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The Role of Protein and Amino Acids in Sustaining and Enhancing Performance (1999)

Chapter: 4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel

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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

Protein and Amino Acids, 1999

Pp. 93-108. Washington, D.C.

National Academy Press

4
Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel

LTC (ret) Alana D. Cline1 and John P. Warber

INTRODUCTION

Adequacy of nutrient intake by military personnel has been evaluated on a periodic basis since World War II; the responsibility for evaluating the nutritional status of military personnel and prescribing standards for operational rations has been that of the Army Surgeon General (U.S. Department of the Army, 1945; U.S. War Department, 1944). As new rations have been developed, their acceptability and effects on the health and performance of military personnel have been assessed. Subsequently, modifications have been recommended after evaluation of their nutritional impact.

The nutrient composition of operational rations is designed by food technologists at the U.S. Army Natick Research, Development and Engineering Center (NRDEC) to meet nutritional standards that are based on published

1  

Alana D. Cline, Military Nutrition and Biochemistry Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA 01760-5007. Currently of Pennington Biomedical Research Center, Baton Rouge, LA 70808.

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

recommendations such as the Recommended Dietary Allowances (NRC, 1980) and those of other recognized bodies of nutrition scientists. Ideally, rations should be designed to meet not only the minimum nutritional requirements, but the requirements for optimal nutrition. In practice, however, the requirements for optimal nutrition have yet to be determined, and may differ among individuals. During World War II, recommendations of the first Food and Nutrition Board (FNB) (NRC, 1941, 1945) were used as a metric for determining adequacy of the rations. Since 1947, standards have been specifically established for the military, based on the FNB Recommended Dietary Allowances (RDAs), and adapted for emerging physical requirements.

Food intake by military personnel has been monitored periodically over several decades to determine whether changes in consumption of various nutrients have occurred. Because of recent public interest in strength training and body building, which has been associated with increased intake of various protein and amine acid supplements by individuals who have the expectation that their muscle strength, size, and performance will improve, the Army has recently surveyed military personnel to determine the extent of supplement use.

What has not been determined is whether protein intake recommendations established during World War II and still used remain appropriate for military personnel today. A related question is what was the general range of protein intake by soldiers during that time, and how has it changed since those guidelines were initially established.

This chapter presents an overview of ration studies that were conducted during World War II and compares them with more recent studies on energy and protein intake and requirements of military personnel in garrison and operational settings. Reported consumption of amine acid and protein supplements will also be addressed, with frequency of consumption identified by gender, age, and military specialty.

PROTEIN AVAILABILITY FROM OPERATIONAL RATIONS

Operational rations have been divided into those prepared in field kitchens for groups of military personnel and those the individual soldier must carry, prepare, and consume. By design, they provide an excess of calories and protein, when possible, to allow for some food choice by the individual and still allow for adequate nutrient intake (Samuels et al., 1947). Former and current rations most widely used for tactical consumption are compared in Table 4-1.

The individual ration most widely used during World War H was the C Ration, which provided a combination of canned foods and packaged dehydrated or dried foods. Nutritional composition was 2,794 kcal and 121 g protein. To provide a ration with the greatest caloric density in the smallest weight and space, the K Ration was developed in 1941; it provided 2,842 kcal and 79 g protein.

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

TABLE 4-1 Energy and Protein Content of Operational Rations

Ration Type

Energy (kcal)

Protein (g)

% Energy

C Ration

2,794

121

17

K Ration

2,842

79

11

5-1

3,383

98

12

10-1

4,188

124

12

B Ration

4,300

140

13

MRE

3,819

136

14

UGR

3,973

142

14

Ration, Cold Weather

4,500

90

8

Go-to-War Ration

3,600

144

16

NOTE: 5-1, Five-in-One; 10-1, Ten-in-One; MRE, Meal, Ready-to-Eat; UGR, Unitized Group Ration.

The most widely used rations packaged for group feeding in World War II were the Five-in-One Ration (5-1), providing 3,383 kcal and 98 g protein, and the Ten-in-One Ration (10-1), providing 4,188 kcal and 124 g protein. These rations were designed to provide adequate food for 1 day's consumption by a unit of 5 or 10 men, respectively, and required minimal food preparation for small groups of individuals away from food preparation facilities. The B Ration was developed to provide foods in bulk for a minimum of 100 individuals. It comprised packages and cans of bulk foods not requiring refrigeration, but needing reconstitution or rehydration during meal preparation. A series of 10 days' menus were provided, complete with recipes. Kitchen-prepared A (perishable foods, needing refrigeration) or B Rations were those on which the military depended for regular daily feeding; they were required to be fully adequate for all nutrients, meeting standards set by the National Research Council to provide at least 3,000 kcal and 70 g protein.

