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

Chapter: 6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective

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Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

6
Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective

David D. Schnakenberg1

Not Eating Enough, 1995

Pp. 91–107. Washington, D.C.

National Academy Press

Introduction

Nutritional standards for the development and procurement of military rations and Military Recommended Dietary Allowances (MRDAs) (AR 40-25, 1985) for feeding military personnel and assessing the nutritional adequacy of their nutrient intakes have evolved over the past 80 years. These standards and dietary recommendations have been described in various military publications and, beginning during World War II, were prescribed in military regulations. However, specific nutritional criteria for field testing of military rations have emerged from the Office of the Surgeon General (OTSG) of the Army only during the past 10 to 12 years. These criteria were applied during an extensive series of field ration trials that were conducted by the U.S. Army Research Institute of Environmental Medicine (USARIEM) and U.S. Army Natick Research, Development and Engineering Command (USANRDEC) during the same period. The Committee on Military Nutrition Research (CMNR)

1  

David D. Schnakenberg, American Society for Clinical Nutrition, Bethesda, MD 20814-3998

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

participated, in an important advisory capacity to the OTSG, in the recent revisions of the MRDAs and nutritional standards. The CMNR also provided advisory input into the development of the nutritional criteria as well as into the assessment and interpretation of the nutritional data from several of these important field ration trials. Nutritional and other biomedical data were specifically requested and subsequently used by general officers on the Army staff to make decisions during 1986–1988 that improved not only nutritional quality and food consumption, but also troop acceptability of the Meal, Ready-to-Eat (MRE) and Tray rations (T Rations) that were successfully used in military operations during Operation Desert Storm and in Somalia in the early 1990s.

This chapter will briefly review the history of the development of nutritional standards and MRDAs and then, drawing largely on personal experiences while this author was assigned to OTSG and USARIEM, describe the development and application of the nutritional criteria that were used during field testing of military rations during the 1980s and the involvement of the CMNR in those activities.

NUTRITIONAL STANDARDS FOR DEVELOPMENT OF MILITARY RATIONS

L. R. Holbrook, Director of the Training School for Bakers and Cooks, Fort Riley, Kansas, provided the following nutritional guidance in the 1916 edition of The Mess Sergeant's Handbook (Holbrook, 1916, p. 31):

Nothing is of greater importance than that a well-balanced diet be prepared—that is, that a suitable variety of foods appear on the bills of fare, and the various components be served in appropriate quantities.

Few nutritionists or dietitians today would take strong exception to Holbrook's general guidance for feeding soldiers. The nutrition experts developing the next edition of the Department of Health and Human Services-U.S. Department of Agriculture's Dietary Guidelines for Americans may wish to consider adopting John Murlin and Casper Miller's nutritional recommendations for training of soldiers (1919). They recommended a proposed training ration that contained 12.6 percent calories from protein, 30.3 percent calories from fat, and 57.1 percent calories from carbohydrate. The Nutrition Advisory Council to the Army Surgeon General recommended in that same article that the nutrient requirements for training of soldiers was 12.5 percent calories from protein, 25 percent calories from fat, and 62.5 percent calories from carbohydrate.

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

During World War II, the Army Surgeon General was given specific responsibilities for nutrition (U.S. Department of the Army, 1945; U.S. War Department, 1944), including to:

  • determine the nutritional state of military personnel,

  • prescribe basic standards of diet for the Army under various conditions of operations,

  • report nutritional deficiencies and recommend corrective measures,

  • determine nutritional adequacy of menus and rations consumed to ascertain conformance to prescribed nutritional standards, and

  • advise and cooperate with the Quartermaster Corps to secure and maintain nutritional adequacy of the ration.

As noted in an historical account of ration development during World War II (Samuels et al., 1947), a nutritional standard is needed to plan any ration. The standard should be based on requirements adequate for optimal nutrition and not on minimal requirements. Furthermore, nutritional standards should be based on the combined judgments of nutrition authorities and not developed by individual effort. To help establish a satisfactory standard, the Food and Nutrition Board (FNB) of the National Research Council (NRC) was organized in 1940 in conjunction with the defense program. During World War II, the Army Surgeon General's office usually accepted diets as nutritionally adequate if they met the recommended dietary allowances of the FNB published in January 1943 and June 1945 (NRC, 1941, 1945).

