Meat is the commonest animal food, is the most nutritious, and most closely resembles in its composition our own bodily tissues. Because the albumin of meat is much better absorbed than any other kind of albumin, such food can replace wasted body elements in a shorter time than can any other kind of nutriment.

Even the albumin of milk leaves more residue than that of meat. From this latter, therefore, is derived the most benefit during the period of bodily growth, or in the other conditions above mentioned; but it will not be so efficacious in those whose growth is already finished, or whose body tissues are wasted by disease or by other demands on them.

Meat contains very valuable nutritive elements, such as large quantities of proteids and fat, but very little carbohydrates; also various important salts, such as chlorides, phosphates, and carbonate of potassium. Meat also contains iron, the largest amount being found in the blood of pigs. We can estimate the nutritive value of different kinds of meat from the following table; according to Professor Rubner,^[263] each 100 parts contain:—

In addition to the above nutritive elements there are also a series of extractive substances to which is due the pleasant taste of the meat. When such food is boiled these substances and salts pass into the water, and such meat loses in flavor, though not in its nutritive qualities, for the water i.e., the soup is not nutrimental at all. Meat, if prepared for the table directly after the animal is killed, would not be palatable; and it is, therefore, necessary for it be kept for a given time before it is eaten. Dr. Wiley, of Washington, considers that meat improves if kept not exceeding fourteen days in cold storage, after which time it begins to lose its best qualities.

When meat is chilled it does not lose its pleasant taste; but when it is frozen the case is very different, for then it loses its beneficial juices, which escape into the surrounding ice. In such meats, therefore, the extractives which give the pleasant flavor are wanting. Refrigerated meat generally arrives in Europe in excellent condition from America.

Before animals are slaughtered to be used for food a rigorous examination by veterinarians must be made, in order to avoid poisoning from meat in a condition of putrefaction, or from diseased animals. Some animals, such as pigs, very often suffer from acute inflammatory diseases caused by catching cold while on long journeys prior to being slaughtered. Fortunately, in the early stages of such illness there is little danger, for it can be avoided by thorough bleeding. The Jewish method of bleeding an animal is thus particularly to be recommended, for by this means poisonous products can leave the animals’ bodies in large quantities. Meat retaining all the natural blood decomposes very rapidly, especially in hot climates, and we must not forget that such poisonous substances, as ptomaines, in meat, are not destroyed by the process of cooking.

The greatest danger from poisoning lies in oysters, which are otherwise a most digestible food. This is owing to the frequent presence of sewage contamination in the waters where they are bred, thereby causing veritable epidemics of typhoid fever. Just as in fish foods, oysters and mussels, sausages in the meat foods are the most frequent cause of poisoning when they are not quite fresh and thoroughly sound, and from such a cause epidemics from poisoning are frequent in Germany. Sausages are a very nutritious food, as they contain a large amount of fat; their greater value when made from the blood of pigs, on account of its richness in iron, will be specially dealt with in another chapter.

Fish contain somewhat less albumin and much more water than meat, but some of them are rich in fat, such as the eel. We show in the following table the nutritive values in each 100 parts of some of the most frequently eaten fish:—

Fish contain as a rule very little extractive substances compared with meat, and are therefore less tasteful; but still the fatter fish have an agreeable flavor, and are pleasant to the taste. As a general rule, they are more digestible than meat, and also have less of other disadvantages than meat food, on which we will dwell more fully in another chapter.

On the other hand, it is more important than with meat that fish should be absolutely fresh, which would be best attained by keeping them alive in water until just before being required for the table. Boiled fish is the most digestible, fried less so, and pickled or smoked the least.

The most perfect animal food is milk, as it contains all the three principal elements of nourishment, and in normal digestive organs is easily resorbed. As in the case of meat diet, we will deal more fully with this most important and wholesome food in a special chapter. We will content ourselves with mentioning here that milk not only contains the three principal elements of food, but also most of the equally important organic and inorganic minerals, without which life would be impossible. It contains very important organic phosphorized combinations in the shape of lecithin and nuclein; and of the inorganic salts, lime exists in milk in a much greater degree than in any other food. Besides the albumin, carbohydrates, and fat which it contains, milk comes under the category of foods which are richest in mineral salts, especially lime, of which cows’ milk contains 1510 milligrammes in every 100 grammes of desiccated substance, according to Bunge. In iron only is cows’ milk very poor, and therefore when milk forms the main part of our daily nourishment it will be necessary to partake of iron at the same time, which we can best do by eating sausage and puddings made from pigs’ blood (see Chapter XXXVIII).

