That this mere clinical observation is not fallacious is also shown by the fact that after eating much meat nervous disorders are far more frequent; and we find many more instances of neurasthenia and hysteria among eaters of much meat than among vegetarians; and in the treatment of many nervous disorders far better results are obtained after excluding meat from the diet. It is noticeable in a marked degree in Graves’s disease, and also in myxœdema, that patients suffering from them will not improve with meat, and after partaking of it their symptoms are aggravated. This is only natural, as these diseases are caused by changes in the thyroid gland, to which we have referred in Chapter II, where we have also shown that this gland undergoes changes through an overabundance of meat. We have there mentioned the very interesting experiments of Leo Breisacher, of Detroit, and of Blum, of Frankfort, and others. But we would wish to remark here that it has been demonstrated by the experiments of Chalmers Watson, of Edinburgh, that when certain animals, such as fowls, eat much meat to the exclusion of all other kinds of food, they present great enlargement of the follicles of the thyroid gland, and that rats, kept on the same diet, exhibit even a degeneration of the gland, which can even go to the extent of presenting the clinical picture of Graves’s disease. Not only the thyroid, but the other ductless glands also, have been found altered after an exclusive meat diet. Forsyth[276] found also an enlargement of the follicles of the pituitary body in birds of prey, and Houssaye[277] found that chickens lost their fertility after such a diet, which affected their ovaries. Footnote 276: Forsyth: Lancet, 1907. Footnote 277: Houssaye: C. R. Académie des Sciences, p. 934, 1903. There are numerous clinical and anatomo-pathological evidences to show that the other ductless glands also—that is, the glands with internal secretion, such as the liver, kidneys, and even also the pancreas—are altered by an abundance of meat food if long continued. We have already dwelt on the fact that the liver has the function of destroying the harmful products that are formed by the decomposition of meat food. Thus the more meat we eat the more work is thrown on the liver, which may first become hyperæmic, but, through the continuation of the harmful agency more deleterious conditions may develop. Every physician can observe daily, as we have, that when patients suffering from disorders of the liver take meat, they gradually get worse, but when they give up meat they soon get better. If, therefore, we desire to retain our vitality for a long time, it is best for us not to take too much meat.