similar circumstances, drops into a stertorous sleep of several hours.
If active exertion immediately after a full meal be rendered compulsory
by any external cause, such as the presence of danger urging to flight,
the aliment often remains for hours in the stomach undigested. Again,
the very distention of the stomach inseparable from a hearty meal,
_necessarily_ impairs the activity of several of the functions,
by directly pressing upon the vessels which supply their organs with
blood, and consequently diminishing the stimulus essential to their
activity.
The obvious practical inference to be deduced from a consideration of
the principle under discussion is, that rest of body and tranquillity
of mind for a short time both before and after eating are necessary,
and conducive to healthy digestion. If we have been engaged in severe
and fatiguing bodily exertion, or anxious meditation, just before
sitting down to a meal, the blood which was flowing copiously through
the vessels of the muscles or the brain to keep up their unusual
action, still continues to do so, because a sufficient interval has not
elapsed to allow the excitement to subside, and a new distribution to
take place towards the organs concerned in digestion. The consequence
is, that the stomach does not receive blood enough to carry on its
increased action, and furnish gastric juice with sufficient rapidity,
or in sufficient quantity, to mix with the whole of the food; and that
the nervous energy, already partially exhausted by over-excitement
in the remoter organs, is imperfectly supplied to the stomach, the
tone and action of which are thus so far impaired as to render it no
longer able to carry on digestion with its usual success. Accordingly,
when we are fatigued with mental or bodily labour, we are naturally
impelled to seek repose before sitting down to table; and if we yield
to this instinctive prompting, and refresh ourselves by a rest, we not
only enjoy better what we eat, but also digest it with an ease and
comfort unattainable by swallowing our food the moment our labour is
at an end--and hence the wisdom and advantage of appropriating half an
hour to any light occupation, such as dressing, before sitting down
to dinner. If, however, we have previously been engaged only in very
moderate exercise, an interval of repose is not required, because then
there is no undue excitement elsewhere to retard the necessary flow of
blood and nervous energy towards the internal organs.
The practical rule of avoiding serious exertion of mind or body
immediately after eating, which is directly deducible from the
physiological law above explained, has long been acted upon in our
treatment of the lower animals; and no one who sets any value on the
lives of his horses or dogs, ever allows it to be disregarded with
respect to them. And yet the same man who would unhesitatingly dismiss
his groom for feeding his horse immediately after a fatiguing chace
or a gallop home, would probably think nothing of walking into the
house and ordering dinner to be instantly served for himself in similar
circumstances. In the army, the difficulty of managing recruits on a
march, in this respect, has often been remarked. Fatigued with the
day’s exertions, they are impatient for food, and, when they get it,
can scarcely refrain so long from devouring it as to admit of its
being even moderately cooked. They consequently labour under the
double disadvantage of eating before the system is in a sufficient
state of repose to benefit by the supply, and of having the food
itself in a condition unfit for easy digestion. The old campaigner,
on the other hand, instructed by former experience, restrains his
appetite, systematically kindles his fire, cooks his victuals, and
makes his arrangements for the night, with a coolness of deliberation
which surprises the recruit; and he is amply repaid for his temporary
self-denial, by the greater enjoyment and support which he derives from
the very same materials which the impatience of the other has caused
him in a great measure to waste.
Let any one who doubts the advantages resulting from attention to this
rule, consider for a moment its universal and scrupulous observance by
postmasters and jockies, and think whether these are persons likely
to throw away time and trouble on a useless ceremony. When a horse is
taken out of harness, an interval of repose is always allowed, that the
excitement of the system may have time to subside; and then not only
an eager appetite but an active digestion are sure to follow. Many a
valuable horse has been killed by being prematurely fed after fatiguing
exercise, and man himself is no exception to the rule. He not only
enjoys a meal with superior relish, but digests it better, when due
repose has removed the fatigue and excitement of exertion. Even after
continued activity of _mind_, a period of tranquillity or of
gentle bodily exercise is eminently conducive to the healthy action of
the stomach, precisely because it favours the new distribution of the
circulating blood which that process requires.
