Protein digestibility is decreased by cooking, except in the case of egg whites. If egg white is just curdled it is rendered more easily digestible--if it is boiled hard it is made difficult of digestion. Meat protein is hardened at 160° F. Meat is more easily digested raw than cooked. Milk protein is coagulated at 145° F. and becomes less digestible than raw milk.

Sensitive amines are supposed by some to be saponified by heat, especially in the presence of water. Becoming a bit technical, for which I apologize to my lay readers, the amine group is replaced by the hydroxyl group in the foodstuffs and it has been shown that the hydroxides cannot be reaminised by the animal body. This means that the protein has been reduced to useless substances. It is said that while among the synthetic amines there are many which, owing to peculiar structural conditions, the amine group is readily detachable, no such substances are known among the natural amines. This is not wholly true, for it is known that water in which meat has been boiled contains more ammonia than was demonstrable in the meat. There is unquestionably a splitting off of certain amines. To assume that this has no bearing on nutrition in the absence of direct proof of such effect does not seem to me to be justifiable.

When either cystin or cystein are heated in the presence of water the sulphur is split off so that, as Berg says: "both cystin and cystein are * * * rendered valueless for nutritive purposes, inasmuch as sulphydration cannot be affected in the animal body." He says that this decomposition of the sulphhydril group of amino acids by heat in the presence of water "does actually occur."

I quote the following from Vitamins by Ragnar Berg: "the experiments of Francis and Trowbridge and those of Trowbridge and Stanley have shown that when meat is boiled even for a comparatively brief period, organic phosphates are transformed into inorganic."

Berg says: "Besides the sulphur group, we have reason to suppose that the food contains other groups of substances with a readily modifiable composition. * * * We are, however, certain that the proteins, and especially the neucleoproteins, contain thermoliable mixed-organic compounds." He mentions certain phosphates that are rapidly transformed by the cooking process and points out that while the body is capable of taking the more complex phosphates and reducing them to lower stages, it is unable to reverse the process. Only plants can do this.

Simple prolonged heating of foodstuffs, especially at high temperatures or under pressure, produces the following effects:

1. The disaminisation (deaminization) of vitally important amine compounds.
2. The decomposition of similar sulphur compounds (and perhaps of substances belonging to other unstable groups.)
3. The metamorphosis of metaphosphates and pyrophosphates into orthophosphates.

The first two of the above listed effects renders it impossible for the foodstuffs to be assimilated to form cell-substance, for the unstable groups in the food mixture will have been destroyed.

In considering the evils that may flow from deaminization of proteins (or of amino acids) by the cooking process, it is probably important that we think primarily of the effects of cooking upon the essential amino acids. Berg's conclusion, however, after reviewing the evidence, is that deaminization is not as important as the change of organic phosphates into inorganic.

Prof. Charles Richet, of the Paris Academy of Sciences, fed raw beef juice to tubercular patients and reported excellent results from this diet. He concluded however, that cooking meat interferes with the perfect assimilation of it that might otherwise occur. Rare beef has no vitamin value and its iron is said to be very poorly utilized by the body. This is probably not so of the iron in raw beef.

The British sociologist, Anthony Ludovici, recounts an instructive experience with cats. He bred cats for the purpose of studying the process of birth. He discovered that cats actually enjoy the process of birth, that they purr while their kittens are being born. Mr. Ludovici realizing that animals never cook their foods, took it for granted that his cats should have raw meat. Then, on one occasion, he was called away to the country and left one of his female cats in the care of some friends. When her kittens were born shortly after his return, her flanks heaved helplessly for several hours and she groaned almost like a human being. He despaired of her ever delivering her kittens. Inquiry revealed that his friend had fed the cat on cooked meat, vegetables, bread and milk and milk puddings. Further investigation revealed that not merely the happiness of cats during parturition but of other animals also, is inseparably connected with optimum condition during gestation--pregnancy. He found he was able to produce pleasurable or painful parturition at will by feeding his cats in different manners and keeping them indoors or outdoors. He discovered that he could do the same thing with bitches and, upon inquiry among shepherds, discovered the same thing among sheep. He tells of difficulties among cows and horses fed in certain very unwholesome ways. I have never seen difficulty in cows, and I have watched the birth of many calves, but these cows were supplied with good pasturage and were outdoors all through gestation. Not merely raw flesh foods, but uncooked foods of all kinds, are best for food.

In Vol. 39 (pages 21-31), 1939 of the Transactions of the American Therapeutic Society, F. M. Pottenger, M. D., and D. G. Simonsen recount the results of some experiments which they performed with cats. For a lengthy period of time they fed two groups of cats on similar quantities of meats and vegetables. The only difference between the diets of the two groups was that the meat of one group was uncooked, that of the other group cooked.

These men report that all the cats that received the uncooked flesh led normal lives, appeared perfectly healthy and were able to reproduce themselves throughout the length of the experiment which ran through several generations. On the other hand, none of the cats fed cooked meat were able to maintain good health for any length of time, nor were some of the second and third generations able to reproduce. All of the cats eating cooked flesh developed very serious troubles, such as softening of the bones, including those of the skull, bowed legs, rickets, curvature of the spine, paralysis of the legs, thyroid abscesses, convulsions, cyanosis of the liver and kidneys, enlarged colon, degeneration of the motor nerve ganglion cells throughout the spinal cord and brain stem, with some cells affected in the cerebellum and cerebral cortex.

The reader's attention is directed to the cumulative effects of this diet. A diet that seems adequate in one generation may turn out to be very inadequate if carried out through a few generations. It should not be thought that because a particular mode of eating seems adequate for an individual that it will not produce serious results in the children or grandchildren. Long ago it was said: "The fathers have eaten sour grapes and the children's teeth are set on edge."