Current operational rations include the MRE for individual consumption and the UGR for group feeding, each exceeding the operational ration standards of 3,600 kcal and 100 g protein (AR 40-25, 1985). In addition, vegetarian MRE meals have been recently added (2/case of 12) to provide choices for individuals not consuming meat products. The Ration, Cold Weather (4,500 kcal, 90 g protein) is used to sustain an individual during operations occurring under frigid conditions, and the Go-to-War Ration (3,900 kcal, 156 g protein) was designed for the early stages of mobilization until such time that the ration industry can meet deployment demands. Both rations are designed to provide short-term support, so they do not meet the full nutritional requirements for operational rations.

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

HISTORIC RATION INTAKE

Major ration studies from 1941 to 1946 utilized several methods of data collection for troops deployed worldwide to varying environmental conditions. Techniques used for data collection included both field tests and individual and group surveys conducted on site; most subjects were Army soldiers, with the exception of several Air Force units and flight crews.

Studies evaluating male soldiers during World War H reported mean intakes of energy in garrison ranging from 3,400 to 3,800 kcal with protein intake from 110 to 132 g; intakes during field training were similar: 3,200 to 4,100 kcal and 100 to 125 g protein, with percentage of energy from protein at 13 percent for both garrison and field (Table 4-2).

In one of the first rigorous ration tests during World War II (Johnson and Kark, 1946), the B Ration was tested (Camp Lee, Va.) on soldiers who were placed on a rigid activity program that would reflect the ordinarily increased energy expenditure of deployment. During the pre-experimental or control period, test subjects consumed dining hall A Rations and participated in a work schedule that resulted in an estimated energy expenditure of 3,100 kcal/d. Energy intake (3,800 kcal) was highest during the control phase of the study while protein intake was 116 g (Table 4-2). As the physical activity schedule

TABLE 4-2 Energy and Protein Intake by Male Soldiers: Selected Trials 1940s

Study

N

Ration Type

Energy (kcal)

Protein (g)

%

Energy

Camp Lee, 1943 (G)*, (Johnson and Kark, 1946)

65

A

3,800

116

12.2

Camp Lee, 1943 (G), (Johnson and Kar, 1946)

65

B

3,600

132

14.7

Mess Survey, 1941-1943 (G), (Howe and Berryman, 1945)

A

3,790

125

13.2

Camp Carson, 1944 (F), (Bean et al., 1944)

118

B

3,930

125

12.7

Camp Carson, 1944 (F), (Bean el al., 1944)

125

10-1

4,100

125

12.2

Pacific Islands, 1945 (G), (Bean et al., 1946)

50

A

3,400

110

12.9

Luzon, 1945 (F), (Bean et al., 1946)

50

C

3,200

100

12.5

Average (G)

 

 

3,648

1 21

13.3

Average (F)

 

 

3,743

117

12.5

* G = Garrison study.

‡ F = Field study.

† Calculated from average ration intake from 455 garrison messes.

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

became more intense (4,000 kcal) during the test period, energy intake actually decreased while protein intake increased. Although the B Ration offered during the test phase provided 3,800 kcal, soldiers consumed only 3,600 kcal, and 132 g protein and generally complained of hunger.

Additional food consumption studies conducted at U.S. Army training camps from 1941 to 1943 were reported by Howe and Berryman (1945). Surveys took place at 50 posts and 455 mess facilities using the difference between weights of food issued and food discarded or wasted. Although consumption of foods away from the mess was not recorded, it was estimated that 350 to 400 kcal/d were purchased at the canteen or were received in personal packages. Results again showed a daily consumption of approximately 3,800 kcal of energy and 125 g of protein.

In 1944, acceptability and adequacy of several field rations were tested at 2,700 m elevation in the Rocky Mountains with Army troops from Camp Carson during summer maneuvers. Daily energy intake ranged from 2,880 kcal for a small group consuming the K Ration to 4,100 kcal, with protein intake averaging 12 percent of energy (110-125 g). Over a study period of 55 days, measurements of physical fitness, nutritional status, biochemical indices, and rifle firing all improved, with no differences seen between ration types (Bean et al., 1944).

Surveys of the health, fitness, and nutrition of troops in the Pacific were conducted in 1945 to compare nutrient intake of noncombat garrison soldiers with those who had been in combat continuously for 41/2 months. Average nutrient intake of garrison soldiers in the Pacific was similar to intake by soldiers in training camps in the United States, in part due to ample supplies of fresh and frozen foods. Troops living exclusively on packaged rations (C Rations) in Luzon had a daily caloric intake 200 to 300 kcal less than garrison troops, but protein intake remained similar among the soldiers at 13 percent of total energy consumed (Bean et al., 1946).

