Dietary Intakes From Ad Libitum Consumption of Canadian Armed Forces Field Rations Compared With Usual Home Dietary Intakes and Military Dietary Reference Intakes

Introduction Diet has an impact on weight status, health, and physical performance. Assessing the usual at-home dietary intakes of military personnel can help ascertain their nutritional status before field training or operations. Preference for foods consumed on a routine basis can also impact the military's preference for and consumption of field rations. Military personnel are limited by the inherent nature of the field rations and availability of calories and food types; and despite previous studies indicating a high acceptability of the field rations, it is unknown whether military personnel self-select the same number of calories when faced with a restricted list of field ration options as they would from their usual foods. Although field rations are intended to be nutritionally sufficient for standard military operations, there are limited data on the ad libitum intake of nutrients of Canadian Armed Forces (CAF) personnel from field rations in comparison to the military dietary reference intake (MDRI) recommendations, which establishes standards intended to meet the nutritional requirements of military personnel on duty. Thus, assessing the adequacy of their usual diets at home and longer-term sustenance on field rations in relation to MDRIs can provide insight on CAF personnel's operational readiness. The objectives of this study were to describe and compare, in a convenience sample of CAF, their ad libitum nutrient intakes from the consumption of self-selected field rations at home with their usual home intakes and to compare both with MDRI recommendations. Materials and Methods Eighteen CAF participants weighed and recorded their dietary intake from the ad libitum consumption of field rations at home and their usual at-home diets. Both MDRIs and the Institute of Medicine's dietary reference intake recommendations were used to assess the adequacy of intakes for each individual. Paired Student's t-test or Wilcoxon-matched paired tests were used to compare nutrient intake levels between usual at-home diets and field rations consumed at home. Results Mean daily energy intakes were similar between ad libitum intakes from field rations (2,688 +/- 619 kcal) and usual home diets (2,657 +/- 580 kcal), although participants had significantly higher intakes of protein and fat from their home diets and higher intakes of carbohydrates from the field rations (P <= 0.05). Participants had less than the recommended intakes of some micronutrients (vitamins A and D, folate, calcium, magnesium, and potassium), from both their home diets and field rations, but adequate intakes of vitamin C and iron. Conclusions The results of this study showed no difference in energy intake between the consumption of field rations and home diets, with levels consistent with recommendations for individuals with average physical activity levels. The results also demonstrated less than the recommended intakes (in comparison with MDRIs) of some nutrients from both home diets and self-selected consumption of field rations, warranting further research into nutritional adequacy for operational readiness.