Eating patterns and leisure-time exercise among active duty military personnel: comparison to the Healthy People objectives.

OBJECTIVE: To assess whether active duty military personnel meet Healthy People 2010 objectives for physical activity and fruit, vegetable, and whole-grain intake; the relationship of select demographic characteristics, lifestyle factors (eg, smoking), and eating patterns (eg, frequency and location of meals) on achieving diet and exercise-related Healthy People 2010 objectives; and the relationship of eating patterns to self-reported weight gain. METHODS: Secondary data from 15,747 participants in the 2005 Department of Defense Health Related Behaviors Survey was analyzed. RESULTS: More than 57% of respondents met the Healthy People 2010 guidelines for moderate or vigorous leisure exercise but only 3% reported eating fruit (once), vegetables (3 times), and whole grains (3 times) daily. Individuals who reported gaining weight during the previous year were more likely to skip breakfast and eat at, or from, a restaurant ≥2 times per week compared with those who did not gain weight (P<0.001). Regression analysis indicated that women were more likely to eat fruits (odds ratio [OR] 1.25) and vegetables (OR 1.20) and less likely than men to eat whole grains (OR 0.76) or engage in moderate or vigorous exercise (OR 0.71). Military personnel who skipped breakfast ≥2 times per week (OR 0.45) or ate at a restaurant/takeout food (OR 0.54) ≥2 times per week were significantly less likely to meet Healthy People 2010 guidelines for food intake (defined as achieving a daily intake of one or more fruits, three or more vegetables, and three or more servings of whole grains) and exercise (OR 0.88 and 0.82, respectively). CONCLUSIONS: Although the majority of military personnel met guidelines for physical activity, their intake of fruits, vegetables, and whole grains was suboptimal. Skipping breakfast and eating at, or from, restaurants were risk factors for poor nutrient intake and associated with weight gain. These data suggest that skipping breakfast and eating out deter achieving Healthy People 2010 objectives and provide targets for military programs to promote achieving these objectives.

Efficacy of orlistat 60 mg on weight loss and body fat mass in US Army soldiers.

A higher body mass index is associated with exercise-related injuries and increased risk for musculoskeletal and connective tissue disorders, which are relevant to military personnel. Studies show the efficacy of orlistat 60 mg for promoting weight and body fat loss in civilians; however, its efficacy among predominantly young, male soldiers is unknown. This study's objective was to examine the effect of a 6-month, standard education-based weight-management program with and without orlistat 60 mg on changes in weight and body fat in overweight soldiers. Data were collected for this randomized, controlled trial from March 2008 to November 2010 at Fort Bragg, NC. Participants were enrolled in an education-based weight management program (n=435; 75% men) and were randomized to placebo or orlistat 60 mg, three capsules daily with meals. All participants were recommended to maintain a reduced-energy, low-fat diet. Among study completers (14% retention rate; placebo n=22, orlistat n=35) members of both groups lost significant weight from baseline (placebo -3.0±5.2 kg; orlistat -3.2±4.7 kg; P<0.01), but only the orlistat group lost fat mass (-2.5±3.9 kg; P<0.001), whereas the placebo group lost lean mass (-1.4±2.7 kg; P <0.01). An intent-to-treat analysis (?1 follow-up body weight measure) demonstrated that the orlistat group lost more fat mass vs the placebo group (-1.3±2.9 kg vs ?0.6±1.8 kg, respectively; P<0.05), but less lean mass (-0.2±2.0 kg vs -0.8±1.8 kg, respectively; P<0.01). Orlistat 60 mg may be an effective adjunct to an education-based weight management program in a mostly young, male soldier population.

Overweight and obesity in military personnel: sociodemographic predictors.

In the United States, nationally representative civilian studies have shown that BMI is associated with select sociodemographic characteristics. Active-duty military personnel are not included in these surveys and the persistence of these associations in military personnel is unknown. Data from the worldwide, representative 2002 and 2005 Department of Defense (DoD) Surveys of Health-Related Behaviors Among Active Duty Military Personnel were used to assess the prevalence of overweight and obesity and, the association of BMI with sociodemographic characteristics. The final response bases included 12,756 (2002) and 16,146 (2005) personnel. Results indicated that the combined prevalence of overweight and obesity in military personnel increased to an all-time high in 2005 (60.5%) with higher prevalence of obesity in 2005 compared to 2002 (12.9% vs. 8.7, respectively, P ≤ 0.01). Holding other variables constant, regression analysis indicated that women were significantly less likely than men to be overweight or obese in both survey years (P ≤ 0.0001), which is contrary to civilian data. Similar to civilian data, the prevalence of obesity was significantly associated with increased age, black or Hispanic/Latino race/ethnicity, and being married (P ≤ 0.01). US military personnel are not immune to the US obesity epidemic. Demographic characteristics associated with being overweight should be considered when developing military-sponsored weight management programs.

