ter the activity
the higher the increase. Consequently external work calls for food in
addition to that which is used to run the engine, in order to save the
body from destruction.

DuBois[20] finds "Basal Metabolism above normal in exophthalmic
goiter, in fevers, in lymphatic leukemia, and in pernicious anemia,
in severe cardiac disease, and in some cases of severe diabetes and
cancer; it is lower than normal in cretinism, and in myxedema, in old
age, in some wasting diseases and perhaps in some cases of obesity."
This fluctuation in the Basal Rate of metabolism furnishes a factor in
the diagnosis of disease, not only recognized but coming more and more
in use.

FACTORS DETERMINING THE FOOD REQUIREMENTS OF THE BODY

~For the Adult.~--Muscular activity, Age and Size, are most important
factors influencing the food requirements. The physical condition and
environment of the individual also exert a certain amount of influence
upon the intake of food.

~Work.~--Muscular activity, as already stated, increases the body
expenditures; consequently the more active the work the greater amount
of energy food needed per unit of weight.

~Age.~--As the individual grows older, the rate of metabolism
decreases until, in old age, it is not more than a third to a fifth of
what it was in earlier life. This is due to a general "slowing down"
of the machinery, the heart does not beat so rapidly, nor is the
respiration so quick. The digestive organs, the heart, the liver, and
the kidneys, cannot handle the volume of food which was required
during the period of greatest physical activity. Hence, any great
excess over and above that which is needed for the maintenance of the
body in health will be a source of danger to the elderly person. Von
Noorden claims the food requirements of individuals from

60 to 70 years of age to be reduced 10%; for people from
70 to 80 years of age to be reduced 20%; for people from
80 to 90 years of age to be reduced 30%.

~Sex.~--Science has proved, that there is little difference in the
food requirements of men and women, provided they are alike in age,
weight and size, and are doing the same amount and type of work. But
women, as a rule, weigh less than men, hence their food requirements
are approximately less.

Murlin finds the food requirements of pregnant women to be some what
higher than of non-pregnant ones, and the requirements of the nursing
mother to be higher than either (see chapt