After World War II, the term minimum nutrient intake was used for the basic dietary standards for garrison and field rations in the 1947 version of Army Regulation 40-250 (U.S. Department of the Army, 1947). The calorie standard of 3,600 kcal/d in temperate climates was raised to 4,400 kcal/d for extreme cold environments. This regulation was revised again in 1949 (U.S. Department of the Army, 1949) to include standards for female personnel with adjustments for active and sedentary males. The first regulation on nutrition standards representing three branches of the military (Tri-Service Regulation) appeared in 1968 (U.S. Departments of the Army, the Navy, and the Air Force, 1968). Dietary allowances were adopted as nutritional standards based on the 1964 edition of the FNB's Recommended Dietary Allowances (RDAs) (NRC, 1964) with adaptation as required. It was recommended that the desirable proportion of total calorie intake from fat sources was 40 percent or less, and that menus should provide no more than 45 percent of calories from fat sources. The calcium allowance was raised to 1,400 mg for males and 1,300 mg for females. The regulation was revised again in 1969 (U.S. Departments of the Army, the Navy, and the Air Force, 1969) based on the 1968 edition of the RDAs (NRC, 1968). The calcium allowance was lowered to 800 mg, and to reduce risk of heart disease, a reduction of total fat content of the menus to 42 percent of calories, with some substitution of polyunsaturated for saturated

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

fats, was recommended. The regulation was revised again in 1970 (U.S. Departments of the Army, the Navy, and the Air Force, 1970) with added emphasis that fat should not exceed 40 percent of calories in planned menus. T. D. Boaz (1970) from the OTSG explained that the reason for the higher protein allowance for the military is to enable menu planners to provide a diet that is highly acceptable, to incorporate other nutrients with ease, and to provide for the growth needs often found in younger recruits. The regulation was subsequently revised in 1971 and 1972 with no major changes. The 1976 revision (U.S. Departments of the Army, the Navy, and the Air Force, 1976) was based on the 1974 edition of the RDAs (NRC, 1974).

In 1985 the regulation was revised again (U.S. Departments of the Army, the Navy, and the Air Force, 1985) with significant advisory input from the CMNR. The MRDAs were adapted from the 1980 edition of the RDAs (NRC, 1980), and the values for males and females are provided in Table 6-1. A summary of the changes in recommended nutrient allowances from 1943 to 1985 is shown in Table 6-2. The MRDAs were defined as the ''daily essential nutrient intake levels" presently considered to meet the known nutritional needs of practically all 17- to 50-year-old, moderately active military personnel." The MRDAs were intended for use by professional personnel involved in menu planning, dietary evaluation on a population basis, nutrition education, nutrition research, and food research development. The MRDAs were expanded to include safe and adequate adult dietary intake ranges for selected nutrients, known to be essential, but for which recommended levels of intake had not been established. The 1985 edition also explicitly prescribed nutrient standards for operational and restricted rations, and these values are shown in Table 6-3. The intent was for the nutrient standards to be used to evaluate the nutritional adequacy of the ration itself as formulated or as procured, whereas the MRDAs were to be used to evaluate the adequacy of the nutritional intakes of a group of soldiers consuming the ration over a period of several days.

The 1985 edition (AR 40-25, 1985) also recommended that dietary intakes from fat should not exceed 35 percent of total calories for garrison meals, but it allowed up to 40 percent of calories from fat for operational and restricted rations. For the first time, a goal for the sodium content in foods as served in military food service systems was established at 1,700 mg of sodium per 100 kcal. Energy allowances for extreme cold weather operation were adjusted to 4,500 kcal/d for men and 3,500 kcal/d for women.

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

TABLE 6-1 MRDA for Selected Nutrients1

Nutrient

Unit Kcal MJ

Male 3200(2800–3600) 13.4(11.7–15.1)

Female 2400(2000–2800 10.0(8.4–11.7)

Energy2,3

Protein4

gm

100

80

Vitamin A5

mcg RE

1000

800

Vitamin D6,7

mcg

5–10

5–10

Vitamin E8

mg TE

10

8

Ascorbic Acid

mg

60

60

Thiamin (B1)

mg

1.6

1.2

Riboflavin (B2)

mg

1.9

1.4

Niacin9

mg NE

21

16

Vitamin B6

mg

2.2

2.0

Folacin

mcg

400

400

Vitamin B12

mcg

3.0

3.0

Calcium7

mg

800–1200

800–1200

Phosphorus7

mg

800–1200

800–1200

Magnesium7

mg

350–400

300

Iron7

mg

10–18

18

Zinc

mg

15

15

Iodine

mcg

150

150

Sodium

mg

See note10

See note10

1 MRDA for moderately active military personnel, ages 17 to 50 years, are based on the Recommended Dietary Allowances, ninth revised edition, 1980.

2 Energy allowance ranges are estimated to reflect the requirements of 70 percent of the moderately active military population. One megajoule (MJ) equals 239 kcals.

3 Dietary fat calories should not contribute more than 35 percent of total energy intake.

4 Protein allowance is based on an estimated protein requirement of 0.8 gm/kilograms (kg) desirable body weight. Using the reference body weight ranges for males of 60 to 79 kilograms and for females of 46 to 63 kilograms, the protein requirement is approximately 48 to 64 grams for males and 37 to 51 grams for females. These amounts have been approximately doubled to reflect the usual protein consumption levels of Americans and to enhance diet acceptability.

5 One microgram of retinol equivalent (mcg RE) equals 1 microgram of retinol, or 6 micrograms betacarotene, or 5 international units (IU).