According to Professor Rubner milk and the various products of milk contain the three main elements of food, in each 100 parts, as follows:—

According to Bunge the following is the composition of cows’ milk, human milk, and the milk of some animals which rank nearest to human milk; each 100 parts contain:—

The milks nearest to human milk in composition are those of the horse, ass, and goat. It is a very interesting fact that goats’ milk contains ten times as much iron and nearly seven times as much lime as human milk, and also ten times as much iron and eight times as much lime as cows’ milk. On account of its nearer similitude to human milk than the cows’ milk, and also because of its being richer in valuable minerals, we will later on, in the chapter on the advantages of milk food, advocate its use in preference to cows’ milk. We will also show at the same time that milk must not be boiled, for by so doing very valuable ferments contained in the milk will be destroyed. Woman’s milk is richer in these ferments. According to Beauchamp, Bouchut, and Moro, there is a diastatic ferment in breast milk, but not in cows’ milk. Manfur and Gillet found a saponifying ferment in mothers’ milk which is less active in that of cows. Luzatti and Bianchini found a starch-separating ferment in woman’s milk which is absent in cows’ and goats’ milk. According to Spolverini, cows’ milk has the same ferments as has human milk, except the amylolytic ferment, and also a salol splitting element that has been discovered by Nobecourt and Merklen in the milk of woman.

Butter is a milk product in daily use, and is one of the foods most used in our diet; and as it is consumed in connection with carbohydrates, we will refer to it later, when discussing the question of carbohydrates generally; but we may mention here that butter must be taken only in a fresh condition, and it should not contain a greater proportion of salt than 2.5 grains per ounce, for reasons we have so often insisted upon in our general remarks on food when referring to common salt, and also in the chapter on the hygiene of the kidneys. When butter is in a rancid condition it produces acid fermentation in the stomach, and also disorders of the intestinal functions.

Cheese is a milk product very rich in fat, consisting of the coagulated casein of the milk fats and salts. American, Canadian, and English cheese are manufactured from pure milk, while the majority of cheeses of other manufacture are made from skimmed milk. A very nutritive cheese is made in Norway from the pure milk of goats; this has a very pleasant taste and is very easy to digest. By moderately pressing fresh curds cream cheese is made; and we are of the opinion that in this form it is more hygienic than old cheese, and we therefore give the preference to cream cheese, or to cheese made from pure milk that is not old or sour. Cheese is a very valuable article of nourishment on account of the large amount of albumin and fat that it contains. Gervais and other sorts of cream cheese have a very high percentage of fat.

Dr. Haig^[264] recommends cheese as a valuable article of food in the dietetic treatment of uric acid diathesis. It has also the great advantage of being able to check intestinal putrefaction, owing to its milk and fatty acid contents.

On the other hand, sometimes very old cheese may cause intestinal putrefaction, with symptoms of intoxication, and serious catarrh of the intestines. Professor Vaughan, of Ann Arbor, found toxic ptomaine bodies in cheese and old and stale milk.

Many people are unable to digest cheese well; others develop skin eruptions or acne after eating it; but, for those who can take it, it is very valuable as an article of diet when a lacto-vegetarian regimen is followed, as suggested in our general remarks on diet.

In addition to milk and meat, the next most important animal food is eggs, which are very rich in a most soluble animal albumin, and also in a substance which plays an important part in the structure of the nervous system—lecithin. According to König^[265] chicken’s eggs have, in their natural watery condition, 13 per cent. of albumin and 0.3 per cent. of fat; and 89 per cent. of albumin and 2 per cent. of fat in the dried substance of the white part; whereas the yolk, in the natural watery state, contains 16 per cent. of albumin and 32 per cent. of fat, while, if dried, 33 per cent. of albumin and 65 per cent. of fat. Eggs also contain much lime.

Eggs with milk, carbohydrates, and fat together constitute a food which, in our opinion, is the most perfect, and one which will enable us to live a longer life in perfect health, even with a complete exclusion of meat; though if we take in addition a little of this latter at dinner we may increase considerably in weight, notwithstanding bodily exercise, as the author found from personal experience and from observations on a series of patients. Therefore, we again repeat that the above appears to be the most beneficial diet to follow if we wish to obey the dictates of health and enjoy a prosperous long life.