CURRENT RATION INTAKE

More recent (1994-1996) studies have reported intakes by men in garrison ranging from 2,773 to 3,173 kcal and 98 to 132 g protein, averaging 15.2 percent of energy from protein; field intakes have ranged from 2,009 to 3,050 kcal and 86 to 126 g protein, or 16 percent of energy from protein (Table 4-3). Intakes by women have also been reported, with intakes in garrison ranging from 1,832 to 2,592 kcal and 75 to 96 g protein, and intakes in field exercises ranging from 1,668 to 2,343 kcal and 68 to 82 g protein, with approximately 15 percent of energy from protein in both garrison and field assessments (Table 4-4). It should be noted that mean weight of male soldiers increased from 68.4 kg in the 1940s to a current mean weight of 78.9 kg; current mean weight of female soldiers is 63.6 kg. In data recently collected from the Army Food and

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

TABLE 4-3 Energy and Protein Intake by Male Soldiers: Recent Studies

Study

N

Ration Type

Energy (kcal)

Protein (g)

% Energy

Pohakuloa, 1984 (F)*, (Askew et al., 1986)

 

MRE

2,273

99

17.4

Ft. Riley, 1986 (G), (Szeto et al., 1987)

43

A

3,112

123

15.8

Ft. Lewis, 1986 (G), (Szeto et al., 1987)

31

A

3,173

125

15.8

Ft. Devens I, 1987 (G), (Szeto et al., 1988)

54

A

2,978

111

14.9

Ft. Devens II, 1988 (G), (Szeto et al., 1989)

52

A

3,165

132

16.6

Alaska, 1989 (F), (Edwards et al., 1989)

31

MRE

2,009*

91§

NA

Ft. Chaffee, 1991 (F), (Thomas et al., 1995)

34

MRE + pouch bread

2,462

103

16.7

Ft. Chaffee, 1991 (F), (Thomas et al., 1995)

32

A

2,911

126

17.3

Chocolate Mtn., (F), (Tharion et al., 1997) 1994

31

UGR

2,631

105

15.9

Chocolate Mtn., 1994 (F), (Tharion et al., 1997)

32

UGR + Suppl

3,050

93

12.2

Ft. Polk, 1995 (G), (Cline et al., 1997)

38

A

3,003

103

13.7

Hunter Army Airfield, 1996 (G), (Champagne et al., 1997)

73

A

2,773

98

14.1

Hunter Army Airfield, 1996 (F), (Champagne et al., 1997)

31

MRE

2,439

86

14.1

Average G

 

 

3,034

115

15.2

Average F

 

 

2,587

104

16.1

NOTE: MRE, Meal Ready-to-Eat; UGR, Unitized Group Ration; NA, not available.

* F = Field study.

† G = Garrison study.

‡ Carbohydrate beverage supplement provided ad libitum.

§ Data reported as mean of days, not mean of individuals.

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

TABLE 4-4 Energy and Protein Intake, Female Soldiers

Study

N

Ration Type

Energy (kcal)

Protein (g)

% Energy

Ft. Lewis, 1987 (G)*, (Szeto et al., 1987)

12

A

1,832

75

16.4

Ft. Jackson, 1988 (G), (R.W. Rose et al., 1989)

40

A

2,467

96

15.6

Ft. Hood, 1988 (F), (M.S. Rose et al., 1989)

27

2B + 1MRE

2,343

82

14.0

Bolivia, 1990 (F), (Edwards et al., 1991)

13

2B + 1MRE

1,668

68

16.3

Ft. Jackson, 1993 (G), (King et al., 1994)

49

A

2,592

82

12.7

Ft. Sam Houston, 1995 (G), (Cline et al., 1998)

56

A

2,037

75

14.7

Camp Parks, 1996 (F), (Hirsch et al., in press)

19

MRE

2,161

82

15.2

Average G

 

 

2,232

82

14.9

Average F

 

 

2,057

77

15.0

NOTE: MRE, Meal Ready-to-Eat.

* G = Garrison study.

† These soldiers in basic training course.

‡ F = Field study.

Nutrition Survey I (Warber et al., 1996) at 33 Army installations worldwide, over one-fourth (26%) of male respondents and nearly one-third (31%) of female respondents replied that they used field feeding as a way to lose weight.