6 As cholecalciferol, 10 micrograms of cholecalciferol equals 400 IU of vitamin D.

7 High values reflect greater vitamin D, calcium, phosphorus, magnesium, and iron requirements for 17- to 18-year olds than for older ages.

8 One milligram of alpha-tocopherol equivalent (mg TE) equals 1 milligram d-alpha-tocopherol.

9 One milligram of niacin equivalent (mg NE) equals 1 milligram niacin or 60 milligrams dietary tryptophan.

10 The safe and adequate levels for daily sodium intake of 1100 to 3300 mg published in the RDA are currently impractical and unattainable within military food service systems. However, an average of 1700 milligrams of sodium per 100 kilocalories of food served is the target for military food service systems. This level equates to a daily sodium intake of approximately 5500 milligrams for males and 4100 milligrams for females.

SOURCE: AR 40-25 (1985). U.S. Department of the Army, the Navy and the Air Force.

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

TABLE 6-2 Summary of Changes in Nutritional Standards for the Military (1943–1985)

Reference Nutrition

Standards*

Energy (kcal)

Protein (g)

Fat (% kcal)

Calcium (mg)

Iron (mg)

Vit. A (IU)

Thiamine (mg)

Riboflavin (mg)

Niacin (mg)

Vit C (mg)

FNB RDA‡

1943

3,000

70

800

12

5,000

1.8

2.7

18

75

 

1945

3,000

70

800

12

5,000

1.5

2.0

15

75

AR 40-250§

1947

3,600

100

700

5,000

1.6

2.2

16

50

 

1949

3,600

100

700

5,000

1.6

2.2

16

50

 

 

3,000#

100

700

5,000

1.6

2.2

16

50

Tri-Service Regulation**

1968

3,400

100

<40%

1,400

18

5,000

1.4

2.0

22

60

 

1969

3,400

100

<40%

800

14

5,000

1.7

2.0

22

60

 

1970

3,400

100

<40%

800

14

5,000

1.7

2.0

22

60

 

1976

3,200

100

<40%

800

18

5,000

1.6

2.0

21

60

 

1985

2,800–3,600

100

<35%

800–1,200

10–18

1,000 (µg RE)

1.6

1.9

21

60

 

 

Na (mg/1,000 kcal)

P (mg)

 

Mg (mg)

 

Zn (mg)

I (µg)

Vit. B6 (mg)

Folacin (µg)

Vit. B12 (µg)

 

1985

1,700 "goal"

800–1,200

 

350–400

 

15

150

2.2

400

3.0

* Male personnel; Assumes temperate climate; National Research Council (1941, 1945); § U.S. Department of the Army (1947, 1949); Physically active; # Performing sedentary duties; ** U.S. Departments of the Army, the Navy, and the Air Force (1968, 1969, 1970, 1976, 1985); < 40% intake; < 45% for menus (1968); < 42% for menus (1969); < 40% for menus (1970).77

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

TABLE 6-3 Nutritional Standards for Operational and Restricted Rations

Nutrient

Unit1

Operational rations

Restricted rations2.4

Energy

Kcal

3600

1100–1500

Protein

gm

100

50–70

Carbohydrate

gm

440

100–200

Fat

gm

160(maximum)

50–70

Vitamin A

mcg RE

1000

500

Vitamin D

mcg

10

5

Vitamin E

mg TE

10

5

Ascorbic Acid

mg

60

30

Thiamin

mg

1.8

1.0

Riboflavin

mg

2.2

1.2

Niacin

mg NE

24

13

Vitamin B6

mg

2.2

1.2

Folacin

mcg

400

200

Vitamin B12

mcg

3

1.5

Calcium

mg

800

400

Phosphorus

mg

800

400

Magnesium

mg

800

400

Iron

mg

18

9

Zinc

mg

15

7.5

Sodium

mg

5000–70005

2500–35005

Potassium

mg

1875–5625

950–2800

1 See notes in Table 6-1 for explanation of units.

2 Values are minimum standards at the time of consumption unless shown as a range or a maximum level.

3 The operational ration includes the MCI, MRE, A, B, and T Rations.

4 Restricted rations are for use under certain operational scenarios such as long-range patrol, assault, and reconnaissance when troops are required to subsist for short periods (up to 10 days) on an energy restricted ration.

5 These values do not include salt packets.

SOURCE: AR 40-25 (1985). U.S. Department of the Army, the Navy and the Air Force.

NUTRITIONAL CRITERIA FOR TESTING MILITARY RATIONS

The MRDAs for military personnel and the nutritional standards for operational and restricted rations were the primary references used to develop the nutritional criteria that were used during an extensive series of field ration feeding trials conducted during the 1980s. Examples will be provided from the following four major ration tests:

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×
  • 1983 MRE Test—Hawaii;

  • 1985 CFFS-FDTE Test—Hawaii;

  • 1986 MRE Improvement Test—Hawaii; and

  • 1989 MRE Cold-Weather Supplement Test—Alaska.

