organ
less capable of its regular work. And if, again, the food is drenched in
fat, if everything is fried, or if butter is used in large quantities,
the liver becomes overworked and cannot keep up with the demands, and
digestive troubles follow.

_Effect of individual habits._

Assuming that the amount and quality of food have been properly
adjusted, that each of the several constituents is in proper proportion,
and that a suitable variety is maintained, there are still other phases
to be considered before the nourishment of the individual may be
considered satisfactory. Nature has furnished man with a guide both to
the quantity and quality of food that should be taken into the
system,--that is, his desire for food, or his appetite,--and, in
general, this guide may be safely trusted both as to the quantity and
quality, although, in the latter, the appetite is not so trustworthy as
that of the lower animals.

Unfortunately, the appetite is easily distracted by the general
conditions of health, and when once the healthy tone of the system has
been relaxed, the appetite becomes misleading. For instance, a person
not indulging in muscular exercise, but sitting still all day and eating
candy or other sweets, has no desire for food, and the lack of appetite
in this case indicates, not a failure of the need of food, but abnormal
conditions of the system. Also the conditions of housing, lack of
ventilation, excessive heat, excess in the use of stimulants or of food,
all affect and interfere with the guidance of a normal appetite. Some
persons go to the other extreme, and, having been in their earlier years
accustomed to heavy exercise and generous feeding, forget that in a more
quiet life, less breaking down of the tissue occurs and therefore less
food is required. Their appetite is a poor guide since it leads them to
immoderate eating, resulting in time in an overloading of the organs and
the probable poisoning of the system.

_Cooking._

Good cooking is as important as any other part of the process of
digestion, and, in fact, cooking may be said to be the first step, since
there the breaking down of the food tissue occurs, whereby subsequent
action by the juices of the body is made easier. For instance, beef may
be cooked so long and in such a way as to dry and harden the fibers,
making it almost impossible for subsequent digestion; and on the other
hand, it is possible to so stew or boil or steam tough meat as to make