Energy and Protein Intakes of Military Men

Infantry soldiers from Fort Shafter, Hawaii, participated in a study at Pohakuloa Training Area, Hawaii (2,160 m), to determine the adequacy of the Meal, Ready-to-Eat (MRE) during strenuous cross-country running under high-altitude field conditions (Askew et al., 1986). During the 10-d exercise, soldiers consumed less than 67 percent of calories recommended for energy balance and lost 3 percent of their body weight, 10 percent of their body fat, and experienced a 5 percent decline in maximal aerobic capacity. Protein intake was 99 percent of recommended intake. By comparison, infantry soldiers training in Alaska

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

under winter conditions were assessed for adequacy of nutritional intake over a 10-d field training exercise. Although individuals were given 4 MREs/d, consumption again remained significantly lower than the Military Recommended Dietary Allowances (MRDAs) for energy and protein (Edwards et al., 1989).

Because of concerns that logistical problems with food supply may require individuals to subsist solely on the MRE for up to 30 days, a study was conducted at Fort Chaffee, Arkansas, to assess the ability of the MRE to meet soldiers' nutritional needs and maintain performance in a field environment for an extended period (Thomas et al., 1995). Participants were combat engineers on a regularly scheduled 30-d field training exercise; they were divided into one group eating three MREs and two pouch bread (190 kcal, 5 g protein each) per day and one group eating two A Rations and one MRE per day. Nearly one-third of the subjects indicated they wanted to lose weight during the training exercise, and this was reflected in a low mean energy intake of 2,462 kcal for the MRE group and 2,911 kcal for the A Ration group. Even with incomplete consumption of the MREs provided, soldiers in both groups obtained 100 percent of their MRDA for protein and demonstrated a positive nitrogen balance, which indicates that although caloric intake was low, performance and overall nutritional status were not impaired when soldiers consumed only MREs for 30 days.

A test was conducted with a Marine battery-sized field artillery unit in 1994 at Chocolate Mountain Desert Gunnery Range, California (Tharion et al., 1997). The primary purpose of the test was to assess the ability of the new Unitized Group Ration (UGR) to meet nutritional requirements of individuals working in a desert environment. The UGR used in this study was a combination of A, B, and T Rations, which provided hot meals in a group feeding setting for two meals per day, with the third meal a MRE. Either a carbohydrate or a placebo beverage was also provided ad libitum to two supplemental groups to assess effects of additional nutrient intake and hydration status. In the placebo group, mean energy intake was 73 percent of MRDA (2,631 kcal), while protein intake was 105 percent (105 g). Although protein intake appeared to be adequate, energy intake was well below the calculated energy expenditure of approximately 4,300 kcal/d. The carbohydrate beverage did increase mean daily energy consumption (3,050 kcal), but protein intake was lower (93 g). This study provides further evidence that even when troops in field training exercises are provided two hot meals per day and consume adequate protein, their caloric intake may be inadequate for energy needs.

Alternately, studies of nutrient intake in garrison dining facilities continue to show that soldiers are consuming adequate energy and protein. Reports on assessment of nutritional status of soldiers at Fort Riley, Kansas; Fort Lewis, Washington (Szeto et al., 1987); and Fort Devens, Massachusetts (Szeto et al., 1988, 1989), concluded that dining facility consumption provided adequate daily energy and protein intakes for individuals, even when some meals and

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

snacks were being consumed elsewhere. By contrast, air defense artillery soldiers at Fort Polk, Louisiana (Cline et al., 1997) consumed only approximately half of their meals in the dining facility. Overall nutrient intake from all foods, including those consumed elsewhere, was adequate in energy and protein. Nutrient intakes were reported to be 3,091 kcal and 105 g protein, with 13.6 percent of total energy obtained from protein. Although mean energy intake was below the MRDA, protein intake was adequate.

A nutritional assessment of Army Rangers at Hunter Army Airfield in 1996 was the first of an Army Special Operations unit (Champagne et al., 1997). Rangers are routinely involved with extensive deployments and field training exercises. This study was designed to compare dietary intake of Rangers before deployment with that during a field training exercise and during recovery after return. Phase I (predeployment) assessed a group subsisting in a garrison dining facility for the 6 days immediately prior to deployment on the exercise, while Phase II (training) assessed the dietary intake of the same unit during the 6-d field training exercise while consuming MREs (Table 4-3). Phase III assessed postdeployment garrison intake of a subgroup (n = 40) of subjects for the 2 days immediately after return from the field; mean recovery intake was 2,965 kcal and 98 g protein (13.2% of total energy). Mean energy and protein intakes for all phases were lower than what have been reported on previous studies. As with the soldiers at Fort Polk, a substantial amount of food (33% of energy) was consumed away from the dining facility. This trend is similar to eating patterns reported in national nutrition monitoring studies of eating patterns of nonurban households, where more than one-third of total food dollars were spent on food away from home (Interagency Board, 1993).