Background on Development of the Meal, Ready-to-Eat Ration

The Meal, Combat Individual (MCI) or, more familiarly, the C Ration was a ration packaged in small tin cans and used extensively during the latter part of World War II and during the Korean and Vietnam wars. Beginning in the 1970s, the Army began developing a replacement for the MCI, packaged in a flexible pouch. This ration, which became known as the Meal, Ready-To-Eat (MRE), was not extensively field tested for nutritional adequacy during its development because the emphasis at the time was on changing the packaging, not the food. Difficulties in obtaining approval for the packaging from the U.S. Food and Drug Administration delayed the procurement and delivery of the new MRE until 1983, by which time the existing stocks of C Rations were almost exhausted.

The Office of the Deputy Chief of Staff for Logistics (ODCSLOG) of the Army had initially requested in 1977 that the OTSG conduct a field test to determine whether the new MRE could be used as sole source of subsistence for troops for periods up to 30 days. This question arose because the Headquarters Department of the Army (HQDA) policy at that time, based upon general guidance contained in existing technical manuals and bulletins (U.S. Department of the Army, 1961, 1971, 1974), stated that "the Meal Combat Individual (MCI) ration, although formulated to be nutritionally adequate, should not be used as sole source of food for periods in excess of 10 consecutive days." The rationale given was that the ration will become monotonous, troop acceptance and nutrient intakes will decrease, morale will deteriorate, and as a consequence, troop performance and health may be adversely affected. No one in the OTSG at that time apparently was willing to approve a change in policy for a ration that had not been adequately tested or even produced. Unfortunately, the senior leadership of the U.S. Army Medical Research and Development Command (USAMRDC) at that time was also unwilling to fund and conduct an extensive 30-d field ration trial because they were in the process of disestablishing their existing military nutrition research program at the Letterman Army Institute of Research (LAIR). The Army's nutrition research program at LAIR was eventually transferred, at the direction of Congress, to the U.S. Department of Agriculture in 1979.

1993 MRE Test—Hawaii

The ODCSLOG requested again in 1982 that a 30-d test of the soon-to-be-fielded MRE be conducted, and USANRDEC agreed to conduct the field trial

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

at the Pohakuloa Training Area on the Big Island of Hawaii. Hirsch (see Chapter 9 in this volume) reports the results from the 1983 MRE test. The Commander of USANRDEC asked Major General Garrison Rapmund, Commanding General of USAMRDC, to review and comment on the USANRDEC test plan. As General Rapmund's nutrition staff officer, this author referred the test plan to the CMNR and subsequently incorporated their initial reactions with his own in General Rapmund's response back to USANRDEC. It was agreed that food composition should be measured daily throughout the 6-wk trial and that average daily nutrient intakes should meet the MRDAs. It was also agreed to follow USANRDEC's proposals to measure food acceptance (by hedonic questionnaire), body composition (by anthropometry), hydration status (by urine osmolality), biochemical status (by serum ascorbic acid, serum retinal), and individual morale (by questionnaire) at 2-wk intervals and to measure body weight and screen clinical symptoms by checklist at weekly intervals. These data were to be used to test for differences in responses between a unit of at least 30 soldiers consuming three MREs per day (experimental group) for 6 consecutive weeks compared to a similar unit (control group) consuming two hot, cook-prepared A Ration meals and one MRE per day for 6 weeks. Ideally, there should have been an additional control group fed three MCIs per day so that there would also have been a direct side-by-side comparison of the new (MRE) and old (MCI) ration. However, there were insufficient quantities of the old MCI available for this test.

Although it had been decided that the latest (1976) version of the MRDAs should be used as nutritional criteria for the 1983 MRE test, it was not clear what interpretation should be made if average daily energy intakes fell below the energy MRDA of 3,200 kcal/d. It was agreed that data on body weight change should also be assessed, but there was no existing body weight change criterion established for use in field ration testing. As an interim criterion, this author suggested in General Rapmund's letter to USANRDEC that an average weight loss of less than 5 lb (2.3 kg) could be used to assess how long troops engaged in a 6-wk field exercise will consume sufficient quantities of the test rations to maintain body weight.

After the 1983 MRE test was completed and the initial data were analyzed, USANRDEC forwarded a copy of their preliminary data for review and comment by USAMRDC and the CMNR. The CMNR provided comments in their Letter Report and the following recommendations on what constitutes unacceptable body weight loss (NRC, 1985, p. 2):

Average weight loss of 5 percent during combat or training exercises of approximately one month's duration would be acceptable for healthy fit troops, without significant adverse effects on health or performance. However, body weight loss of 10 percent or more for individuals should be cause for concern. Individual weight loss of 3 percent or more in a one day period due to dehydration would be unacceptable, and could result in excessive losses of physically able troops.