In accordance with this law of digestion, there is throughout the
whole animal creation a marked aversion to activity for some time
after a full meal, although man, eager in the pursuit of gain or the
gratification of other passions, often sets it at defiance, and engages
in bodily or mental labour both immediately before and after meals;
but, in return, he receives his reward for despising the authority
of Nature, in a severity of suffering from which the animals whom he
treats so much better than himself are by his care entirely exempted.
No where, for example, does man hurry off to business so immediately
as in the United States of America, and no where does he bolt his
food so much as if running a race against time. The consequence is,
that no where do intemperate eating and dyspepsia prevail to the same
enormous amount. Even in England, according to Dr Caldwell, the extent
of transgression cannot be compared with what is witnessed among our
Transatlantic brethren; and the result shews, that if we in Britain
suffer from indulging our fondness for good things, the comparatively
deliberate way in which we set about enjoying them serves as a partial
safeguard, and exempts us from a portion of the punishment which our
brethren bring down upon themselves, by the hurry with which they
first devour their food and then set off to work. Rapid eating almost
invariably leads to overloading the stomach; and when to this is added
a total disregard of the quietude necessary for digestion, what can be
expected to follow but inveterate dyspepsia?
The reason why wounds, bloodletting, bathing, and other circumstances
which tend to disturb the regularity of the circulation, are so
hurtful after a full meal, will now be apparent. The effect of wounds
and bloodletting is to give rise to an instantaneous change in the
distribution of the blood, and to deprive the stomach of that which is
now doubly required. Bathing, whether hot or cold, has an analogous
effect; and so, indeed, have all violent and sudden bodily or mental
shocks.
It must not, however, be imagined that the period of repose necessary
to insure healthy digestion extends over the whole time of the
continuance of food in the stomach. After a moderate meal and in
ordinary health, the concentration of the vital powers in that organ,
and their proportionate depression in other parts of the body,
rarely continue, at least in a very marked degree, beyond the period
usually allotted to the _siesta_, or sleep after dinner, in warm
climates, and even in Italy and Spain--namely, an hour or an hour and
a half. When the meal has not exceeded the bounds of moderation, _a
sufficient quantity of gastric juice for the digestion of the whole
is secreted generally within the first hour_; after which time,
consequently, the same quantity of blood is no longer required to be
directed towards the stomach, but may beneficially be distributed to
such other parts as from their activity more immediately require its
aid. If the muscular system is to be employed in labour or locomotion,
the blood can now be spared to sustain its activity; if the mind is
to be engaged in intellectual pursuits, it can be sent to the brain
without robbing the stomach. The same principle of course applies to
all the other organs; and it is therefore chiefly during the first
hour, till all the gastric juice be provided and the chymification of
the food be fairly commenced, that tranquillity of mind and inaction of
body are so essential.
As already mentioned, the reality of increased circulation in the
vessels of the stomach during digestion has been established by ocular
demonstration, as well as by analogy. The increase in the supply of
nervous energy which takes place at the same time is, however, scarcely
less certain, although from its nature incapable of being seen. It is
the almost characteristic feature of the nervous system to be excited
by stimulus to increased action; and we formerly saw that when the
nerves of the stomach are cut, and the flow of nervous influence is
arrested, digestion instantly suffers. But the same principle holds
in the nervous as in the circulating system. Energetic action cannot
be kept up in two distant parts of the body at the same time. If the
intellect be intently occupied in profound and absorbing thought, the
nervous energy will be concentrated in the brain, and any demands made
on it by the stomach or muscles will be very imperfectly attended to.
If, on the other hand, the stomach be actively engaged in digesting a
full meal, and some subject of thought be then presented to the mind,
considerable difficulty will be felt in pursuing it, and most probably
both thought and digestion will be disturbed. If the mental effort
required be easy and agreeable, and the meal be a very temperate one,
there will be much less difficulty in simultaneously proceeding with
both, because comparatively little nervous energy will then suffice
for them. Still, however, each will go on more efficiently if not
interfered with by the other.