Energy and Protein Intakes of Military Women

Until recently, few studies have assessed nutritional intake of military women during field exercises or deployment. Women who were members of an Army engineering group deployed to high altitude in Bolivia were assessed for nutrient intake while consuming a combination of two B Ration meals and one MRE per day. They were also given a high-carbohydrate supplemental pack to consume between meals to determine whether increased carbohydrate intake was preferable at high altitude. Energy and protein intake were well below MRDA; approximately half of the subjects indicated they had acute mountain sickness (AMS) symptoms, which most likely affected appetite (Edwards et al., 1991).

Two field studies that included women as subjects were completed with Army Reserve hospitals conducting their annual field training exercises and subjects consuming operational rations. At Fort Hood, Texas, two A Ration meals and one MRE per day were provided during an 8-d test period; individuals also had access to additional foods they brought or that could be purchased from a PX mobile kitchen or fast-food establishments in the vicinity

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

of the field site. Although 26 percent of the subjects stated that they were attempting to lose weight during the training exercise, mean energy intake was 2,343 kcal and mean protein intake was 82 g, both of which exceeded the MRDA for women (M.S. Rose et al., 1989). Similar results were reported in an Army Reserve hospital unit training at Camp Parks, California (Hirsch et al., in press).

When comparing nutrient intakes between women in enlisted basic training at Fort Jackson, South Carolina (R.W. Rose et al., 1989; King et al., 1994) and women in officer basic training at Fort Sam Houston, Texas (Cline et al., 1998), a difference was observed in both energy and protein intakes. Meals for enlisted women are provided in a dining facility at scheduled times, with free access to a variety of food selections. Alternately, officers are given a monetary allowance to purchase food, but they live in temporary housing, such as motels or officers quarters, that has limited or no cooking facilities. This could account for lower energy and protein intake by the officers. No recent studies have been completed on nutrient intake of career military women in garrison.

DETERMINATION OF PROTEIN REQUIREMENTS FOR OPERATIONAL RATIONS

The first standard recommendations for nutrient requirements for military personnel were formulated by the FNB of the National Research Council, a project that was organized in 1940 in connection with the defense program (Samuels et al., 1947). Recommendations by the board addressed allowances needed to maintain optimal nutritional status. Of concern was the fact that rations designed for short-term use, not previously required to be nutritionally adequate, were being used over long periods of time. Maximum nutrient availability was emphasized in all but a few of the survival rations.

The standard originally established for protein was 70 g/3,000 kcal, for a reference man weighing 70 kg. This recommendation was equivalent to 9 percent of energy from protein, and 0.8 to 1.0 g/kg of body weight (kcal requirements of 3,000-3,600). After reviewing research on energy consumption and expenditure of soldiers during World War II, the Army raised energy requirements to 3,600 kcal for physically active personnel in temperate climates, with a protein requirement of 100 g (AR 40-250, 1947). The RDA (NRC, 1989) for protein is 58 to 63 g for males and 46 to 50 g for females in the age categories of military personnel; recommendations are lower because reference weights and activity levels used for calculations are less than those for the military population.

Several investigators have recommended that the RDA for protein be increased to 1.5 g/kg for endurance athletes and to 2.0 g/kg for strength athletes (Brotherhood, 1984; Williams, 1995; Lemon, 1996). Recent research has shown an increase in the weight of Army soldiers from 68 to 78 kg for men and 61 to 62 kg for women (Gordon et al., 1989) which would increase recommendations

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

to 117 g of protein (1.5 g/kg) for operational rations if soldiers are involved in heavy work. If protein in rations is increased to accommodate recommendations of 1.5g/kg for endurance activity in men, it would contribute 13% of food energy at the 3,600 kcal level. Food consumption data on the U.S. population from NHANES III (Third National Health and Nutrition Examination Survey) indicate that 14 to 16 percent of the total food energy intake is derived from protein (Interagency Board, 1995). This proportion remains similar for both sexes.

Energy requirements should be evaluated with full consideration of the fuel necessary to balance energy expenditure. For example, energy expenditure during field operations for Special Forces students has been reported at levels up to 6,000 kcal/d (Shippee et al., 1994).

SUPPLEMENT INTAKE

In data from the Army Food and Nutrition Survey I (Warber el al., 1996) at 33 Army installations worldwide, supplementation with amino acid (AA) products or protein powders (PP) was reported by military members, with usage differing by age and military job specialty (Table 4-5). Individuals less than 30 years old reported the highest use by age, with approximately one-third using both types of products. When classified by military job specialty, individuals in combat arms reported the highest usage, followed by combat service support and combat support. Percentages of men using AA (33% vs. 16%) or PP (27% vs. 11%) are at least double that of women, and individuals required to eat in military dining facilities report a higher percentage of usage (AA = 35%, PP = 29%) than those who receive food allowances to eat elsewhere (AA = 30%, PP = 24%).

Many amino acid and protein powder supplements have become available for purchase in military commissaries and exchanges, as well as in fitness centers on military installations. Newly established ''nutrition store" franchises are also opening on numerous bases, offering products with a myriad of claims for benefit to performance. An expanding selection of fitness magazines is also available for purchase, providing advertisements as well as feature articles on claims of the benefits of the protein and amino acid products. Thus, military personnel have increased their consumption of these products because of their desire to improve physical performance and the belief that they will receive some benefit from using them on a regular basis.

Considerable variability persists, however. During a nutrient intake study at Fort Polk, Louisiana, in 1995 (Cline et al., 1997), only 4 percent of young male soldiers in an Air Defense Artillery company replied that they were using protein supplements. These responses contrasted with a 44 percent consumption rate among Army Rangers participating in a similar study at Hunter Army Airfield, Georgia, in 1996 (Unpublished data, J.P. Warber, USARIEM, Natick, Mass, 1997).

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

TABLE 4-5 Percentage of Military Personnel Reporting Use of Protein Supplements

Group (N)

Amino Acids (%)

Protein Powders (%)*

Men (1,941)

33

27

Women (291)

16

11

Age < 30 yr (1,238)

36

30

Age > 30 yr (1,040)

26

19

Combat Arms (784)

38

32

Combat Service Support (949)

28

22

Combat Support§ (536)

27

20

No Separate Rations" (545)

35

29

Separate Rations# (1,546)

30

24

SOURCE: Data from Warber et al., 1996.

* Some respondents reported consumption of both amino acids and protein powders.

† Infantry, Armor, Field Artillery, Air Defense, Special Forces.

‡ Ordnance, Quartermaster, Transportation, Adjutant, Chaplain, Finance, Judge Advocate General, Inspector General, Medical Department.

§ Engineer, Chemical, Military Intelligence, Military Police, Signal, Aviation, Civil Affairs.

" Meals provided in military dining facility.

# Salary provides for purchase of foods of choice.

In a recent study on women entering the Army for basic training, only 2 of 105 replied that they had consumed supplemental protein products prior to entry for training (Cline and Pusateri, 1996). Women who have been on active duty for a longer period of time have reported a much higher rate of consumption (Table 4-5), leading one to question whether they have been influenced by the performance and fitness attitudes of their male counterparts with whom they exercise.

AUTHORS' CONCLUSIONS AND RECOMMENDATIONS

Male military personnel maintain high protein intakes from food consumption in garrison as well as during field operations. Females, however, generally consume less energy and protein than MRDA guidelines require during field exercises where access to foods is limited to operational rations.

Protein supplements are being used by a substantial number of military personnel, although no documented benefits from their use have been reported. This practice has been encouraged by easy access to products for purchase on military installations and a very active informal information network among military personnel that indicates perceived benefits of these products.

What has not been addressed in detail is whether a change has taken place in the food contribution of protein. Is the highest proportion of protein consumed provided by meats and dairy products, or have other food groups

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

gradually replaced these in their contribution of protein to the diet? Dietary protein quality and digestibility of proteins in specific foods consumed need further investigation.

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Brotherhood, J.R. 1984. Nutrition and sports performance. Sports Med. 1:350-389.


Champagne, C.M., J.P. Warber, and H.R. Allen. 1997. Dietary intake of U.S. Army Rangers: Estimation of nutrient intake before and after field training. Presented at the XVI International Congress of Nutrition, Montreal.

Cline, A.D., and A.E. Pusateri. 1996. Comparisons of iron status, physical activity, and nutritional intake of women entering Army officer and enlisted basic training. Proceedings of 21st National Nutrient Databank Conference, Baton Rouge, La.

Cline, A.D., J.P. Warber, and C.M. Champagne. 1997. Assessment of meal consumption behaviors by physically active young men dining in a cafeteria setting. Presented at Experimental Biology Annual Meeting, New Orleans, LA. FASEB J; 11:A184.

Cline, A.D., J.F. Patton, W.J. Tharion, S.R. Strowman, C.M. Champagne, J. Arsenault, K.L. Reynolds, J.P. Warber, C. Baker-Fulco, J. Rood, R.T. Tulley, and H.R. Lieberman. 1998. Assessment of the relationship between iron status, dietary intake, performance, and mood state of female Army officers in a basic training population. Technical Report No. T98-24. Natick, Mass.: U.S. Army Research Institute of Environmental Medicine.


