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OCR for page 17
1
Background and Context of the
Overweight Problem
Considerable attention has been given to the alarming rise in the incidence
of overweight and obesity in the U.S. population, both in the scientific literature
and in the popular press. The prevalence of overweight and obesity, defined as a
body mass index (BMI = weight [kg] divided by height tm]2 ~ from 25 to 29.9
and 30 or higher, respectively, was relatively stable from 1960 to 1980. How-
ever, data from the Third National Health and Nutrition Examination Survey
(NHANES III) from 1988-1994 showed an increase in the prevalence of over-
weight and obesity from 47 percent to 56 percent and a rise in the prevalence of
obesity from approximately 15 percent to 23 percent (Flegal et al., 1998; Kucz-
marski et al., 1994~. More recent data indicate that these trends have continued.
THE CURRENT NATIONAL SITUATION
The latest NHANES data from 1999-2000 (Flegal et al., 2002) show that
64.5 percent of the U.S. population 20 years of age and older is now classified as
overweight or obese. The prevalence of obesity (BMI 2 30) has risen from 23
percent to 30.5 percent. These trends are seen across both sexes and all ethnic
groups, with the greatest increases occurring in non-Hispanic Black females.
Furthermore, since 1980, the percentage of adolescents (ages 12-19 years) who
are overweight has tripled from 5 percent to 15.5 percent (Ogden et al., 20029.
There are some disparities however; overweight and obesity are particularly
common among minority groups and those with lower family income and less
education (HHS, 2001~.
The epidemic of overweight and obesity in the civilian population, which
many experts attribute to the ready availability of a vast array of foods combined
with an increasingly sedentary lifestyle, affects the military services of the
United States in two significant ways. First, it decreases the pool of individuals
eligible for recruitment into the military services, and second, it decreases
retention almost 80 percent of recruits who exceed the accession weight-for-
17
OCR for page 18
18
WEIGHT MANAGEMENT
height standards at service entry leave the military early (i.e., by year 2 of a 3 -
year term of enlistment).
Another important consideration of the impact of overweight and obesity is
their effect on chronic disease. Studies of the relationship between health and
disease have used the premise that a BMI of less than 18.5 constitutes under-
weight, and a BMI of 18.5 to 24.9 constitutes healthy weight.
NOTE: A BMI consistent with overweight (25.0-29.9) does not by itself
indicate that an individual is over-fat, nor does a BMI consistent with
underweight indicate that an individual is not over-fat. There are some instances
where an individual could be misclassified as overweight due to body
composition (e.g., individuals with a large amount of lean muscle tissue, as
might be found in the military). Additional testing must be done to determine
whether the excess weight in such individuals consists of fat.
Overweight and Health
The effects of excess body weight are widespread and raise a variety of
concerns relevant to the health and performance of members of the military. The
major comorbidities associated with obesity and the implications of these co-
morbidities for the military services are briefly reviewed below. (For an exten-
sive review of the major health effects of overweight, see Bray, 1996 and Must
etal., 1999).
Overweight and obesity have also been associated with a variety of adverse
social and economic consequences. These appear to be more significant among
women than among men. For example, one study showed that obese women
completed fewer years of school, married less frequently, and had lower
earnings than women who were not obese (Gortmaker et al., 1993~. Although
these data were obtained before obesity achieved its current prevalence, they
suggest a variety of long-term effects on material and psychological well-being.
Obesity also has a variety of adverse physiological effects. The major
comorbidities associated with obesity are shown in Box 1-1. It has been
observed that the prevalence of type 2 diabetes mellitus, hyperlipidemia,
hypertension, and heart disease increased with the severity of obesity, and that
prevalence ratios were generally greater in younger than in older adults (Must et
al., 1999~. Approximately 70 percent of overweight individuals have at least one
of these complications, and over 30 percent have two or more (Must et al.,
1 999).
