really required is that which will keep up normal strength, normal
circulation, normal colour, normal temperature and normal mental
power. As we have got perfectly definite standards of all these normal
conditions, serious danger can only be run into by neglecting to
measure them.

It is also possible to tell fairly accurately the quantity of food a
man is taking in a day, and then, by collecting and estimating his
excreta, the quantity also out of this food which he is utilising
completely and burning up in his body.

You would say that no danger should be possible with all these
safeguards, and yet the above case history shows that of two trained
physiologists, members of the medical profession, one died at least
twenty years before his time, and the other was in great danger and
only recovered slowly and with difficulty. Another similar case came
to the writer suffering from increasing debility and what appeared to
be some form of dyspepsia. He was quite unable to pass any of the
above-named tests as to physiological standards, and an investigation
of his excreta showed that his food was at least one-fifth or
one-sixth below its proper quantity and had probably been so for many
months past. Some of his doctors had been giving his "disease" a more
or less long list of names and yet had not noted the one essential
fact of chronic defective nutrition and its cause--underfeeding.
Naturally their treatment was of no avail, but when he had been sent
to a nursing home and had put back the 20 lbs. of weight he had lost
he came slowly back to more normal standards and is now out of danger.
In this case there was marked loss of weight, and few people, one
would think, would overlook such a sign of under nutrition. But loss
of weight is not always present in these cases, at least not at first.