“Arctic Survival Rations. VI. The Physiological Effects of Restricted Diets During Successive Winter Field Trials”, 1959-08-01 (; similar):
2⁄3 different 1,000 calorie combinations of pemmican and sugar were fed to each of 12 subjects during a two-phase, winter field study. All of the diets tested consisted primarily of pemmican, with the sugar contribution ranging from 0 to not more than 32% of the calories. The 5-day experimental phases were separated by a 7-day “recovery period.”
In both periods, on all diets, performance was considered adequate for survival situations involving moderate activity, thus confirming a previous report. The isocaloric substitution of pemmican with 40 grams of sugar raised the fasting blood sugar levels, decreased the nitrogen balance, and, in some cases, reduced ketonuria. However, a further increase in the proportion of sugar in the ration to 80 grams had no additional effect.
In the second period, the magnitude of all the above responses was strikingly reduced. In most cases, the degree of reduction did not appear to be related to differences in the composition of the Period I diets. The fasting blood sugars during the second period, however, did bear an inverse and highly statistically-significant relationship to the levels of carbohydrate intake during the first period. Thus, the data suggest that the adaptation to caloric restriction which developed during the first period, as evidenced by sequential changes in blood sugar levels, nitrogen balance and ketone body excretion, persisted throughout the recovery period, permitting the subjects to respond more favorably to the second dietary stress.