Obesity is also associated with increased mortality rates. In one study by
Allison and colleagues (1999), obesity-related mortality was estimated from data
collected in five prospective cohort studies. The estimated number of annual
deaths in the United States attributable to obesity ranged from 280,000 to
OCR for page 19
BACKGROUND AND CONTEXT
19
BOX 1-1 Consequences of Adult Obesity
Psychosocial consequences
Low self-esteem
Disordered eating behavior
. . . .
D'scr~m~nat~on
Medical consequences
Cancer
Diabetes mellitus
Gall bladder disease
Gastro-esophogeal reflux disease
Heart disease
Hyperlipidemia
Hypertension
Osteoarthritis
Polycystic ovary disease
Pscudotumor cerebri
Sleep apnea
Urinary incontinence
Increased maternal and fetal complications during pregnancy and
postpartum
Early mortality
325,000, depending on whether the analysis controlled for smoking rates.
Approximately 80 percent of the deaths attributable to overweight occurred in
persons with a BMI 2 30, which is the lower limit for obesity. The estimates of
the effects of obesity on mortality rates are quite consistent with earlier
published estimates by McGinnis and Foege ( 1993), who suggested that
approximately 300,000 deaths per year could be attributed to poor diet and
inactivity patterns, which are the major contributors to obesity.
The comorbidities associated with obesity substantially increase health care
costs. For example, total costs associated with obesity-related type 2 diabetes
mellitus; coronary heart disease; hypertension; gall bladder diseases; breast,
endometrial, and colon cancer; and osteoarthritis in 2000 were estimated at
almost $117 billion per year (HHS, 2001~. Approximately half of these costs
were medical costs directly associated with the treatment of obesity and its
comorbidities; the other half were indirect costs associated with increased
absenteeism and decreased economic productivity. In one managed care organi-
zation, obesity was clearly associated with increased outpatient visits, inpatient
days, and use of pha~.~acy and radiology services (Quesenberry et al., 1998~.
OCR for page 20
20
WEIGHT A~1NAGEMENT
Upper Body Adiposity
BMI does not account for all of the increased morbidity associated with
obesity; the distribution of adipose tissue also influences the risk of excess
weight. Upper body, or more specifically, visceral adipose tissue, carries a
l~igher morbidity risk than adipose tissue deposited in the subcutaneous compart-
ments of the buttocks, thighs, and lower extremities (NHLBI, 1998~.
Individuals with upper body adiposity may be predisposed to other obesity-
related conditions such as insulin resistance, glucose intolerance, dyslipidemias,
and high blood pressure, often referred to collectively as "Syndrome X" or the
`'metabolic syndrome" (Bjorntorp, 1992a, 1992b; Hjermann, 1992~. Factors that
increase the deposition of visceral adipose tissue include male gender, lack of
physical activity, alcohol use, and smoking (Emery et al., 1993; Han et al.,
19981. The distribution of upper body adipose tissue may also impact appear-
ance, which is relevant to military standards.
In order to clinically evaluate adipose tissue distribution, an individual's
waist circumference (W) is evaluated as a measure of visceral obesity, with W >
l 02 cm (40 in) in men and W > 88 cm (35 in) in women considered high risk for
heart disease (NHLBI, 1998~. Waist circumference measurements are supple-
mentary to BMI when diagnosing overweight and obesity; waist measurements
lose their predictive value for increased risk of heart disease with a BMI 2 35.
UNIQUENESS OF THE MILITARY ENVIRONMENT
Among active duty military personnel, diabetes, hypertension, and ischemic
heart disease accounted for less than 1 percent of visits made to ambulatory care
clinics in 1998. These findings should not be surprising given that active duty
personnel are younger, are less likely to be obese, and are more physically fit
than the average civilian adult. However, overweight and obesity do exist in the
military, and chronic health risk is a concern, especially among older, more
senior personnel. For example, Robbins and coworkers (2002), in a retrospective
cohort study design of active duty Air Force personnel, found that approxi-
mately 20 percent of these men and women exceeded their official maximum
allowable weight-for-height. Based on a review of health records, they estimated
excess weight-attributable medical costs were $19.26 million, with an additional
$3.5 million attributable to lost productivity and 28,351 lost workdays. Although
the primary concern of the Department of Defense (DOD) has been the effects
of weight and body composition on the fitness and performance of military
personnel, recent changes in the laws regarding health care for veterans have
added the costs of obesity-related comorbidity coverage as another area of
concern.