Hirsch (see Chapter 9 in this volume) reports that average daily energy intakes of individuals in a study who ate three MREs per day were far below

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

the 3,200 kcal/d as listed in the MRDAs (AR 40-25, 1985), and intakes continued to decline as the test progressed despite an average body weight loss that exceeded 5 percent. The OTSG reviewed the data and concluded that there was no evidence from this trial to support revision of the existing 10-d restriction on the use of individual rations such as the MRE as the sole source of food.

Background on Development of the Combat Field Feeding System-Force Development Test and Experimentation

The development and eventual fielding of the Combat Field Feeding System-Force Development Test and Experimentation (CFFS-FDTE) resulted in major changes in what and how U.S. military troops are to be fed in combat and during operational training. In the early 1980s, there was a strong movement within the senior leadership of the Army to create a new Light Infantry Division, but Congress would not authorize an increase in the total size of the Army. Under these circumstances, the only option to increase the "tooth" of the Army was to reduce the size of the logistical "tail." One of the general officers in charge of creating the Light Infantry Division learned about a concept briefing being given in the Pentagon by the Quartermaster School that proposed a new feeding system that could greatly reduce the number of cooks needed to serve hot meals to troops on the battlefield. This author attended that briefing, and the General was positively impressed. Shortly thereafter, the General initiated a decision-making process that within about 2 years converted 5,000 cook positions into light infantry soldiers. This decision led to a very accelerated research-and-development cycle to convert a concept solely on paper into a fully developed, tested, and fielded system for feeding the entire Army before the cooks were taken out of the Army inventory.

The new CFFS-FDTE was based on the T Ration. The key new component of the system was a flat, rectangular, half-steam-table-sized metal can (tray pack) that contained 12 to 20 servings of shelf-stable, thermally processed entrees, vegetables, starches, or desserts. Each tray pack could serve as its own heating (in hot water) and serving vessel. The tray packs were configured with bread, beverage mixes, condiments, and disposable dinnerware in 36-meal modules. One of the major challenges to the ration developers was that an industrial base to produce the T Ration menu components with a nonrefrigerated shelf life of at least 3 years had to be developed and tested on an item-by-item basis. This necessity delayed the development of T Ration menus and the nutrient composition data to determine if the CFFS-FDTE ration would meet OTSG's nutritional standards (U.S. Departments of the Army, the Navy, and the Air Force, 1985) for operational rations.

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×
1985 CFFS-FDTE Test—Hawaii

In early 1985, General Maxwell Thurman, the Vice-Chief of Staff of the Army, assembled a room full of general officers and reviewed the status of issues necessary to begin implementing the CFFS-FDTE the following year. General Thurman asked if all the necessary testing had been completed. This author informed him that a field test had not been conducted to determine if troops would eat enough of the ration to meet their nutritional needs. General Thurman then turned to Major General Rapmund and said, "Doc, I want you to ensure this new ration gets adequately tested and fixed, if necessary, to ensure that we will maintain the health and performance of our soldiers when they have to eat this ration for extended periods. We may not have the cooks or the equipment there to serve them a freshly prepared, hot meal."

This tasking from the Vice-Chief of Staff of the Army became the first project for this author as the Director of the newly formed Military Nutrition Division at USARIEM. In conjunction with the U.S. Army Combat Developments Experimentation Center (USACDEC), USARIEM conducted the largest and most extensive field ration trial ever, involving over 1,600 troops from the Twenty-fifth Infantry Division at the Pohakuloa Training Area, Hawaii, during August to September 1985. Six different ration combinations of the T, A, B, and MRE rations were evaluated during the 44-d field trial.

Because this was an Army Operational Test, there was a requirement to define the test objectives, identify the issues, establish criteria, select test procedures, and assign responsibilities to collect, analyze, and evaluate the data in the test plan agreed to by all involved organizations prior to the start of the test. USACDEC was responsible for the operational and organizational plan effectiveness objective and the morale and ration acceptability objective. USARIEM was responsible for the nutritional adequacy and medical evaluation objective. The issues, criteria, and test procedures associated with that objective are briefly summarized in Table 6-4. Note that a separate issue was established to evaluate whether troops would consume sufficient calories to meet the energy demands of the field exercise and that a 3 percent body weight change criterion, with compensation for dehydration, was selected to evaluate this specific issue. The standard values of biochemical indices of acceptable, low, or deficient nutritional status that were used in this test are shown in Table 6-5.

The CMNR was closely involved in an advisory capacity during all phases of this test. Their suggestions were incorporated into the test plan, and a subcommittee of the CMNR (Robert Nesheim, Mark Hegsted, and Susan Berkow) came to the test site and reviewed the data collection procedures. The

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

TABLE 6-4 Nutritional Adequacy and Medical Evaluation—1985 CFFS-FDTE Test

Issue

Criterion

Test Procedure

CFFS-FDTE ration intakes adequate to meet MRDAs?

Average daily energy, protein, fat, vitamin, and mineral intakes of platoon should meet all RDAs.

Food and water intake data measured on 16 days during 44-d test. Nine-point hedonic ratings for each item consumed and reasons for nonconsumption recorded.

Will troops consume sufficient CFFS-FDTE rations to meet energy demands of field exercise?

With compensation for dehydration, average body weight loss or gain of platoon should not exceed 3 percent of initial body weight at any time during test.

Body weights measured accurately (± 0.2 kg) before and 2 × per day on 16 days during 44-d test.

Will troops fed CFFS-FDTE rations consume sufficient fluids and water to maintain hydration status?

Average urine specific gravities of a platoon should not exceed 1.030 at any time.

Overnight-fasting urine samples collected before and on 11 days during the 44-d test. Measured specific gravity, osmolality, and electrolytes and creatinine ratios.

Will troops maintain nutritional status?

No statistically significant (P < 0.05) increase in incidence of nutritional deficiency and no significant change in body composition, cholesterol or lipoprotein levels should occur.

Skinfolds; HDL, LDL, and total cholesterol and biochemical indices of acceptable, low, or deficient Vitamins A, C, thiamin, riboflavin, folic acid, and iron measured pre, and days 1, 20, and 44.

What is the incidence of food-related health disorders?

Investigative.

Environmental systems questionnaire administered before and once during each food intake collection period.

 

 

Monitor Medical treatment logs with follow up interviews of soldier complaints

Will muscle strength, muscular endurance, and eye-hand coordination be maintained?

Average strength endurance and coordination scores must not decrease more than 10 percent from initial values

Handgrip strength and endurance; maximal isometric upright pull force; maximal lift capacity; arm-hand steadiness; and ball-pipe test measured pre, and days 1, 20, and 44.

 

SOURCE: Adapted from USACDEC/USARIEM (1986).

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

TABLE 6-5 Standard Values Indicative of Nutritional Deficiencies

Parameter

Age/Sex Category

Deficient Level (High Risk)

Low Level (Medium Risk)

Acceptable Level (Low Risk)

Vitamin A

Plasma retinol (µg/100 ml)

All ages

<10

10–19

=20

Vitamin C

Serum ascorbic acid (mg/100ml)

All ages

<0.20

0.20–0.29

=0.30

Thiamin red blood cell transketolase

TPP effect, TPP* stimulation (%)

All ages

>20

16–20

0–15

Riboflavin red blood cell glutathione

Reductase FAD effect (activity coefficient)

All ages

>1.40

1.20–1.40

<1.20

Folic acid

Serum Folacin (ng/ml)

All ages

<3.0

3.0–5.9

=6.0

Hemoglobin (g/100ml)

Adult male

<12.0

12.0–13.9

=14.0

 

Adult female

<10.0

10.0–11.9

=12.0

Hemocrit (%)

Adult male

<37

37–43

=44

 

Adult female

<31

31–37

=38

Iron (three measures used deficiency = two of three abnormal)

(1) Transferrin saturation (%)

All ages

<15.0

15.0–19.9

=20.0

except infant

<16

 

=16

 

All adults

 

 

 

(2) Erythrocyte protoporphyrin (µ/dl red blood cell)

15–74 years

>70

 

<70

(3) Serum ferritin (ng/ml)

15–74 years

<12

 

=12

* TPP, thiamin pyrophosphate

† FAD, flavin adenine dinucleotide.

SOURCE: USACDEC/USARIEM (1986).

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

CMNR also reviewed and provided comments on the preliminary data in December 1985 prior to publication of the three-volume CFSS-FDTE Test Report (USACDEC/USARIEM, 1986) in January 1986. Robert Nesheim also was present for one of the briefings on the test results to general officers in the Pentagon during February 1986. The findings, conclusions, and recommendations from this study were briefed to the Chief of Staff and Vice-Chief of Staff of the Army in March 1986. The nutritional findings were that the troops consumed sufficient quantities of the CFFS-FDTE rations to meet their energy demands and consumed sufficient fluids to maintain hydration status. Calcium intakes of the female soldiers did not meet the MRDAs. Recommendations were made and adopted by the Army to increase the variety and quality of T Ration breakfast entrees and starches to encourage greater consumption, to increase the calcium content of the T Ration menus, and to add a beverage powder to the MRE to encourage optimal hydration while troops were subsisting on three MREs per day. The CMNR's comments and recommendations were included in their 1986 Annual Report (NRC, 1986).

1986 MRE Improvement Test—Hawaii

The next major field trial was the 1986 MRE Improvement Test, an 11-d field test conducted by USANRDEC and USARIEM to evaluate the effectiveness of MRE improvements to correct previously identified problems with inadequate consumption, excessive body weight loss, and possible dehydration. Because this test was of relatively short duration (11 days), the nutritional variables were limited to measuring energy, nutrient, and fluid intake; body weight change; and urine specific gravity for small groups of soldiers fed the current version of the MRE three times per day or two different versions of an improved MRE. The same body weight loss and hydration status criteria that were used in the 1985 CFFS-FDTE test were used in this test.

Results of the 1986 MRE Improvement Test (Popper et al., 1987) were also briefed to a General Officer Committee for a decision on whether to stay with the current MRE or to adopt one of the improved versions. Soldiers fed the improved MRE consumed more calories, lost less body weight, were better hydrated, and drank more total water than the current MRE group. The decision was made to incorporate the improvements that worked (e.g., add the beverage powder, increase the size of some of the entrees) into the next annual procurement of the MRE. This author raised the point at that briefing that energy intakes of the improved MRE, although increased by 325 kcal/d, were still approximately 700 kcal/d below the energy expenditures of the light infantry soldiers and that further improvements were still needed. Although the improvements in hydration status noted in this temperate environment test were encouraging, this author also noted that similar tests should be conducted in

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

more demanding hot and cold climates where problems with dehydration are more likely to occur.

1989 MRE Cold-Weather Supplement Test—Alaska

The 1989 MRE Cold-Weather Supplement Test was a 10-d field trial conducted by USARIEM and USANRDEC to evaluate the effectiveness of current and improved MRE rations, with or without a supplement, to maintain body weight, nutrient intakes, and hydration of light infantry soldiers conducting field training in extreme cold (-40¹F to +30¹F; -40¹C to -1¹C) temperatures. The nutritional criteria for this test were identical to those used in the 1986 MRE Improvement Test. The results (Edwards et al., 1990) indicated that the supplements increased energy intakes by approximately 700 kcal/d and reduced body weight losses to approximately 1.8 percent of body weight over the short 10-d period.

During the third and fourth days of this field trial, two of the units that were receiving the supplements had average urine specific gravities exceeding the 1.030 criterion. The urine specific gravities were high because the soldiers were consuming only about 1 to 1.5 liters of fluid per day compared to 3 to 4 liters per day for the other two groups. Upon investigation, the problem did not appear to be due to the supplement, but rather to a logistical problem. The two units did not get resupplied with unfrozen water, and they did not have the equipment with them to melt snow. Fluid intakes and urine specific gravities returned to normal as soon as the water resupply problem was resolved.

RECOMMENDATIONS

This author's experiences during the past 10 to 12 years of direct involvement in establishing nutritional criteria for field testing of operational rations have led to the following recommendations:

  • Nutritional standards for operational and restricted rations are appropriate nutritional criteria for development and procurement of military rations.

  • Military Recommended Dietary Allowances (MRDAs) are the appropriate criteria for the evaluation of the nutritional adequacy of nutrient intakes of male and female personnel who consume operational rations in field.

  • Field tests to determine if troops will consume more of one ration than another should be a minimum of 10 days in duration.

  • Field tests to evaluate whether troops will eat enough of the ration to meet their energy demands should be a minimum of 14 days but preferably 21- to 30-d duration.

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×
  • The appropriate criterion to evaluate whether troops will eat enough of the ration to meet their energy demands should be that the average body weight loss of the test unit does not exceed 3 percent of initial body weight.

  • An acute (1 to 2 days) average weight loss exceeding 3 percent is indicative of possible dehydration.

  • An average urine specific gravity exceeding 1.030 is indicative of inadequate fluid consumption and possible dehydration.

  • Average body weight losses for a unit of troops exceeding 5 percent of initial body weight may indicate an unacceptable risk of adverse health or performance.

  • Individuals who lose more than 10 percent of initial body weight during a field ration trial should be immediately referred for medical evaluation.

  • Field ration trials of more than 21-d duration should include biochemical assessment of nutritional status.

  • A new or major modification to an existing ration or feeding system should not to be implemented until it has been adequately tested in direct comparison with the old ration or system with troops during realistic field training maneuvers.

  • Field ration trials should also be conducted under extreme environmental conditions.

REFERENCES

AR (Army Regulation) 40-25 1985. See U.S. Departments of the Army, the Navy, and the Air Force, 1985.


Boaz, T.D. 1970. Untitled presentation at the Third Nutrition Symposium. March 2–6, Walter Reed Army Institute of Research, Washington, D.C.


Edwards, J.S.A., D.E. Roberts, J. Edinberg, and T.E. Morgan 1990. The Meal, Ready-to-Eat consumed in a cold environment. Technical Report T9–90. Natick, Mass.: U.S. Army Research Institute of Environmental Medicine.


Holbrook, L.R. 1916. The Mess Sergeant's Handbook, 4th ed. Menasha, Wisc.: George Banta Publishing Company.


Murlin, J.R., and C.W. Miller 1919. Preliminary results of nutritional surveys in United States Army Camps. Am. J. Public Health 9(6):401–413.


NRC (National Research Council) 1941. Recommended Dietary Allowances. Washington, D.C.: National Research Council.

1945. Recommended Dietary Allowances, Revised 1945. Reprint and Circular Series No. 122. Washington, D.C.: National Research Council

1964. Recommended Dietary Allowances, Sixth Revised Edition. Report of the Food and Nutrition Board, Publication 1146. Washington, D.C.: National Research Council.

1968. Recommended Dietary Allowances, Seventh Edition. Report of the Food and Nutrition Board, Publication 1694. Washington, D.C.: National Research Council.

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×

1974. Recommended Dietary Allowances, Eighth Revised Edition. Report of the Committee on Dietary Allowances and Committee on Interpretation of the Recommended Dietary Allowances, Food and Nutrition Board, Washington, D.C.: National Research Council.

1980. Recommended Dietary Allowances, Ninth Edition. Report of the Committee on Dietary Allowances, Food and Nutrition Board. Washington, D.C.: National Academy Press.

1985. Military Nutrition Research: Activity Report, September 30, 1983–September 30, 1985. Food and Nutrition Board, Commission on Life Sciences, National Research Council. Washington, D.C.: National Academy Press.

1986. Military Nutrition Research: Annual Report August 1, 1985–July 31, 1986. Food and Nutrition Board, Commission on Life Sciences, National Research Council. Washington, D.C.: National Academy Press.

Popper, R., E.S. Hirsch, L. Lesher, D. Engell, B. Jezior, B. Bell, and W.T. Matthew 1987. Field evaluation of Improved MRE, MRE VII, and MRE IV. Technical Report TR-87/027. Natick, Mass.: U.S. Army Natick Research, Development and Engineering Center.


Samuels, J.P., R.P. McDevitt, M.C. Bollman, W. Maclinn, L.M. Richardson, and L.G. Voss 1947. A Report on Wartime Problems in Subsistence Research and Development, Vol. 12, Ration Development. Chicago, Ill.: Quartermaster Food and Container Institute for the Armed Forces.


USACDEC/USARIEM (U.S. Army Combat Developments Experimentation Center and U.S. Army Research Institute of Environmental Medicine) 1986. Combat Field Feeding System-Force Development Test and Experimentation (CFFS-FDTE). Technical Report CDEC-TR-85-006A. Vol. 1, Basic Report; vol. 2, Appendix, A; vol. 3, Appendixes B through L. Fort Ord, Calif.: U.S. Army Combat Developments Experimentation Center.

U.S. Department of the Army 1945. Army Regulation 40-250. ''Nutrition." Washington, D.C.

1947. Army Regulation 40-250. "Nutrition." Washington, D.C.

1949. Army Regulation 40-250. "Nutrition." Washington, D.C.

1961. Nutrition. Technical Manual 8-501. Washington, D.C.

1971. Medical. Technical Bulletin 141. Washington, D.C.

1974. Rations. Technical Manual 8-250. Washington, D.C.

U.S. Departments of the Army, the Navy, and the Air Force 1968. Army Regulation 40-25/BUMED Instruction 10110.3/Air Force Regulation 160-95. "Nutritional Standards." Washington, D.C.

1969. Army Regulation 40-25/BUMED Instruction 10110.3A/Air Force Regulation 160-95. "Nutritional Standards." Washington, D.C.

1970. Army Regulation 40-25/BUMED Instruction 10110.3B/Air Force Regulation 160-95. "Nutritional Standards." Washington, D.C.

1976. Army Regulation 40-25/BUMED Instruction 10110.3E/Air Force Regulation 160-95. "Nutritional Standards." Washington, D.C.

1985. Army Regulation 40-25/Naval Command Medical Instruction 10110.1/Air Force Regulation 160-95. "Nutritional Allowances, Standards and Education." May 15. Washington, D.C.

U.S. War Department 1944. Nutrition. War Department Circular No. 98. Washington, D.C.

Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×
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×
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×
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×
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×
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×
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Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×
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Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×
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Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×
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Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×
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Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×
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×
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×
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×
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Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×
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Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×
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×
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×
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Suggested Citation:"6 Nutritional Criteria for Development and Testing of Military Field Rations: An Historical Perspective." Institute of Medicine. 1995. Not Eating Enough: Overcoming Underconsumption of Military Operational Rations. Washington, DC: The National Academies Press. doi: 10.17226/5002.
×
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Eating enough food to meet nutritional needs and maintain good health and good performance in all aspects of life—both at home and on the job—is important for all of us throughout our lives. For military personnel, however, this presents a special challenge. Although soldiers typically have a number of options for eating when stationed on a base, in the field during missions their meals come in the form of operational rations. Unfortunately, military personnel in training and field operations often do not eat their rations in the amounts needed to ensure that they meet their energy and nutrient requirements and consequently lose weight and potentially risk loss of effectiveness both in physical and cognitive performance. This book contains 20 chapters by military and nonmilitary scientists from such fields as food science, food marketing and engineering, nutrition, physiology, psychology, and various medical specialties. Although described within a context of military tasks, the committee's conclusions and recommendations have wide-reaching implications for people who find that job-related stress changes their eating habits.

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