Edwards, J.S.A., E.W. Askew, N. King, C.S. Fulco, R.W. Hoyt, and J.P. DeLany. 1991. An assessment of the nutritional intake and energy expenditure of unacclimatized U.S. Army soldiers living and working at high altitude. Technical Report No. T10-91. Natick, Mass.: U.S. Army Research Institute of Environmental Medicine.

Edwards, J.S.A., D.E. Roberts, T.E. Morgan, and L.S. Lester. 1989. An evaluation of the nutritional intake and acceptability of the Meal, Ready-To-Eat consumed with and without a supplemental pack in a cold environment. Technical Report No. T18-89. Natick, Mass.: U.S. Army Research Institute of Environmental Medicine.


Gordon, C.C., T. Churchill, C.E. Clauser, B. Bradtmiller, J.T. McConville, I. Tebbetts, and R.A. Walker. 1989. 1988 Anthropometric survey of U.S. Army personnel: Methods and summary statistics. Technical Report No. TR-89/044. Natick, Mass.: U.S. Army Natick Research, Development and Engineering Center.

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

Hirsch, E., W. Johnson, P. Dunne, C. Shaw, N. Hotson, W. Tharion, H. Lieberman, R. Hoyt, and D. Dacumos. In Press. The effects of diet composition on food intake, food selection, and water balance in a hot environment. Technical Report. Natick, Mass.: Natick Research, Development and Engineering Center.

Howe, P.E., and G.E. Berryman. 1945. Average food consumption in the training camps of the United States Army. Am. J. Physiol. 144:588-594.


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Interagency Board (Interagency Board for Nutrition Monitoring and Related Research). 1995. Third Report on Nutrition Monitoring in the United States, vol. 2. Life Sciences Research Office, Federation of American Societies for Experimental Biology. Washington, D.C.: U.S. Government Printing Office.


Johnson, R.E., and R.M. Kark. 1946. Feeding problems in man as related to environment: An analysis of United States and Canadian Army ration trials and surveys, 1941-1946. Research Report. Chicago, Ill.: Quartermaster Food and Container Institute for the Armed Forces, Research and Development Branch, Office of the Quartermaster General.


King, N., J.E. Arsenault, S.H. Mutter, C.M. Champagne, T.C. Murphy, K.A. Westphal, and E.W. Askew. 1994. Nutritional intake of female soldiers during the U.S. Army basic combat training. Technical Report No. T94-17. Natick, Mass.: U.S. Army Research Institute of Environmental Medicine.


Lemon, P.W. 1996. Is increased dietary protein necessary or beneficial for individuals with a physically active lifestyle? Nutr. Rev. 54:169-175.


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

NRC. 1945. Recommended Dietary Allowances. Washington, D.C.: National Academy Press.

NRC. 1980. Recommended Dietary Allowances, 9th ed. Washington, D.C.: National Academy Press.

NRC. 1989. Recommended Dietary Allowances, 10th ed. Washington, D.C.: National Academy Press.


Rose, R.W., C.J. Baker, W. Wisnaskas, J.S.A. Edwards, and M.S. Rose. 1989. Dietary assessment of U.S. Army basic trainees at Fort Jackson, South Carolina. Technical Report No. T6-39. Natick, Mass.: U.S. Army Research Institute of Environmental Medicine.

Rose, M.S., P.C. Szlyk, R.P. Francesconi, L.S. Lester, L. Armstrong, W. Matthew, A.V. Cardello, R.D. Popper, I. Sils, G. Thomas, D. Schilling, and R. Whang. 1989. Effectiveness and acceptability of nutrient solutions in enhancing fluid intake in the heat. Technical Report No. T10-89. Natick, Mass.: U.S. Army Research Institute of Environmental Medicine.


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

Shippee, R., E.W. Askew, M. Mays, B. Fairbrother, K. Friedl, J. Vogel, R- Hoyt, L. Marchitelli, B. Nindl, P. Frykman, L. Martinez-Lopez, E. Bernton, M. Kramer, R. Tulley, J. Rood, J. DeLany, D. Jezior, and J. Arsenault. 1994. Nutritional and immunological assessment of Ranger students with increased caloric intake. Technical Report No. T95-5. Natick, Mass.: U.S. Army Research Institute of Environmental Medicine.

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

Szeto, E.G., D.E. Carlson, T.B. Dugan, and J.C. Buchbinder. 1987. A comparison of nutrient intakes between a Ft. Riley contractor-operated and n Ft. Levis military-operated garrison dining facility. Technical Report No. T2-88. Natick, Mass.: U.S. Army Research Institute of Environmental Medicine.

Szeto, E.G., T.B. Dugan, and J.A. Gallo. 1988. Assessment of habitual diners' nutrient intakes in a military-operated garrison dining facility. Ft. Devens I. Technical Report No. T3-89. Natick, Mass.: U.S. Army Research Institute of Environmental Medicine.