Female anthropometric variability and their effects on predicted thermoregulatory responses to work in the heat.

The use of thermoregulatory models for assessing physiological responses of workers in thermally stressful situations has been increasing because of the risks and costs related to human studies. In a previous study (Yokota et al. Eur J Appl Physiol 104:297-302, 2008), the effects of anthropometric variability on predicted physiological responses to heat stress in U.S. Army male soldiers were evaluated. Five somatotypes were identified in U.S. Army male multivariate anthropometric distribution. The simulated heat responses, using a thermoregulatory model, were different between somatotypes. The present study further extends this line of research to female soldiers. Anthropometric somatotypes were identified using multivariate analysis [height, weight, percent body fat (%BF)] and the predicted physiological responses to simulated exercise and heat stress using a thermoregulatory model were evaluated. The simulated conditions included walking at ~3 mph (4.8 km/h) for 300 min and wearing battle dress uniform and body armor in a 30°C, 25% relative humidity (RH) environment without solar radiation. Five major somatotypes (tall-fat, tall-lean, average, short-lean, and short-fat), identified through multivariate analysis of anthropometric distributions, showed different tolerance levels to simulated heat stress: lean women were predicted to maintain their core temperatures (T(c)) lower than short-fat or tall-fat women. The measured T(c) of female subjects obtained from two heat studies (data1: 30°C, 32% RH, protective garments, ~225 w·m(-2) walk for 90 min; data2: 32°C, 75% RH, hot weather battle dress uniform, ~378 ± 32 w·m(-2) for 30 min walk/30 min rest cycles for 120 min) were utilized for validation. Validation results agreed with the findings in this study: fat subjects tended to have higher core temperatures than medium individuals (data2) and lean subjects maintained lower core temperatures than medium subjects (data1).

Lipid and other plasma markers are associated with anxiety, depression, and fatigue.

OBJECTIVE: Few peripheral metabolites have been shown to be associated with mood in healthy individuals or patients with central nervous system diseases. During military basic combat training (BCT), mood state, physical performance and body composition substantially improve, providing an opportunity to examine relationships between mood and nutritional and hormonal biomarkers. METHOD: Thirty-five females enrolled in U.S. Marine BCT, an intense physically and mentally challenging 12-week course, were studied. Every 4 weeks, mood was assessed with the Profile of Mood States (POMS), as were nutritional, metabolic and hormonal plasma markers. RESULTS: Mood and fitness improved over BCT, and there were substantial changes in biochemical markers. Multiple regression demonstrated that, in combination, cholesterol (HDL, LDL), fructosamine, triglycerides, free fatty acids (FFA), dehydroepiandrosterone-sulfate (DHEA-S), ACTH, and substance P accounted for 44% of variation in anxiety, 40% confusion, 37% fatigue, 27% depression and 40% in total mood (p < .0001). Increased HDL, FFA, DHEA-S, and substance P were associated with degraded mood (p < .05). Increased LDL, triglycerides, fructosamine, and ACTH were associated with improved mood (p < .05). Other markers, including glucose, cortisol, and C-reactive protein were not associated with mood. CONCLUSIONS: Normal human mood state was associated with 8 plasma markers. Increased HDL and lower LDL, which are associated with improved cardiovascular status, were associated with negative affect. Fructosamine and substance P, not previously known to be related to mood, were associated with it. We are not aware of any biological parameters that in aggregate predict such a substantial proportion of variation in normal mood.

Efficacy of a meal-replacement program for promoting blood lipid changes and weight and body fat loss in US Army soldiers.

