With a meat diet, especially when taken in large quantities, it is obvious that a good cleansing of the bowels will be all the more necessary, and this is best obtained by the addition to such a diet of fruit, vegetables, and sour milk. By precautions such as these the harm from a too abundant meat diet may be reduced or at least limited; but for those who are desirous of attaining an advanced old age, the greatest moderation in the matter of meat consumption is strongly recommended. When we study the nature of the diet enjoyed by persons who have lived to and over 100, we find, indeed, exceedingly few who are great meat eaters; very many are persons who eat no meat at all; and in many cases, also, the original meat diet was subsequently abandoned in advanced age. According to the report of the Collective Investigation Committee of the British Medical Association, the 55 centenarians whose cases they examined were, for the most part, small meat eaters.[289] Footnote 289: Quoted after Humphrey. ------------------------------------------------------------------------ CHAPTER XXXIX. ON THE GREAT ADVANTAGES OF MUCH MILK IN THE DIET FOR THE PREVENTION AND TREATMENT OF OLD AGE. WE have often observed that patients taking large quantities of milk daily, together with eggs and vegetables, and little meat, soon begin to look better, and sometimes even younger. We have also observed upon ourselves the great advantage of such a diet in comparison with other diets. It is not surprising that persons using large quantities of milk daily look fresher and younger if we consider that when we take much fresh raw milk we are also taking extracts of various ductless glands, and especially of the thyroid. It has been shown by Bang,[290] Mossé,[291] and others, that the internal secretion of the thyroid passes into the milk. There are, indeed, several facts which prove that thyroid secretion is contained in the milk. As we know, the iodine in our body comes mainly from the thyroid, which, of all organs, is the richest in iodine. Now there can be no doubt that iodine enters the milk, for when we give iodine to the mother it can pass, by way of the milk, into the infant. As the thyroid of the infant, or of puppies, contains very little or no colloid substance, upon which, as shown by R. Hutchison and Oswald, the quantity of iodine depends, they must receive the iodine from the maternal milk. Mario Flamini (Revue mensuelle des maladies de l’enfance, 20, 97-120), by injecting iodipin into a goat, obtained milk containing as much as 0.12 gramme iodine to the liter. Another very important fact is that children suffering from congenital myxœdema never show any symptom of this condition so long as they are taking their mothers’ milk; but as soon as they are weaned symptoms of myxœdema appear, which we must logically ascribe to want of thyroid secretion. Footnote 290: