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Randomized Trial Comparing Consumption of Military Rations to Usual Intake for 21 Consecutive Days: Nutrient Adequacy and Indicators of Health Status

Published:August 19, 2020DOI:



      The US military Meal, Ready-to-Eat food ration is approved as a nutritionally adequate sole source of nutrition for ≤21 days. However, the ration continuously evolves, requiring periodic reassessment of its influence on nutritional status and health.


      To determine the effects of consuming the US Armed Services Meal, Ready-to-Eat ration for 21 days, relative to usual diets, on nutrient intake, and indicators of nutritional status and cardiometabolic health.


      Parallel-arm, randomized, controlled trial, secondary analysis.


      Sixty healthy, weight stable, free-living adults from the Natick, MA, area participated between June 2015 and March 2017.


      Participants were randomized to consume their usual diet for 31days (CON), or a strictly controlled Meal, Ready-to-Eat-only diet for 21 days followed by their usual diet for 10 days (MRE).

      Main outcome measures

      Nutrient intake (absolute and adjusted) throughout the study period, and indicators of nutrition status (vitamins B, D, folate, homocysteine, iron, magnesium, and zinc) and cardiometabolic health (glucose, insulin, and blood lipid levels) before (Day 0), during (Day 10 through Day 21), and after (Day 31) the intervention period.

      Statistical analysis performed

      Between-group differences over time were assessed using marginal models. Models for nutritional status and cardiometabolic health indicators were adjusted for age, initial body mass index, and baseline value of the dependent variable.


      Energy-adjusted fiber; polyunsaturated fatty acids; vitamins A, thiamin, riboflavin, B-6, C, D, and E; and magnesium and zinc intakes all increased in MRE during the intervention and were higher compared with CON (P<0.05), whereas relative protein intake decreased and was lower (P<0.05). Serum triglyceride concentrations averaged 19% (95% CI 0% to 41%) higher in MRE relative to CON during Days 10 to 31 (P=0.05). No statistically significant effects of diet on any other nutritional status or cardiometabolic health indicators were observed.


      Findings demonstrate that a Meal, Ready-to-Eat ration diet can provide a more micronutrient-dense diet than usual dietary intake aiding in maintenance of nutritional status over 21 days.


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        • Nguyen T.
        2018 U.S. MRE procurement.
        in: Smith J. McClung H. Defense Logisitics Agency; Troop Support. 2019
        • Barrett A.
        • Cardell A.
        Military Food Engineering and Ration Technology.
        DEStech Publications, Inc, Lancaster, PA2012
        • US Depts of Army, Navy, Air Force
        Army Regulation 40-25, Nutrition and Menu Standards for Human Performance Optimization.
        Medical Services, Washington, DC2017: 1-25
        • UA Depts of Health and Human Services and Agriculture
        2015-2 020 Dietary Guidelines for Americans 8th edition.
        US Government Printing Office, Washington, DC2015: 1-144
        • US Dept of the Army
        Revision of sole source Meal, Ready-to-Eat Policy - Action Memorandum.
        1995 (Falls Church, VA)
        • Askew E.
        • Munro I.
        • Sharp M.
        • et al.
        Nutritional Status and Physical and Mental Performance of Special Operations Soldiers Consuming the Ration, Lightweight or the Meal, Ready-to-Eat Military Field Ration during a 30-Day Field Training Exercise.
        US Army Research Institute of Environmental Medicine, Natick, MA1987
        • Thomas C.
        • Friedl K.
        • Mays M.
        • et al.
        Nutrient Intakes and Nutritional Status of Soldiers Consuming the Meal, Ready-to-Eat (MRE XII) during a 30-Day Field Training Exercise.
        US Army Research Institute of Environmental Medicine, Natick, MA1995
      1. Combat Rations Database.
        • Karl J.
        • Armstrong N.
        • McClung H.
        • et al.
        A diet of U.S. military food rations alters gut microbiota composition and does not increase intestinal permeability.
        J Nutr Biochem. 2019; 72
        • Jula A.
        • Seppanen R.
        • Alancn E.
        Influence of days of the week on reported food, macronutrient and alcohol among an adult population in south western Finland.
        Eur J Clin Nutr. 1999; 53: 808-812
        • Cantwell M.
        • Millen A.
        • Carroll R.
        • et al.
        A debriefing session with a nutritionist can improve dietary assessement using food diaries.
        J Nutr. 2006; 136: 440-445
        • McClung H.
        • Sigrist L.
        • Smith T.
        • et al.
        Monitoring energy intake: A hand-held personal digital assistant provides accuracy comparable to written records.
        J Acad Nutr Diet. 2009; 109: 1241-1245
        • Craig C.
        • Marshall A.
        • Sjöström M.
        • et al.
        International physical activity questionnaire: 12-country reliability and validity.
        Med Sci Sports Exerc. 2003; 35: 1381-1395
        • Harris J.
        • Benedict F.
        A Biometric Study of Basal Metabolism in Man.
        Carnegie Institution, Washington, DC1919
        • Douglas C.
        • Lawrence J.
        • Bush N.
        • Oster R.
        • Gower B.
        • Darnell B.
        Ability of Harris Benedict formula to predict energy requirements differs with weight history and ethnicity.
        Nutr Res. 2007; 27: 194-199
      2. Food Processor [computer program]. Version 11.0. ESHA, Salem, OR2015
        • Archer E.
        • Marlow M.
        • Lavie C.
        Controversy and debate: Memory-Based Methods Paper 1: The fatal flaws of food frequency questionnaires and other memory-based dietary assessment methods.
        J Clin Epidemiol. 2018; 104: 113-124
        • Schoeller D.
        • Thomas D.
        • Archer E.
        • et al.
        Self-report-based estimates of energy intake offer an inadequate basis for scientific conclusions.
        Am J Clin Nutr. 2013; 97: 1413-1415
      3. Official Methods of Analysis of AOAC International. 21st ed. AOAC International, Rockville, MD2014
        • US Dept of Army, Navy, Air Force
        Nutritional Standards and Education.
        Medical Services, Washington, DC2001: 1-22
        • Gaffney-Stomberg E.
        • Lutz L.
        • Shcherbina A.
        • et al.
        Association between single gene polymorphisms and bone biomarkers and response to calcium and vitamin D supplementation in young adults undergoing military training.
        J Bone Miner Res. 2017; 32: 498-507
        • Hughes J.
        • Foulis S.
        • Taylor K.
        • et al.
        A prospective field study of U.S. Army trainees to identify the physiological bases and key factors influencing musculoskeletal injuries: A study protocol.
        BMC Musculoskelet Disord. 2019; 20: 282
        • Karl J.
        • Lieberman H.
        • Cable S.
        • Williams K.
        • Young A.
        • McClung J.
        Randomized, double-blind, placebo-controlled trial of an iron-fortified food product in female soldiers during military training: Relations between iron status, serum hepcidin, and inflammation.
        Am J Clin Nutr. 2010; 92: 93-100
        • McClung J.
        • Karl J.
        • Cable S.
        • et al.
        Randomized, double-blind, placebo-controlled trial of iron supplementation in female soldiers during military training: Effects on iron status, physical performance and mood.
        Am J Clin Nutr. 2009; 90: 124-131
        • Institute of Medicine, Food and Nutrition Board
        Dietary Reference Intakes for Calcium and Vitamin D.
        National Academies Press, Washington, DC2011
      4. SPSS Statistics for Windows [computer program]. Version 24.0. IBM Corp, Armonk, NY2016
        • Oberleas D.
        • Harland B.
        • Bobilya D.
        Minerals: Nutrition and Metabolism.
        Vantage Press, New York, NY1999
        • Baker-Fulco C.
        Overview of dietary intakes during military exercises.
        in: Marriott B. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. National Academies Press, Washington, DC1995: 121-149
        • Tharion W.
        • Lieberman H.
        • Montain S.
        • et al.
        Energy requirements of military personnel.
        Appetite. 2005; 44: 47-65
        • Murphy N.
        • Carrigan C.
        • Karl J.
        • Pasiakos S.
        • Margolis L.
        Threshold of energy deficit and lower-body performance declines in military personnel: A meta-regression.
        Sports Med. 2018; 48: 2169-2178
        • Burke L.
        • Hawley J.
        • Wong S.
        • Jeukendrup A.
        Carbohydrates for training and competition.
        J Sports Sci. 2011; 29: S17-S27
        • Thomas D.
        • Erdman K.
        • Burke L.
        Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and athletic performance.
        J Acad Nutr Diet. 2016; 116: 501-528
        • Institute of Medicine, Food and Nutrition Board
        Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids.
        National Academies Press, Washington, DC2005
        • Minihane A.
        • Vinoy S.
        • Russell W.
        • et al.
        Low-grade inflammation, diet composition and health: Current research evidence and its translation.
        Br J Nutr. 2015; 114: 999-1012
        • Culling K.
        • Neil H.
        • Gilbert M.
        • Frayn K.
        Effects of short-term low- and high-carbohydrate diets on postprandial metabolism in non-diabetic and diabetic subjects.
        Nutr Metab Cardiovasc Dis. 2009; 19: 345-351
        • Mensink R.
        Effects of Saturated Fatty Acids on Serum Lipids and Lipoproteins: A Systematic Review and Regression Analysis.
        World Heatlh Organization, Geneva, Switzerland2016: 63


      H. L. McClung is a nutritional physiologist, US Army Research Institute of Environmental Medicine, Natick, MA.


      N. J. Armstrong is a research dietitian, US Army Research Institute of Environmental Medicine, Natick, MA.


      J. S. Staab is a research physiologist, US Army Research Institute of Environmental Medicine, Natick, MA.


      S. J. Montain is a research physiologist and division chief, US Army Research Institute of Environmental Medicine, Natick, MA.


      J. P. Karl is a nutritional scientist, US Army Research Institute of Environmental Medicine, Natick, MA.


      S. R. Hennigar is an assistant professor Department of Nutrition, Food, and Exercise Sciences, Florida State University, Tallahassee, FL; at the time of the study, he was a postdoctoral researcher, Oak Ridge Institute for Science and Education (ORISE), Belcamp, MD, for US Army Research Institute of Environmental Medicine, Natick, MA.