Also of special relevance to the military are the effects of fatness and of the
lack of fitness on injury rates during initial entry training. In several small
OCR for page 21
BACKGROUND AND CONTEXI
21
studies, an increased BMI was associated with an increased injury rate during
initial entry training and with performance in the 1- and 2-mile runs, sit-ups, and
push-ups by men (Jones et al., 19921.
Demographics
There are a number of important demographic differences between the
military and the general population. While the general population is fairly
evenly split between genders (49.1 percent men versus 50.9 percent women)
(U.S. Census Bureau, 2003), the military is largely comprised of men (85
percent versus 15 percent women) (Personal communication, B. Maxfield,
Office of the Deputy Chief of Staff for Personnel, March 7, 2003), although this
varies somewhat with the individual services. For example, the Air Force is
comprised of 80.6 percent men and 19.4 percent women, while the Marine
Corps is comprised of 94 percent men and only 6 percent women (Personal
communication, B. Maxfield, Office of the Deputy Chief of Staff for Personnel,
March 7, 20033.
Ethnic demographics also differ somewhat between the general U.S.
population and the active-duty military population. Although the proportion of
Whites, American Indian/Alaska Natives, and Asian American/Pacific Islanders
in the military tend to reflect the general U.S. population, the percentage of
Black men is higher in the military than in the general population (17.7 percent
vs. 12.3 percent), while the percentage of Hispanic men is lower (9 percent vs.
13.4 percent) (Tables 1-1 and 1-2~. There is also a notable difference in the
distribution of ethnicity by gender in the military compared with the general
population. A greater proportion of women in the military are ethnic minorities.
For example, 41.7 percent of Army women are Black and 9.7 percent are
Hispanic, while 21 percent of Marine Corps women are Black and 16.6 percent
are Hispanic (Table 1-23.
Another significant demographic that differs between the general U.S.
population and the active-duty military population is that of age. While only
31.5 percent of the U.S. population is between the ages of 18 and 40 years (U.S.
Census Bureau, 2003), this age range encompasses nearly 80 percent of the
active-duty military population.
Health and Fitness
Table 1-3 presents a comparison of the percentage of the general population
(Flegal et al., 2002; Freedman et al., 2002) versus the military service population
in four BMI categories. While the percentage of military men and women in the
BMI category of 25 to 29.9 is higher than the general population, the percentage
in the BMI category of > 30 is much lower. Also, the percentage of women with
a BMI of less than 25 is higher for military women than for civilian women. The
OCR for page 22
22
WEIGHT MANAGEMENT
TABLE 1-1 Percent Gender and Race/Ethnicity ofthe U.S. Population
Compared with the Department of Defense (DOD) Population
Gender/Race/Ethnicitya
Men (% of total population)
Race/Ethnicity
White
Black
Hispanic
AA/PI
AI/AN
Women (% of total population)
Race/Ethnicity
White
Black
Hispanic
AAIPI
AI/AN
U.S. Population (%) DOD Population (%)
49.1
68.7
12.3
13.4
4.0
0.9
50.9
69.1
13.1
12.2
3.8
1.2
85
66.4
17.7
9.0
4.0
1.0
15
51.6
31.4
9.2
4.0
1.1
't AA = Asian American, PI = Pacific Islander, AI = American Indian, AN = Alaska
Native.
SOURCE: U.S. data: 2001 U.S. population estimates, U.S. Census Bureau (2003~;
DOD data: 2002 Distribution of Active Duty Forces, Personal communication, B.
Maxfield, Office of the Deputy Chief of Staff for Personnel, March 7, 2003.
high prevalence of military personnel in the 25 to 29.9 BMI category reflects the
fact that until late 2002, the military maximum weight-for-height standards were
not based on the standard BMI categories (NHLBI, 1998~.