When the mind is active and vigorous, and properly exercised in all
its departments of feeling and affection as well as of intellect, the
nervous influence which the brain produces is not only more abundant,
but of a more healthful and invigorating quality. Hence the well-known
preservative and restorative influence of cheerful dispositions and
gratified activity of mind, and hence the depressing, morbid, and
often fatal effects of corroding care, grief, and apprehension, on
every organ of the body. Hence, too, the weak digestion and sallow
complexions of literary men and hard students, who suffer severely from
transgressing this law of the animal economy by habitually engaging in
occupations requiring much exertion of mind, not only soon after, but
even during the very act of swallowing their meals. Ignorant of the
connexion subsisting between the different functions, and of their laws
of action, few can be convinced in time of the importance of observing
this condition, even after its operation has been explained to them.
In the conclusion, however, experience teaches many whose reason is
insufficient for their guidance, and forces them to a closer conformity
with the dictates of nature, when obedience is almost too late to be of
benefit.
The prodigious influence of the nervous system on digestion is
familiarly and unequivocally exhibited in almost every case of
dyspepsia which each succeeding day brings under the notice of the
physician. _He_ knows well from experience that the diet may be
selected with every care, its quantity duly proportioned, and exercise
rigidly practised, and yet all his curative treatment fail even to
relieve, unless his patient be at the same time freed from the pressure
of care, and due attention be devoted to the observance of mental and
bodily repose after every meal. The heavier the meal the greater is
the desire for absolute rest, and the less advantageously can active
exertion be encountered. When the stomach is loaded, the whole vital
energies seem to be concentrated in it to enable it to cope with the
task imposed upon it. But when we eat temperately, there is less
necessity for entire quietude of mind and body. Accordingly, if we do
not experience the same dislike to exertion after a light forenoon
lunch, which we do after a heavy late dinner, the reason is simply,
that less gastric juice, less nervous energy, and less vigorous action
in the stomach, are required to digest in the one case than in the
other.
Among operative manufacturers, who are much within doors, and who are
allowed only a few minutes for meals, indigestion is very prevalent.
Ordinary labourers are better treated in this respect, as they are
allowed one hour for breakfast and another for dinner. To most of them
the walk to and from their own houses is almost as good as, if not
better, than absolute rest, because it varies their position, is taken
leisurely, and costs no effort.
Those who are compelled by circumstances to active exertion
immediately after a meal, or whose minds are intently occupied in
thought or emotion, will find their only safety in eating less than
when differently situated. The stomach, having less labour imposed upon
it, will require less blood and less nervous energy, and consequently
less of both will be abstracted from the other organs which are also
in activity, and requiring their assistance. Travellers, literati, and
other actively engaged men, know this rule by experience, and some of
them have specially noticed its importance. Richard Cumberland, for
example, in speaking of his own habits, says: “Nature has given me
the hereditary blessing of a constitutional and habitual temperance,
that revolts against excess of any sort, and never suffers appetite
to load the frame. I am accordingly as fit to resume my book or my
pen the instant after my meal as I was in the freshest hours of the
morning.”[56] This compatibility of temperate eating with activity did
not escape the acute observation of Hippocrates.
The state of the mind, indeed, exerts a powerful influence not only
on the stomach, but on the whole process of nutrition, and greatly
modifies the quantity which may be safely eaten. If the mind be gay
and joyous, appetite will be comparatively keen, digestion effective
and rapid, and nutrition complete. Examples of this kind abound in
childhood, and among an easy-minded well-fed peasantry; whereas if
the mind be harassed by care and anxiety, or devoured by grief, envy,
jealousy, or other troubles and disquieting passions, the healthy calls
of appetite will be scarcely known, and digestion and nutrition will
be equally impaired, for it is literally true that “indigestion or, to
use the term of the day, a _Bilious attack, as often arises from over
exertion or_ ANXIETY OF MIND, as from refractory food.”[57]
This fact is exemplified on a large scale in every commercial country,
and especially in times of _public distress_ and _political
change_. Shakspeare obviously had the principle in view when he made
Cæsar exclaim:
“Let me have men about me that are _fat_,
_Sleek-headed men_, and such as sleep o’ nights.
Yond’ Cassius has _a lean and hungry look_;
_He thinks too much_: such men are dangerous.
_Antony._ Fear him not, Cæsar, he’s not dangerous;
He is a noble Roman, and well given.
_Cæsar._ _Would he were fatter_:--But I fear him not:
Yet if my name were liable to fear
I do not know the man I should avoid
So soon as that spare Cassius.--He reads much.
He is a great observer, and he looks
Quite through the deeds of men; _he loves no plays_
As thou dost, Antony; he hears no music,
Seldom he smiles, and smiles in such a sort
As if he mocked himself, and scorned his spirit
That could be moved to smile at any thing.
Such men as he be never at heart’s ease
Whiles they behold a greater than themselves,
And therefore are they very dangerous.”
Even experience must have taught every one with what zest we sit down
to enjoy the pleasures of the table, and how largely we incline to eat,
when the mind is free, unburdened, and joyous, compared with the little
attention we bestow on our meals when we are overwhelmed with anxiety,
or have the whole energies of the mind concentrated on some important
scheme. There cannot be a doubt, indeed, that the over-exertion and
excitement, or absolute inertness, of mind, in which sedentary people
are generally immersed, contributes greatly, along with the want of
muscular exercise in the open air, to impair the tone of the digestive
organs. In this way, as it is not less justly than forcibly remarked
by Dr Caldwell, “dyspepsia _commences_ perhaps as often in the
brain as in the stomach. Possibly oftener. That this is true of the
disease in Europe will scarcely be denied, after a fair examination of
the facts connected with it. It is there almost exclusively a complaint
of the studious and the scheming, who, over-tasking their brains,
injure them by toil. Among the husbandmen of England, who steadily
pursue their tranquil mode of life, regardless of the fluctuations of
stock, the bickerings of party, the fate of political measures, and
the changes of place, dyspepsia is almost a stranger.” “In the cities,
the same is in a great measure true of merchants, manufacturers, and
mechanics, who are engaged in a regular and well established business,
which is fully understood by them, where the risk is slight and the
profits sure, and no disquieting anxiety attends it. Such individuals
have a good digestion, and bear the marks of it. But with literary men,
officers of state, dealers in scrip, daring adventurers, and anxious
and ambitious projectors of improvements, with these and every other
brain-worn class of persons, the case is different. Dyspepsia is their
torment, and they exhibit deep traces of it in their lean frames and
hagard countenances. Yet are they much more select in their diet,
both as respects quantity, quality, and cooking, than the classes to
whom dyspepsia is unknown. This fact is notorious, and has been so for
centuries. Nor can it be attributed, I think, to any other cause but
excessive and deleterious cerebral irritation in the one case, and an
exemption from it in the other; and this cause seems sufficient to
solve the problem.”[58]
In denouncing active exertion of mind or body immediately after
eating, as inimical to digestion, it is not meant that we should go
to sleep, or indulge in absolute listlessness. A weak constitution
may require something like complete repose, but a person in ordinary
health may indulge in a leisurely saunter or pleasant conversation
not only without injury but with positive benefit; and perhaps there
is no situation in which digestion goes on so favourably as during
the cheerful play of sentiment in the after-dinner small-talk of a
well-assorted circle. The nervous stimulus sent to the stomach is
then of the most healthful and invigorating description, and ever the
dyspeptic, if on his guard against a heavy meal, forgets his woes
amidst the unwonted vigour of his functions.
It is true that thousands who habitually neglect the observance of
the condition here adverted to, continue to live and digest for years
without appearing to suffer much from their conduct. But it is not
less true that there are many more who bring wretchedness and disease
upon themselves and their offspring, in the vain attempt to counteract
the intentions of Nature, and that there are comparatively few even
of the former so happily constituted as to escape entirely unscathed.
Most frequently the evil consequences are only accumulating, and when
they are summed up at the end of years, the victim finds himself more
severely punished than he had ever expected to be. In this respect,
the consequence resembles that arising from breathing in a vitiated
atmosphere. The effect may not be perceptible for a time; but if God
has ordained a pure air to be best adapted for respiration, we have the
infallible authority of His omniscience for believing that one which
is vitiated _must_ be less wholesome, although His beneficence
has so constituted us, that the injury resulting from it is gradual
in its infliction, for the very purpose of giving us time to escape.
In like manner, if bodily and mental relaxation are favourable to
digestion, we have the same infallible guarantee that every departure
from them _must_ be in so far hurtful, however slowly the effect
may develope itself.