Szeto, E.G., J.A. Gallo, and K.W. Samonds. 1989. Passive nutrition intervention in a military-operated garrison dining facility. Ft. Devens II. Technical Report No. T7-89. Natick, Mass: U.S. Army Research Institute of Environmental Medicine.


Tharion, W.J., A.D. Cline, N. Hotson, W. Johnson, P. Niro, C.J. Baker-Fulco, S. McGraw, R.L. Shippee, T.M. Skibinski, R.W. Hoyt, J.P. Delany, R.E. Tulley, J. Rood, W.R. Santee, S.H.M. Boquist, M. Bordic, M. Kramer, S.H. Slade, and H.R. Lieberman. 1997. Nutritional challenges for field feeding in a desert environment: Use of the Unitized Group Ration (UGR) and a supplemental carbohydrate beverage. Technical Report No. T97-9. Natick, Mass.: U.S. Army Research Institute of Environmental Medicine.

Thomas, C.D., K.E. Friedl, M.Z. Mays, S.H. Mutter, R.J. Moore, D.A. Jezior, C.J. Baker-Fulco, L.J. Marchitelli, R.T. Tulley, and E.W. Askew. 1995. Nutrient intakes and nutritional status of soldiers consuming the Meal, Ready-To-Eat (MRE XIII) during a 30-day field training exercise. Technical Report No. T95-6. Natick, Mass.: U.S. Army Research Institute of Environmental Medicine.


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Discussion

PATRICK DUNNE: The Savannah study subjects, in part, were by design a test population who consumed a diet that was purposefully lower in protein but higher in carbohydrate. I think we need to look at the trade-offs here because we got them to achieve well above the military 400 grams of carbohydrate intake, and it was designed to be a hot-weather study. So that was a designed diet, not a free choice; it was rather selective. What we really want to do is look at impact and overall turnover of water and hydration as part of that study. Jim hopefully has some data for us on that.

I think that one of the drivers that leads the ration developers and the logistics community to look at protein is not just performance but it is actually the cost of the ration. So there are some major trade-offs in overall metabolism. If you want to trade protein for carbohydrate, maybe that is good, but not protein for fat. That was our design.

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×

ALANA CLINE: The data that I used for that study actually were from the control group that did not have the higher carbohydrate intake. The protein intake was even lower with the test group. So I went ahead and just used the control group for that and it is still a little bit lower.

DOUGLAS WILMORE: Thank you for the presentation. Do you have information on the source of the dietary protein over the period of 30 years or so?

ALANA CLINE: I do not have the historical data on the source of the protein. Some of our more recent studies are showing that there is a higher intake now of protein from non-meat sources. That is something that we would want to consider because there is a difference in the quality of the protein that is being consumed. That is something that we do need to look at more closely.

DOUGLAS WILMORE: So we have no idea about protein efficiency?

ALANA CLINE: Not for the historical data.

ROBERT NESHEIM: One last question.

ROBERT WOLFE: On that slide showing. voluntary intake of supplements you had two columns, amino acids and protein, and one was like 36 percent and the other was 30. Does that mean that 36 percent were taking amino acids and a separate 30 percent were taking protein.

ALANA CLINE: Yes. There were two separate questions.

ROBERT WOLFE: So that was the total of the two things they were taking in terms of dietary supplements?

ALANA CLINE: No, I am sorry. It was either one or the other. So it would be about 30 percent. They could be taking both, We were not able to really clarify that with the questionnaire that we had.

Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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Suggested Citation:"4 Overview of Garrison, Field, and Supplemental Protein Intake by U.S. Military Personnel." Institute of Medicine. 1999. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. Washington, DC: The National Academies Press. doi: 10.17226/9620.
×
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It is a commonly held belief that athletes, particularly body builders, have greater requirements for dietary protein than sedentary individuals. However, the evidence in support of this contention is controversial. This book is the latest in a series of publications designed to inform both civilian and military scientists and personnel about issues related to nutrition and military service.

Among the many other stressors they experience, soldiers face unique nutritional demands during combat. Of particular concern is the role that dietary protein might play in controlling muscle mass and strength, response to injury and infection, and cognitive performance. The first part of the book contains the committee's summary of the workshop, responses to the Army's questions, conclusions, and recommendations. The remainder of the book contains papers contributed by speakers at the workshop on such topics as, the effects of aging and hormones on regulation of muscle mass and function, alterations in protein metabolism due to the stress of injury or infection, the role of individual amino acids, the components of proteins, as neurotransmitters, hormones, and modulators of various physiological processes, and the efficacy and safety considerations associated with dietary supplements aimed at enhancing performance.

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