Excess weight is associated with negative health outcomes. Meal replacements are effective in promoting favorable body composition changes in civilian populations; however, their efficacy with military service members who have unique lifestyles is unknown. The objective of this randomized controlled trial was to determine the efficacy of the Army's education-based weight-management program, "Weigh to Stay," with and without meal replacements for improving blood lipids, and to promote weight and body fat loss in overweight US Army soldiers. Soldiers (n=113; 76 males/37 females) attending Weigh to Stay at Fort Bragg, NC, in 2006/2007 were randomized to Weigh to Stay only or a commercially available meal-replacement program (two meal replacements per day) in conjunction with Weigh to Stay, and followed until Army body fat standards were met or for 6 months if standards were not met. Study completers (n=46) in both treatment groups lost weight (Weigh to Stay: -2.7+/-4.3 kg; meal replacers: -3.8+/-3.5 kg) and fat mass (Weigh to Stay, -2.7+/-3.2 kg; meal replacers: -2.9+/-2.5 kg), and improved high-density lipoprotein cholesterol concentrations (Weigh to Stay: 13+/-9 mg/dL [0.34+/-0.23 mmol/L]; meal replacers: 8+/-7 mg/dL [0.21+/-0.18 mmol/L]; P<0.05); however, no between-group differences were observed. Attrition was lower (P=0.009) and success in meeting body fat standards tended to be higher (P=0.06) for the meal replacers vs Weigh to Stay participants. Intent-to-treat analysis demonstrated that meal replacers lost more weight (1.2+/-0.5 kg), percent body fat (1.0%+/-0.4%), and fat mass (0.8+/-0.4 kg) compared to Weigh to Stay volunteers (P<0.05). Our findings suggest that meal replacement use can be recommended as a potential adjunct strategy to Weigh to Stay.

Monitoring energy intake: a hand-held personal digital assistant provides accuracy comparable to written records.

New approaches to assess energy intake (EI) may have advantages over traditional written methods, but validity of these emerging methodologies must be demonstrated. This exploratory study compared EI obtained using a hand-held personal digital assistant (PDA) and traditional written records with total energy expenditure measured by doubly labeled water (TEE(DLW)). Twenty-six volunteers (aged 23+/-4 years, body mass index [calculated as kg/m(2)] 24+/-2) participated in a randomized (either PDA or written record group) and matched (for sex, age, and body mass index) study for 7 consecutive days between June 2005 and April 2006 to record EI. Group comparisons were made with t and Mann-Whitney U tests. Bland-Altman plots were used to compare limits of agreement between methods. Volunteers remained weight stable during the study period (0.2+/-0.8 kg; P>0.05). Reported EI by written record and PDA were similar to TEE(DLW); 105% vs 92% of TEE(DLW), respectively (P>0.05). There was a significant relationship between reported EI by PDA and TEE(DLW) (r=0.60, P<0.05), but not for written record (r=0.45, P>0.05). Limits of agreement indicated both written record and PDA had large variability (range 1,394 to -1,472 kcal/day). Findings suggest the bias in using a PDA is similar to that observed when using a written record for estimation of EI in weight-stable volunteers.

Military services fitness database: development of a computerized physical fitness and weight management database for the U.S. Army.

The Department of Defense (DoD) has mandated development of a system to collect and manage data on the weight, percent body fat (%BF), and fitness of all military personnel. This project aimed to (1) develop a computerized weight and fitness database to track individuals and Army units over time allowing cross-sectional and longitudinal evaluations and (2) test the computerized system for feasibility and integrity of data collection over several years of usage. The computer application, the Military Services Fitness Database (MSFD), was designed for (1) storage and tracking of data related to height, weight, %BF for the Army Weight Control Program (AWCP) and Army Physical Fitness Test (APFT) scores and (2) generation of reports using these data. A 2.5-year pilot test of the MSFD indicated that it monitors population and individual trends of changing body weight, %BF, and fitness in a military population.

Disordered eating and weight changes after deployment: longitudinal assessment of a large US military cohort.

The effect of military deployments to combat environments on disordered eating and weight changes is unknown. Using longitudinal data from Millennium Cohort Study participants who completed baseline (2001-2003) and follow-up (2004-2006) questionnaires (n=48,378), the authors investigated new-onset disordered eating and weight changes in a large military cohort. Multivariable logistic regression was used to compare these outcomes among those who deployed and reported combat exposures, those who deployed but did not report combat exposures, and those who did not deploy in support of the wars in Iraq and Afghanistan. Deployment was not significantly associated with new-onset disordered eating in women or men, after adjustment for baseline demographic, military, and behavioral characteristics. However, in subgroup comparison analyses of deployers, deployed women reporting combat exposures were 1.78 times more likely to report new-onset disordered eating (95% confidence interval: 1.02, 3.11) and 2.35 times more likely to lose 10% or more of their body weight compared with women who deployed but did not report combat exposures (95% confidence interval: 1.17, 4.70). Despite no significant overall association between deployment and disordered eating and weight changes, deployed women reporting combat exposures represent a subgroup at higher risk for developing eating problems and weight loss.

