It is true of any people, that those with means live in better houses and have a more varied and abundant food supply than do the less prosperous part of the population. The poorer classes among Orientals, as in Western nations, live, generally speaking, on a simpler diet than the well-to-do. While it is true that simplicity in diet is perfectly safe and satisfactory provided the food is wisely chosen, there is more danger that a food supply which is monotonous and contains but few articles, will be sufficiently poor to make its effects clinically recognizable, than would be the case if the food offered greater variety. This might be true even though the faults in the diet were of the same magnitude as those of the simpler one, for in the former case the frequent changes in menus would cause an alternation of the factors which depart from the normal, whereas in the latter case the same factors would tend to be faulty over a long period and their effects would be cumulative and would accordingly do more damage.

It is for the reason just stated that the poorer classes in several parts of the world suffer from beri-beri. Any people having a relatively high incidence of any deficiency disease, are certainly to be regarded as a group all members of which, so far as they subsist upon a similar type of diet, are borderline cases of malnutrition whether or not they show any clinically recognizable signs of disease. There is good reason to believe that the Japanese people can become larger and more powerful physically if they can institute certain changes in the character of their diet.