Nutrition and Hydration Status of Aircrew Members Consuming The Food Packet, Survival, General Purpose, Improved During A Simulated Survival Scenario

Adequate nutrition and hydration can be crucial to the survival of downed aircrews. To determine the nutritional adequacy and palatability of an improved, all-purpose, all-environment survival packet (GP-I) compared to the old survival packet (GP), a field test was conducted using combat survival school students. During a five day survival exercise, 41 aircrew member's ate the GP-l and 57 ate the GP. Nutrition/hydration status were assessed from food/fluid intake records as well as changes in body weight. Water turnover was measured in a subset of subjects (n=30) using deuterium oxide. Pre- and posttest hemoglobin, hematocrit plasma osmolality, urine specific gravity (SG) and ketones were also measured. Acceptability of the two rations was evaluated. Subjects eating the GP-l consumed more Calories; GP-l 774+/-436 vs GP 642+/-408 kcal/d. Carbohydrate and protein consumption were similar but the GP-l group ate significantly more fat, 35+/-21 vs 24+/-18 g/d. Mean fluid intake was similar for both groups (GP-l 4.3+/-1.7, GP 4.4+/-1.9 L/d). Sodium intakes were 1.6 g/d. Weight decreased significantly for the GP-l and GP groups (2.9+/-1.4, 3.4+/-1.7 kg, respectively); changes were similar between groups. Water turnover data indicated subjects maintained adequate hydration as did hemoglobin, hematocrit, and plasma osmolality. Mean posttest urine SG was 1.024-/+0.007 and moderate amounts of ketones were detected. Both rations received favorable ratings, but the greater variety of the GP-l ration resulted in higher acceptability ratings for this ration. We conclude from these results that either ration is adequate, however, the variety and palatability of the GP-l is more desirable than He GP.