The military environment has both positive and negative aspects associated
with it in terms of maintaining physical fitness and healthy weight. On the
positive side, military personnel have ready access to health care providers. In
addition, DOD has the potential for centralized, longitudinal record-keeping on
all active duty personnel, the unusual ability to provide incentives and conse-
quences for weight change, and the potential ability to modify environmental
factors that are important for weight control. Possible negative aspects of the
military environment include a very mobile population and the potential for
inappropriate weight-loss activities fostered by the need to meet weight, fitness,
and fatness standards.
Weight and Body Composition
At present, all active-duty personnel must be weighed and assessed for
physical fitness annually or semiannually. If an individual's weight exceeds the
maximum for his or her height according to the screening tables for his or her
OCR for page 23
BE CKCROUND AND CONTENT
TABLE 1-2 Percent Gender and Race/Ethnicity ofthe Military Branches
23
Military Branch White Black Hispanic AA/PIa AI/ANb Total
Men
Army 61.9 22.1 9.5 3.2 0.8 84.6
Navy 63.3 17.4 9.8 6.5 1.9 85.6
Marine Corps 68.2 13.9 13.1 2.6 0.9 94.0
Air Force 75.4 13.8 5.2 2.9 0.5 80.6
Women
Army 41.2 41.7 9.7 3.8 1.2 15.4
Navy 5 1.6 28.1 1 1.1 5.2 2.8 14.4
Marine Corps 55.6 21.0 16.6 3.2 1.7 6.0
Air Force 61.8 24.7 6.0 3.8 0.7 19.4
" AA = Asian American, PI = Pacific Islander.
" AI = American Indian, AN = Alaska Native.
SOURCE: 2002 Distribution of Active Duty Forces, Personal communication, B. Max-
ileld' Office of the Deputy Chief of Staff for Personnel, March 7, 2003.
service, the individual is referred for a second-tier assessment (a determination
of percent body fat), to ascertain whether the increased weight is due to fat or to
lean tissue. In addition, a commander may order an individual in his or her
command to be weighed at any time if the commander believes that the
individual presents an overweight appearance in uniform. Personnel whose
percent body fat exceeds the limit for their service and who do not qualify for a
medical waiver are referred to a weight-management program (at the discretion
of the commander), which carries professional consequences.
Administration of military weight-management programs is left to each
service individually. These programs, which are described in greater detail in
Chapter 2, generally require a single visit to a health professional followed by
regular weigh-ins until weight and/or body fat goals are reached. Individuals are
required to demonstrate continuing progress toward these goals by losing a
prescribed number of pounds per month. Failure to show continued progress in
weight loss or continued failure to comply with body-fat standards without a
medical waiver can result in separation Tom the service. Similar attention is not
devoted to personnel who are underweight.
Appearance
The DOD appearance standard is articulated by DOD (1995) Directive
1308.1, DOD Physical Fitness and Body Fat Programs. This policy is shared,
but described slightly differently, by each of the service branches. According to
the Directive, "maintaining desirable body composition is an integral part of
OCR for page 24
24
WEIGHT MANAGEMENT
TABLE 1-3 Percent Body Mass Index (BMI) of Military Branchesa by Gender
Compared with the General U.S. Population
Army Navy
BMI Men Women Men Women
-
< 18.5 0.3 0.6 0.5 1.8
18.5-24.9 39.6 58.8 30.4 52.2
25.029.9 46.0 34.4 52.9 38.6
30.0-34.9 13.2 5.6 14.3 6.5
35.~39.9 0.9 0.5 1.7 0.8
>40 <0.1 <0.1 0.2 0.1
No data available for U.S. Marine Corps.
h Adapted Dom Flegal et al. (2002~; Freedman et al. (2002~. BMI categories for U.S.
population data are < 25' 25.0-29.9, 30.~39.9, 2 40.
