In contrast to the temperature measurements taken in the mouth, the temperature measurements made in the rectum were of true physiological significance. These were obtained at the end of the night experiments with the respiration chamber in Boston and just before the subject arose in the morning. For this purpose 12 accurate clinical thermometers were used; all of these thermometers had previously been carefully calibrated with a standard Richter thermometer. Owing to the darkness of the chamber it was impossible for the experimenters to insert the thermometer personally. After the bulbs of the thermometers had been coated with vaseline, each man was instructed to insert a thermometer more than half its length in the rectum. Inasmuch as the men were an unusually intelligent group and thoroughly appreciative of the importance of the experiment, we have reason to believe that the thermometers were in all instances satisfactorily inserted and that the temperature recorded may be taken as a true measure of the rectal temperature of these men. After the thermometers had been removed they were carefully read and checked by a second person before the records were finally made.

The special advantages of taking rectal temperatures under these conditions were, first, that the subjects had all received a constant standard meal at 5 p. m. the night before. Furthermore, they were lying on the beds inside the chamber for not less than 7 to 8 hours prior to the temperature record; during this time the environmental temperature was almost absolutely constant, and, except in very rare cases, the subject slept the entire night. Finally, as stated above, the temperatures were taken the first thing in the morning, before activity of any kind was engaged in. The conditions thus seemed to be ideal for obtaining true records of the rectal temperature. As with a number of our observations, the records of the rectal temperature under these conditions were not begun until November 11; hence the rectal temperatures of Squad A prior to diet reduction were not secured.

The rectal temperatures obtained for Squad A throughout the entire series are given in table 21. From this it is seen that the only-record of a really abnormal temperature was that for Kon on December 9. Gar, on November 25, had a slight rise in temperature which, after his return to Springfield, was followed by another rise in temperature due to a cold. The inspection of these figures shows that the temperatures were practically all within so-called "normal" limits. It should be observed, however, that the group averages are not strictly comparable. Thus, on all measurements subsequent to December 9, Spe was missing. On January 13 Tom was likewise missing, and on January 27, owing to the fact that Tom had had an operation for hemorrhoids, the axillary temperature alone could be obtained.

Table 21. - Rectal Temperatures During Period With Reduced Diet1 - Squad A

[Subjects post-absorptive and in lying position].

Subject.

Nov. 11.

Nov. 25.

Dec. 9.

Dec. 20.

Jan. 13.

Jan. 27.

Feb. 3.

oF

°F.

°F.

°F.

°F.

°F.

°F.

Bro........

97.6

97.4

97.2

97.0

96.7

97.1

97.6

Can........

97.7

97.6

97.7

98.2

97.7

97.6

97.8

Kon.......

97.9

97.9

100.2

97.3

97.9

97.7

99.0

Gar........

96.6

99.0

96.3

96.9

96.8

95.8

96.0

Gul........

97.1

96.5

97.7

97.1

97.1

97.0

97.3

Mon.......

98.4

97.8

98.5

98.8

97.7

98.2

98.7

Moy.................

98.0

97.1

97.5

97.4

97.2

96.8

97.1

Pea........

97.5

96.8

97.4

97.2

97.1

97.1

96.6

Pec........

98.1

97.9

98.5

98.0

97.2

97.1

97.2

Spe........

97.4

97.5

97.6

.........

...........

..........

...........

96.8

97.1

97.3

96.7

...........

296.3

97.2

Vea........

98.2

97.5

97.9

98.0

97.6

98.0

97.4

Average....

97.6

97.5

97.8

97.5

97.3

97.2

97.4

1 Observations were made early in the morning after a night in the group respiration chamber.

The last preceding meal was the standard supper (700 cals.) served at the restaurant. 2 Taken in axilla; not included in average.

On the other hand, actual computations show that the changes in temperature of the individuals were so slight that excluding one or two men does not materially alter the general average for the temperature measurement. The average values for the complete series ranged from the maximum of 97.8° F. on December 9 to a minimum of 97.2° F. on January 27.

Under these conditions it is clear that the average rectal temperature of Squad A from November 11 to February 3, inclusive, can not be said to have undergone measurable change. An examination of the data for different individuals shows likewise no tendency for a distinct alteration in temperature, and we must conclude that the effect of the reduced diet upon these men is without influence upon the rectal temperature taken under the conditions observed in these tests.

