In the same way the kidneys can also be kept in good condition if too much meat be not taken. These eliminate the end-products of meat food, and the more of such products that pass through the kidneys, the more of them are taken from the blood and excreted by means of the fine epithelia of the kidney tubules, and thus the more is the work done by these organs; and we have mentioned that any overwork of an organ may be followed by its exhaustion. As a consequence of eating meat sometimes very harmful products pass through the kidneys, especially in the case of preserved, strongly seasoned, or spiced meat, for such preserved food may contain disease germs, ptomaine bodies, mineral poisons, etc. But even the passage of normal end-products of meaty food—for example, if urea be continually passed for years in large quantities—can produce serious alterations. Many authorities, such as Dr. James Tyson, of Philadelphia, who is well known by his works on the kidneys, attribute to the very frequent taking of such food many cases of interstitial nephritis; and nearly all such authorities, including Senator, of Berlin, prohibit the use of meat in most of the disorders of the kidneys. But we have already referred to the danger of such a diet to the liver and kidneys, and it is only because of the importance of the subject that we have again referred to the matter. There is some clinical evidence in favor of the opinion that the pancreas may also be altered by an abundant meat diet. We know that when this organ is diseased we may discover a quantity of unabsorbed meat fibers in the fæces, indicating that the pancreas has failed to fulfill its task of assisting in the digestion of meat by the production of its ferment—the trypsin. Meat, when taken in large quantities, can thus cause the pancreas considerable overwork, which, in the long run, as is well-known, may cause trouble, as is shown by the fact learned from observation, that diabetes develops generally in meat eaters. Even in dogs an abundant meat diet can produce spontaneous diabetes, a fact we have already published. Diabetes may not only be due to the changes in the pancreas, but also as we have shown[278] to those in the thyroid gland, consequent upon such nourishment. Footnote 278: Lorand: “Die rationelle Behandlung der Zuckerkrankheit,” second edition, Berlin, 1909. It is a very important fact that much meat can become most injurious to diabetic patients, and, as v. Noorden[279] observed, even slight cases of diabetes can be transformed into severe ones in consequence of such a diet; thus, in our opinion, in all severe cases of this disease meat should be prohibited. Footnote 279: v. Noorden: Deutscher Naturforscher Congress, 1902.