SOURCE: Army data: Personal communication, G. Bathalon, U.S. Army Medical
physical fitness, general health, and military appearance" (p. 2), and the first line
of body composition evaluation is by weight-for-height and appearance. For
example, according to Army Regulation 600-9 (U.S. Army, 1987), one of the
two goals of military weight standards is for soldiers to present a physical
appearance in uniform "which is neat and trim." The regulation goes on to
describe the standard farther by emphasizing that "excessive body fat connotes a
lack of personal discipline, detracts from military appearance, and may indicate
a poor state of health, physical fitness, or stamina." No objective criteria (rating
scales) have been associated with the appearance standard as it is enforced,
although development of objective criteria has been recommended previously
(IOM, 1992a, 1998~.
Although appearance is associated slightly with percent body fat, it is
associated more significantly with abdominal circumference (Hodgdon et al.,
1990; U.S. Army, 1987; Vogel and Friedl, 1992~. Army and Marine Corps
personnel must supply recent photos of themselves to their promotion boards
(this practice has been eliminated by the Air Force and Navy), but appearance
judgments can be rendered by commanding officers at any time. When these
judgments involve a suspicion of overweight (as opposed to an untidy uniform
or other details of appearance), the individual must be weighed and may be
required to have a body-fat determination and enter a weight-management
program if standards are exceeded. In essence, the Directive considers appear-
ance as important as weight-for-height standards, but it does not provide any
objective criteria for assessing appearance. Instead, the Directive defers
implementation of the policy to the individual services, which in turn defer to
the individual units to establish criteria and implement the policy. This results in
uneven application of the policy among units and across the services.
OCR for page 25
BACKGROUND AND CONTEXT
Air Force
Men Women
U.S. Populationh
Men Women
0.9 3.0
6.7 62.2 32.8 38.1
52.7 3 1.4 39.8 28.5
1 0.5 2.8 26.0 30.6
0.7 0.4 —
<0.1 <0.1 1.5 2.8
Research and Materiel Command, 2003; Navy data: Personal commu-
nication, T. Cepak, Navy Physical Readiness Program, April 25, 2003;
Air Force data: Personal communication, J. Spahn, Population Health
Support Branch, May 15, 2003.
25
The relative role that appearance should play in relation to weight and
body-fat programs in the military is a multifaceted issue. The military embraces
a policy on appearance for several psychosocial reasons:
· It is perceived to be an indication of fitness.
· It may affect how the general public views the military.
· The appearance of military personnel is believed by some to be a factor
in esprit de corps (Bauer et al., 1976; USMC, 1995~.
· It may have some impact on how a country's military is perceived in-
ternationally.
The issue of appearance also influences the individual's self-esteem and accept-
ance by peers.
PREVIOUS RECOMMENDATIONS ON BODY FAT AND FITNESS
In 1992, the Committee on Military Nutrition Research (CMNR) was asked
to evaluate whether the body composition, fitness, and appearance standards of
the military were consistent with optimum job performance. Their report, Body
Composition and Physical Performance: Applications for the Military Services
(IOM, 1 992a), provided five major recommendations:
All the services should develop job-related physical performance tests.
2. The differences between accession and retention standards need
reevaluation for all services.
3. The inequities in the body composition standards for men and women
need to be addressed.
OCR for page 26
26
WEIGHT MANAGEMENT
4. Body composition standards need to be validated relative to the ethnic
diversity of the military population.
5. If the military deems appearance standards necessary (although no
relationship between military appearance and military performance could be
identified), these standards should be objective.
Following the lifting of the combat exclusion rule in 1993 (which opened to
women a large number of occupational specialties that were previously closed to
them) and the increased frequency of deployments, the percentage of female
active-duty personnel has steadily increased. Concerned that the body compo-
sition, appearance, and fitness policies might be negatively impacting the health
of female service personnel, the U.S. Army Medical Research and Materiel
Command (USAMRMC) requested that CMNR revisit these issues specifically
tic then nertainer1 tn military women. In response to this request, the CMNR
~ A r-~ A,
Subcommittee on Body Composition, Nutrition, and Health of Military Women
published a report (TOM, 19981. This report examined the body composition and
fitness standards of the four service branches in light of recent research that
explored the relationships among body composition, fitness, performance,
nutrition status, and health. To assess the implications of meeting the body
composition and appearance standards for women, military weight-management
programs and dieting practices were examined and compared with those in the
civilian sector. The report also explored the potential health risks of chronic
dieting in light of the high performance level expected of military personnel
since underweight may be as much of a medical concern as overweight. This
review (IOM, 1998) provided several key recommendations for military women:
.