Female marine recruit training: mood, body composition, and biochemical changes.

PURPOSE: The US Marine Corps (USMC) is an elite military organization. Marine recruit training (RT) is a physically and psychologically intense 13-wk-long course designed to transform civilians into Marines through shared hardship and arduous training. Our laboratory conducted a study of female recruits in USMC RT that assessed the nature and the extent of cognitive, nutritional, and physical changes that occur during this unique period of structured mental and physical training. METHODS: During RT, mood state was assessed every 4 wk with a standardized questionnaire, the POMS. Body composition was assessed with dual-energy x-ray absorptiometry every 4 wk, and blood samples were collected for assessing metabolic status at the start and at the completion of training. RESULTS: At the beginning of RT, approximately 1 wk after arrival at the training facility, levels of several negative mood states assessed by the POMS, depression, anxiety, fatigue, anger, and confusion, were considerably higher than POMS norms for age-matched, female college students. However, over the course of RT, these mood states gradually declined until, by the completion of training, they were substantially lower than college norms. Body composition changed dramatically, with muscle mass increasing by 2.5 +/- 0.2 kg on average and fat declining by 4.7 +/- 0.4 kg. There were also significant changes in several biochemical parameters associated with nutritional and physical status, particularly LDL cholesterol, free fatty acids, and cortisol. Other factors, such as total cholesterol, HDL cholesterol, and glucose, were more stable. CONCLUSIONS: Over the course of USMC RT, mood and body composition improved substantially and dramatically, an indication of the effectiveness of USMC RT for altering the physical and the cognitive status of trainees.

Assessment of male anthropometric trends and the effects on simulated heat stress responses.

Assessing temporal changes in anthropometrics and body composition of US Army soldiers is important because these changes may affect fitness, performance, and safety. This study investigated differences in body dimensions (height, weight, percent body fat (%BF)) of US Army male soldiers by comparing 2004 and 1988 databases. Anthropometric somatotypes were identified and physiological responses of the different somatotypes to simulated heat stress (35 degrees C/50%rh, approximately 550 W work rate, carrying 12 kg load including battle dress uniform and body armor, rest for 30 min and walk for 70 min) using a thermal regulatory model were evaluated. A significant increase in body weight (2.4 kg) was observed between the 2004 and 1988 data (P < 0.05, after Bonferroni correction). However, changes in height and circumference measurements for %BF were insignificant, with the magnitude of the changes not exceeding inter-observer errors. Multivariate analyses demonstrated that anthropometric distributions did not differ between the two databases and identified five primary somatotypes: "tall-fat", "tall-lean", "average", "short-lean", and "short-fat." Within each database, anthropometric values differed among the somatotypes. However, simulated physiological responses to heat stress in each somatotype were similar in the 2004 and 1988 populations. In conclusion, an increase in body weight was the primary change observed in this sample of US Army male soldiers. Temporal changes in somatotypes of soldiers over a 16-year period had minimal impact on simulated physiological response to heat stress using a thermal regulatory model.

The effect of proposed improvements to the Army Weight Control Program on female soldiers.

OBJECTIVE: To comply with Army Regulation 600-9, The Army Weight Control Program (AWCP), soldiers must meet age-adjusted body fat standards, regardless of whether they meet or exceed weight-for-height allowances. Recent revisions to Department of Defense (DoD) policies require changes to the AWCP. Specifically, we assessed the effects of increasing weight-for-height allowances and adoption of the DoD body fat equation on compliance with the AWCP in women. METHODS: Weight, height, circumferences (neck, forearm, wrist, waist, and hip) to measure body fat, and Army Physical Fitness Test results were obtained from 909 female soldiers (mean (SD) age, 26.2 (6.5) years; body mass index, 24.6 (3.3) kg/m2; body fat, 29.7% (5.0)). RESULTS: Increasing the screening weight-for-height allowances resulted in a 20% reduction in those requiring a body fat measurement (from 55% [n = 498) to 35% [n = 319]). Adopting the DoD body fat equation did not change the proportion of overfat women, i.e., noncompliant with the AWCP, (from 26% [n = 232] to 27% [n = 246]). More women with a waist circumference > 35 inches (i.e., at increased disease risk) were identified as noncompliant with the AWCP by the proposed body fat equation (from 76% [n = 61] to 96% [n = 77]). CONCLUSIONS: Proposed changes reduce the proportion of women unnecessarily measured for body fat and do not change the proportion of women on the AWCP, yet select more women at increased disease risk and most in need of an effective intervention.

