Probably, one of the chief reasons why persistent efforts were made to improve the dietary of the navy was the prevalence among the men of the disease known as beriberi. "While no satisfactory explanation as to the cause of the disease was offered, it was generally believed that there was some very close relation between the disease and the rice diet" (Oshima). During the years 1878-1883 inclusive, nearly 33 per cent of the marines suffered from beriberi. With the adoption of the new ration in 1884, in which a large part of the rice was replaced by bread and other articles, and with better hygienic conditions, this disease immediately began to disappear, and during the six years after the adoption of the new diet only 16 per cent of the marines were affected by the disease. Later on, hardly more than two or three cases a year were recorded. Advocates of a high proteid diet bring forward this illustration as an evidence of the danger connected with a lowered proteid intake; i.e., that the nutrition of the body will be impaired and diseases of various sorts liable to follow. Yet, Oshima is very careful to state, " It should be especially noted that here no attempt has been made to indicate the cause of beriberi or the relation between the diease and the diet. That rice in itself can be a cause of the disease is not to be considered for a moment. Further, so far as any facts are concerned", the writer can see no ground for considering that a low rate of proteid metabolism has in itself any direct connection with the disease. From a dietary standpoint, it seems far more plausible to assume that the great restriction in variety of foods, so strikingly manifest in the dietary of the poorer people of Japan, results in a lack of some one or more elements which conduces to the disease, just as in scurvy the lack of fresh vegetables on long voyages was liable to be followed by an epidemic of this disease.

Consider the natural character of the dietary of the great bulk of the Japanese people, determined as it was by adverse financial circumstances. As Oshima states, "The rural population of the interior depends very largely or entirely upon a vegetable diet. Fish is eaten perhaps once or twice a month, and meat once or twice a year, if at all. The poorer working classes in the cities also use very little animal food. But the poorer classes in the city and the peasantry of the rural districts comprise nearly 75 per cent of the total population, and it is therefore safe to assume that this proportion lives chiefly, or wholly, upon vegetable diet. And this, it may be observed, means vegetarianism literally. The so-called lacto-vegetarianismis unknown in Japan. Cows are scarce, and milk and other dairy products are expensive, and such as are available are consumed almost entirely by the wealthier people in the cities." It is also to be noted that the amount of fat in Japanese dietaries is very small The reported data indicate that the usual vegetable dietaries contain only about 10 grams of fat per day, while even in the average mixed dietaries the amount rarely rises above 20 grams per day. In other words, the ordinary food of the Japanese was characterized by great lack of variety, and with such a preponderance of carbohydrate materials of a limited kind that it is easy to conceive of a possible dearth of some essential or accessory element, necessary for the preservation of that nutritive balance which aids in protection against disease.

If the resistance of the body to disease germs and toxic influences in general is really diminished by reducing the consumption of proteid food below the set dietary standards, then obviously here lies a tangible reason for the maintenance of a high proteid intake. I know of only one series of scientific observations that bears directly on this question. Dr. Reid Hunt of Washington has studied recently the power of resistance to the poison acetonitrile of animals kept for some time upon a reduced proteid diet. "My experiments," says Dr. Hunt, "showed in all cases that the resistance was ranch increased." In other words, the animals that had been fed a low proteid ration were able to endure a much larger dose of the poison than corresponding animals on their customary diet; "they resisted 2-3 times the ordinary fatal dose of acetonitrile." This general subject, however, is obviously a very important one, and merits further experimental study under a diversity of conditions.

In conclusion, the facts here presented bearing on food requirements, especially those that relate to the need for proteid food, are seemingly harmonious in indicating that the physiological necessities of the body are fully met by a much more temperate use of food than is commonly practised. Dietary standards based on the habits and usages of prosperous communities are not in accord with the data furnished by exact physiological experimentation. Nitrogen equilibrium can be maintained on quantities of proteid food fully fifty per cent less than the every-day habits of mankind imply to be necessary, and this without increasing unduly the consumption of non-nitrogenous food. A daily metabolism of proteid matter equal to an exchange of 0.10-0.12 gram of nitrogen per kilo-gram of body-weight is quite adequate for physiological needs, provided a sufficient amount of non-nitrogenous foods - fata and carbohydrates - is taken to meet the energy requirements of the body.

The long-continued experiments on many individuals, representing different types and degrees of activity, all agree in indicating that equilibrium can be maintained indefinitely on these smaller quantities of food, and that health and strength can be equally well preserved, to say nothing of possible improvement. The lifelong experience of individuals and of communities affords sufficient corroborative evidence that there is perfect safety in a closer adherence to physiological needs in the nutrition of the body, and that these needs, so far as proteid food is concerned, are in harmony with the theory of an endogenous metabolism, or true tissue metabolism, in which the necessary proteid exchange is exceedingly limited in quantity. There are many suggestions of improvement in bodily health, of greater efficiency in working power, and of greater freedom from disease, in a system of dietetics which aims to meet the physiological needs of the body without undue waste of energy and unnecessary drain upon the functions of digestion, absorption, excretion, and metabolism in general; a system which recognizes that the smooth running of man's bodily machinery calls for the exercise of reason and intelligence, and is not to be intrusted solely to the dictates of blind instinct or to the leadings of a capricious appetite.