BMI and fitness assessment should be incorporated into the current
two-tiered system of body composition assessment procedures.
. The maximum allowable BMI should be set at 25, based on considera-
tions of health and chronic disease risk, with a maximum body fat of 36 percent
for women if the fitness test is passed.
.
A single, service-wide circumference equation should be developed and
validated for the assessment of women's body fat.
.
Military women should be strongly encouraged to achieve and maintain
healthy weights through a continuous exercise and fitness program and should
be provided nutrition education and ongoing counseling if weight loss is a goal.
THE CURRENT TASK
In July 1999, CMNR was requested to (1) review the data on optimal
components of a weight-management program, (2) review the data on the role of
age, gender, and ethnicity in weight management, (3) review current DOD
activities in weight management, and (4) provide recommendations for military
OCR for page 27
BACKGROUND AND CONTEXT
27
weight-management programs. This request originated from the Director of
Military Operational Medicine Research at USAMRMC. The Subcommittee on
Military Weight Management was appointed in September 1999; on October
24-27, 1999, the committee convened a workshop in response to a request from
Army representatives. The workshop brought together the personnel responsible
for both DOD-wide and service-specific weight-control program policies; a
representation of military weight-control program leaders and innovators; and
key military, academic, and industry researchers to:
.
Share knowledge and experience in managing weight-control programs
within the services.
Gain relevant knowledge and experience from industry and academia.
Examine current interventions and those under development for weight
loss, particularly in the pharmaceutical industry.
.
Evaluate the appropriateness of weight-loss interventions for military
application or the need for further research.
.
Develop a consensus toward a more standard DOD-wide approach to
weight management that utilizes state-of-the-art knowledge and practices.
The subcomr~ttee was charged to identify the most effective interventions
for weight loss and maintenance, particularly those most effective for the non-
obese overweight individuals found in the military setting. Specifically, this
subcommittee was asked to addresses the following questions:
1. What are the essential components of an effective weight/fat-loss pro-
gram, and the most effective strategies for sustaining weight loss?
2. How do age and gender influence success in weight-management pro-
grams? Should age be considered in weight/fat standards and in weight-
management programs and interventions?
3. Which strategies would be the most and least effective in a military set-
ting? Should military weight/fat loss programs involve direct participation inter-
ventions or only monitoring and guidance? Should military programs be more
proactive in identifying and discouraging ineffective or dangerous weight-loss
practices? Is a warning or cautionary zone prior to enrollment into a weight-
control program an effective strategy? When should duty time be authorized for
participation in intervention strategies for weight/fat loss?
4. To what extent should weight-control programs/policies be standard-
ized across the services versus tailored to the individual service, installation, or
unit? What are the advantages and disadvantages of standardization? Is the pro-
vision of state-of-the-art techniques and knowledge a rationale for standardiza-
tion?
5. How can diet be effectively dealt with as a weight-management com-
ponent in the military setting? Should pharmacological treatment (anorexiants)
J
OCR for page 28
28
WEIGHT MANAGEMENT
be considered for use in the military? In what cases? What factors bear on this
decision?
6. How should resistiveness to weight/fat control be dealt with?
7. What are the knowledge gaps in weight-management programs relative
to the military? What research is needed?
SUMMARY
The rise in prevalence of overweight and obesity in the general population
as defined by specific BMI cut-off of > 25 for overweight and > 30 for obesity
has been associated with a significant increase in chronic diseases and mortality.
However, among active-duty military personnel, 80 percent of whom are be-
tween 18 and 40 years of age, chronic obesity-related diseases are less of an
issue than the impact of overweight on physical fitness, performance of jobs that
require physical exertion, injury rates, and appearance.
Representative terms from entire chapter:
active duty
