Fat (nutrient)

“ There is abundant proof that the body can manufacture fat even if there is none in the diet. Grazing cows that get no fat of any kind produce milk with its regular percentage of fat in the form of cream and do this day in and day out, showing that the fat that the body makes does not have to come from fat in the food. Since body fat represents ordinarily a storage of fuel against a future need, we ordinarily think of it as made whenever the temporary storage in the form of glycogen becomes inadequate to take care of the surplus of food over the amount consumed in carrying on the metabolism. ”

“ It is probable that the fat which is used in the body either to be stored away or for energy, is derived from other sources than directly from the fat eaten. From experiments made by Lawes and Gilbert on pigs, it is evident that the excess of fat stored in their bodies must be derived from some other source than the fat contained in their food, and must [62] be produced partly from nitrogenous matter and partly from carbohydrates, or, at least, that the latter play a part in its formation. It would appear from this that life might be maintained on starch, water, salts, and meat free from fat ”

“ Fats come from animal and vegetable sources and are represented by butter, fats of meat, olive oil, cottonseed oil, nuts and seeds. Oily substances are found in practically all vegetables. A vitamin known as fat soluble A is found in certain fats, but not in others. It is found in the fat of milk and usually in other fats of animal origin; and also in eggs and in leafy plants. Lard and oil of plant origin furnish very little of this vitamin. It can readily be seen by this that all fats do not have the same food value. ”

“ Our source of fat is chiefly animal food and in a smaller measure vegetables; but the fat our food contains is not altogether responsible for the fat in our bodies. Carbohydrates, if in excess of momentary needs, are partly converted into fat and stored as such. A reserve supply of nourishment is thus provided, and is drawn upon only when the food that we consume does not contain as much energy as we expend.
WHAT WE DO TO OUR FOOD.—With the exception of water and mineral substances, the food-stuffs must undergo chemical alterations before they are capable of being absorbed into the body ”

“ Weight for weight, fat furnishes twice as much heat as the carbohydrates, and in bulk the difference is even more striking; for example (about) two tablespoonfuls of sugar are required to produce 100 calories, whereas one scant tablespoonful of olive oil will produce a like number of heat units. As a source of supply for reserve energy in the body, fat is most valuable. This reserve fuel is stored in the form of adipose tissues underlying the skin and surrounding the vital organs, lending contour to the form and protecting the organs from jars and shocks. ”

“ Fat is especially important as a source of energy. It is possible to combine the fat and protein of animal foods so as to meet the requirements of the body with such materials only, and this is done in the Arctic regions, where vegetable food is lacking; but in general it is considered that diet is better and more wholesome when, in addition to animal foods, such as meat, which is rich in proteins and fats, it contains vegetable foods, which are richest in sugar, starch, and other carbohydrates. ”

“ For the sustenance of the body we must recognize that fat is fat, whatever its flavor. A calorie from butter yields neither more nor less energy than a calorie from lard or bacon, olive oil or cottonseed oil. The common food fats are all very well digested if judiciously used—not in too large quantities, nor over-heated in cooking, and not “cooked into” things too much as in pastries, rich sauces, and fried foods. Whether we spread our bread with butter or beef drippings amounts to the same thing in the long run; the main point is which we are willing to eat. ”

“ Ordinary animal fat, as has been shown in Lesson IV, is composed of various fats, each of which is a distinct chemical compound.
Human fat not identical with food-fat
The distinction between tallow, lard, olive-oil, and human fat, is chiefly due to the various portions of stearin, and olein, which composes the mixed fat. In normal cases, where fat is deposited at the usual rate, the body-fat is of uniform composition regardless of the food-fats. The reason human fat is not identical with food-fat is because the body has selective power in depositing these fats. ”

“ Our chief sources of fat supply are cream and butter, vegetable oils, nuts and the flesh of animals. Most meats, especially when mature, contain considerable fat. When the fat is mixed in with the meat, it is more difficult to digest than the lean flesh. Fresh fish, most of which contains very little fat, is digested very easily, while the fattest of all flesh, pork, is tedious of digestion.
There is an instinctive craving for fat with foods that contain little or none of it. That is why we use butter with cereals and lean fish, and oil dressings on vegetables. ”

“ The word "fat" is one of the most interesting in food chemistry. It is the great energy producer. John C. Olsen, A.M., Ph.D., in his book, "Pure Food," states that fats furnish half the total energy obtained by human beings from their food. The three primary, solid cooking fats today are:
There are numbers of substitutes for these, such as butterine, oleomargarine and "lard compounds." ”

“ It has been stated, however, that alimentary fat seems to preserve from destruction the fat of the organism which arises from other sources. Be this as it may, it is a fact that the pre-existence of fat furthers the accumulation of more adipose; or in other words, fat induces fattening! ”

“ This process is called hydrogenation, so named because the process is really one of adding hydrogen until the fat becomes saturated and less likely to undergo decomposition into fatty acid and glycerin. The fats thus formed seem to be equal to the animal fats so far as digestion and utilization are concerned, and hence are of considerable economic value at the present time.
Certain fats, including those of butter and milk, are rich in the so-called vitamines, and have been shown, by recent experiments upon animals, to be efficient growth stimulants. ”

“ When any one has been sick he is thin, because, to produce heat and power while he was sick, he has had to use the fat stored up in his body. To have such a supply of fat is like having a bank account to draw on when out of work. We might call the deposits of fat in our bodies our health banks.
Fat meat is not the only form in which we eat fats; we eat them in a great many other ways. Certain vegetables, [16] such as beans, contain an oil that forms fat. Ripe olives contain a great deal of fatty oil. Butter is a very important form of fat, and cream contains a large amount of it. ”

