Not Eating Enough: Overcoming Underconsumption of Military Operational Rations (1995)

PART I OUTLINES THE TASK presented to the Committee on Military Nutrition Research (CMNR) by scientists at the U.S. Army Research Institute of Environmental Medicine (USARIEM) and the U.S. Army Natick Research, Development and Engineering Center (NRDEC): to evaluate the data on and problem of underconsumption of military operational rations and recommend strategies for overcoming this underconsumption. As part of the charge to the CMNR, the Army posed the following five questions:

1. Why do soldiers underconsume (not meet energy expenditure needs) in field operations?

2. What factors influence underconsumption in field operations? Identify the relative importance of rations, environment, the eating situation, and the individual.

3. At what level of consumption is there a negative impact on physical or cognitive performance?

4. Given the environment of military operations, what steps are suggested to enhance ration consumption? To overcome deficits in food intake? To overcome any degradation in physical or cognitive performance?

5. What further research needs to be done in these areas?

In Chapter 1, the committee reviews the data on deficits in energy intake and its relation to reductions in soldiers' physical and cognitive performance by using relevant background materials, data from controlled field studies, and

the workshop proceedings from November 3–4, 1993. The committee begins by defining the terms used in the report and proceeds with a review of factors that lead to reduced energy intake, the potential effect on performance, and possible solutions to overcome underconsumption. The committee views underconsumption as a particular problem for rapidly redeployed troops who have lost 5 to 10 percent of their body weight without the opportunity to regain it. For the physically fit soldier with low body fat, less fat loss and more reduction in lean body mass will accompany continued weight loss, thereby increasing the risk for reduced performance capacity.

The CMNR answers the questions posed by the Army in Chapter 2 before presenting their conclusions, recommendations, and suggestions for future research. In concluding that soldiers' energy intakes must match their energy expenditures, the committee acknowledges the multiple logistical, situational, and sensory factors that contribute to underconsumption in field operations. To enhance consumption of military operational rations, the CMNR concludes that steps need to be taken to enhance rations, to make specific time available for eating, and to cope with the factors that detract from ration acceptance. The CMNR recommends the establishment of a field feeding doctrine to parallel the water doctrine that is already in place. In addition to the field feeding doctrine, the CMNR further recommends keeping soldiers well-hydrated to avoid hypohydration-induced anorexia, enhancing the MRE to improve consumption, educating commanders about the relationship between ration intake and performance, introducing snacks to increase energy intake, and developing promotional materials for the information of commanders and soldiers alike. Guidance is also provided regarding the rate of weight loss and the potential for performance decrements.