It would be conceivable that with Squad A a perceptible fall in temperature might take place in the first month of the diet reduction. This of course would not be shown by our values, as we had no records of the normal temperatures previous to the reduction in food. With Squad B, however, a sufficient number of rectal temperatures were recorded prior to the diet reduction to give a suitable base line. The records for Squad B are given in table 22. Here the situation is complicated by the fact that occasionally the individual members of the squad were changed for reasons beyond our control, but this, we believe, has no effect upon the general averages.

Table 22. - Rectal Temperatures Of Squad B.1

[Subjects post-absorptive and in lying position].

Subject.

Normal diet.

Reduced diet.

Nov. 18.

Dec. 16.

Jan. 6.

Jan. 14.

Jan. 20.

Jan. 28.

oF

°F.

°F.

°F.

°F.

°F.

Fis.......

97.2

(2)

96.9

96.7

96.9

96.5

Har......

98.3

97.7

98.7

97.9

97.7

96.9

How......

97.9

97.7

97.6

97.5

97.2

97.3

Ham...

97.4

97.5

97.6

97.4

97.2

96.9

Kim......

(3)

(3)

98.3

96.6

97.1

97.1

Lon...

98.4

98.5

(4)

98.6

97.3

96.6

Sch.......

(5)

(5)

97.2

97.4

97.5

96.6

Liv.......

97.9

97.0

97.9

97.7

97.0

97.1

Sne.......

98.3

97.7

97.0

97.8

97.4

97.1

Tho......

98.4

98.5

98.8

97.9

97.3

96.9

Van......

97.5

97.2

97.0

97.1

96.9

96.2

Wil...

97.3

97.4

97.7

96.7

96.9

96.2

Average ..

97.9

97.7

97.7

97.4

97.2

96.8

1 Observations were made early in the morning after a night in the group respiration chamber. The last preceding meal was the standard supper (700 cals.) served at the restaurant.

2 Leo substituted for Fis. Dec. 16; rectal temperature, 97.6° F.

3 McM substituted for Kim; rectal temperature, Nov. 18, 98.5° F.; Dec. 16, 98.1° F. 4 McM substituted for Lon, Jan. 6; rectal temperature, 98.1° F.

5McD substituted for 8ch; rectal temperature, Nov. 18, 98.2° F.; Dec. 16, 97.5° F.

Prior to the diet reduction the values for Squad B on November 18, December 16, and January 6 show averages of 97.9°, 97.7°, and 97.7° F.' respectively. In other words, the rectal temperature can be said with this squad of 12 men to be constant. Subsequent to the change in diet there is, in rather striking contrast to the values found with Squad A, a distinct tendency for the rectal temperature to fall. Thus, on January 14, approximately one week after the reduced diet began, the average temperature was 97.4° F., at the end of two weeks, 97.2° F., and at the end of three weeks, 96.8° F. It is quite clear from an inspection of the individual values that this is a positive reduction in temperature which was not found with Squad A, although the absence of true normal values for the latter squad complicates the comparison. Furthermore, the absolute minimum value of 96.8° F. on the last day (January 28) is perceptibly lower than the average minimum found with Squad A on February 3, that is, 96.8° F. against 97.4° F. The only explanation that one can offer for this difference is the fact that Squad B, during the month of January, was on an extraordinarily reduced diet, containing but approximately 1,400 net calories, or a little more than one-third of the calories in the maintenance diet previous to restriction.

It is conceivable, therefore, that with so low a diet a slight reduction in temperature may have resulted. This is somewhat in conformity with the experience of this Laboratory with the man undergoing prolonged fasting,1 when it was found that the average rectal temperature throughout the night was somewhat lower at the end of the prolonged fast than at the beginning. This lowering of temperature was likewise observed with this man in the record made at 7 a.m., the temperature being a few tenths of a degree higher at the beginning of the fast than at the end. It would, therefore, appear that with Squad B pronounced undernutrition affected the body temperature slightly, although the fact that so large a reduction in diet (amounting to nearly two-thirds of the previous requirement) had no greater effect upon this important body function is somewhat remarkable. Since the rectal temperatures were so slightly affected, it is not surprising that no appreciable alteration in the mouth temperature could be noted as the experiment progressed.