“ The principal constituents of fat, therefore, are carbon and hydrogen. Again, chemistry teaches that all food not consisting of flesh, such as vegetables, farinacea, sugars, &c., resemble fat, being chiefly composed of carbon and hydrogen; and, still more, that fat exists, already formed, in some vegetable substances, as oil of olives, oil of nuts, and oleaginous seeds. If, therefore, we introduce into the system substances rich in carbon and hydrogen, we must make fat as inevitably as the bee makes honey from its elements contained in the flowers. ”

“ The ideal diet determined by weight, height, occupation and general health of the individual contains just sufficient quantity of fat and carbohydrates to give the required amount of heat and energy. In popular terms, one-fifth of the diet should consist of fat. Much of this may be fat of vegetables or meats, but some of it should be butter fat or its equivalent, especially for children because of the vitamines it contains. ”

“ Butter, the fat of meats, olive oil, and the oil of nuts are the fats of greatest importance as foods. Fats, like the carbohydrates, are composed of carbon, hydrogen, and oxygen. They are rather complex chemical compounds, though not so complex as proteids. Since neither fats nor carbohydrates contain nitrogen, they are frequently classed together as non-nitrogenous foods.
Purpose Served by Carbohydrates, Fats, and Albuminoids.—These classes of nutrients all serve the common purpose of supplying energy. By uniting with oxygen at the cells, they supply heat and the other forms of bodily force. ”

“ The necessity of fat in the diet has been proven by numerous experiments. Animals lacking certain fats do not grow and cannot reproduce. Disastrous results have attended nations where shortage of supplies made it impossible to include the necessary fat in the diet. ”

“ The knowledge of the exact quantity of starch required for the formation of a given amount of fat is of importance in enabling us to estimate the relative feeding value of both substances. Certain difficulties stand in the way of our acquiring an accurate knowledge on this point. Not only are there several distinct kinds of fat, but the precise formula, or atomic constitution of each, is as yet veiled in doubt. There are three fats which occur in man and the domesticated animals, and in vegetables. ”

“ My theory of the cookery of fat is simply that heat, when continued long enough, or raised sufficiently high, effects an incipient dissociation of the fatty acids from the glycerine, and thus assists the digestive organs by presenting the base and the acids in a condition better fitted (or advanced by one stage) for the new combinations demanded by assimilation. Some physiologists have lately asserted that the fat of our food is not assimilated [159] at all—not laid down again as fat, but is used directly as fuel for the maintenance of animal heat. ”

“ Of animal fats, butter and suet are common examples. In vegetable form, fat is abundant in nuts, peas, beans, in various of the grains, and in a few fruits, as the olive. As furnished by nature in nuts, legumes, grains, fruits, and milk, this element is always found in a state of fine subdivision, which condition is the one best adapted to its digestion. As most commonly used, in the form of free fats, as butter, lard, etc., it is not only difficult of digestion itself, but often interferes with the digestion of the other food elements which are mixed with it. ”

“ Fat tends to retard gastric digestion, and delicate persons must be careful about taking with it other foods which are hard to digest, or taking it in the form of fried foods, pastries, rich cakes, and sauces. Persons with delicate appetite, who lose weight because they do not get enough fuel, may be benefited by taking a little more fat in the diet, especially if they do not digest starch and sugar readily, but a very large amount (over 6 or 7 ounces a day) will not be perfectly digested.
Fat as a food.—Beef fat, as it occurs with lean, is a digestible fat. ”

“ There is no struggle in this case between the several food constituents, and therefore no one of them suffers. In harmony also with daily experience the physician, in cases of weakness of the stomach, totally excludes fatty food and recommends meat of a fat-free kind; for example, game, etc. In pathological cases, however, where an excessive activity of the gastric glands is manifested, fatty food, or fat as emulsion, is prescribed. And here medicine has empirically brought to its aid the restraining action of fat, which we have so strikingly seen in our experiments. ”

“ On the other hand, those exercising little find that fat-rich foods distress them greatly, since they are too slowly digested. For many persons, the use of much fat is harmful. Since butter contains the fat-soluble vitamine, it is valuable not only for energy-giving, but for growth-promoting.
B. Food for Body-building and Repairing.—Both protein and ash are needed for body-building. The former foodstuff contains the element nitrogen,—one of the necessary elements for the growth and maintenance of the body. ”

“ The real mode of life and diet should be changed if the fat would be reduced. If necessary, procure a pair of scales and weigh the different foods that are taken into the system. Reduce the diet then to about four ounces of starch or sugar material per day, one and a half ounces of fat, taken chiefly in the form of butter, and about six or seven ounces of albuminous food, such as lean meat or fish. ”

“ It is an important point in the composition of oil-cakes, that they contain a large proportion of ready-formed fatty matters [191] which can, with but little alteration, be at once transmuted into animal fat. There are some individuals of the genus Homo to whose stomachs fat, per se, is intolerable; nevertheless, as a general rule, fatty substances exercise a favorable influence in the process of digestion, and, either in a separate state, or intimately commingled with other aliments, constitute a large proportion of the food of man. ”

“ A diet rich in fat, or in albuminates readily converted into fat, offers a favorable element for the absorption of fat by the healthy individual. If the organism demands but little of this fat for oxidation, as in the case of the sedentary person, an accumulation is likely to occur. This may become so considerable that obesity results. Tissues in which normally but little fat is accumulated may become infiltrated to a large extent. The intermuscular fibrous tissue thus becomes loaded, and the activity, as well as the nutrition, of the muscles is impaired. ”