Eating behavior and weight change in healthy postmenopausal women: results of a 4-year longitudinal study.

BACKGROUND: The association of psychological eating behavior constructs with overweight and obesity during early adult life and middle age has been documented in several studies. However, the association of eating behavior with unexplained weight change in old age is relatively unexplored. METHODS: Body weight, eating behavior (dietary restraint, disinhibition, and hunger as assessed by the Eating Inventory), reported dietary intake, and physical activity level were assessed at baseline in 36 nonobese postmenopausal women aged 61.3 +/- 3.1 years (mean +/- standard deviation). Measurements were repeated 4.4 +/- 0.9 years later, and changes in body weight were examined in relation to baseline and follow-up eating behavior scores, reported dietary intake, and physical activity level. RESULTS: Participants had no major changes in health or lifestyle characteristics over the study interval. Weight change ranged from -7.5 to +5.8 kg (mean -0.3 +/- 3.5 kg), and there were no significant changes in reported dietary intake. Mean hunger score (calculated as the mean of baseline and follow-up hunger score) predicted weight change per year over the study period (bivariate r = 0.386, p =.020), even in statistical models adjusted for mean dietary intake variables (partial r = 0.658, p =.003). Restraint, disinhibition, and physical activity level did not predict weight change. CONCLUSIONS: Reported hunger assessed by the Eating Inventory was associated with unintentional weight change in healthy postmenopausal women. The Eating Inventory questionnaire may provide a clinically useful tool for identifying older individuals at risk of undesirable weight change, and particularly unintentional weight loss, a factor strongly associated with increased morbidity and premature death in this population.

The fog of war: decrements in cognitive performance and mood associated with combat-like stress.

INTRODUCTION: Anecdotal reports from military conflicts suggest cognitive performance and mood are severely degraded by the stress of combat. However, little objective information is available to confirm these observations. METHODS: Our laboratory had several unique opportunities to study cognitive function in warfighters engaged in exercises designed to simulate the stress of combat. These studies were conducted in different environments with two different types of military volunteers. In one study, subjects were officers, with an average 9 yr of military service, who were members of an elite U.S. Army unit, the Rangers. In the other study, participants were younger, mostly enlisted, trainees with only 3 yr of military experience on average, in training to determine if they would qualify for an elite U.S. Navy unit, the SEALS. We administered a variety of identical, computer-based cognitive tests to both groups. RESULTS: In both groups, during stressful combat-like training, every aspect of cognitive function assessed was severely degraded compared with baseline, pre-stress performance. Relatively simple cognitive functions such as reaction time and vigilance were significantly impaired, as were more complex functions, including memory and logical reasoning. DISCUSSION: The deficits observed were greater than those typically produced by alcohol intoxication, treatment with sedating drugs, or clinical hypoglycemia. Undoubtedly, such decrements would severely degrade operational effectiveness. Furthermore, it is likely such cognitive decrements would be greater during actual combat. War planners, doctrine developers, and warfighters, especially leaders, need to be aware that combat stress will result in extensive and severe deficits in cognitive performance.

Severe decrements in cognition function and mood induced by sleep loss, heat, dehydration, and undernutrition during simulated combat.

BACKGROUND: Military exercises generate high levels of stress to simulate combat, providing a unique opportunity to examine cognitive and physiologic responses of normal humans to acute stress. METHODS: Cognitive and physiologic markers of stress were evaluated before, during, and after an intense training exercise conducted for 53 hours in the heat. Cognitive performance, mood, physical activity, sleep, body composition, hydration, and saliva cortisol, testosterone, and melatonin were assessed. Volunteers were 31 male U.S. Army officers from an elite unit, aged 31.6 +/- .4 years. RESULTS: Wrist activity monitors documented that soldiers slept only 3.0 +/- .3 hours during the exercise and were active throughout. Volunteers lost 4.1 +/- .2 kg (p < .001) of weight, predominately water (3.1 +/- .3 L) (p < .001). Substantial degradation in cognitive function, assessed with computerized tests, occurred. Vigilance, reaction time, attention, memory, and reasoning were impaired (p < .001). Mood, including vigor (p < .001), fatigue (p < .001), confusion (p < .001), depression (p < .001), and tension (p < .002), assessed by questionnaire, deteriorated. The highest cortisol and testosterone levels were observed before the exercise. CONCLUSIONS: This study quantifies the overwhelmingly adverse impact of multiple stressors on cognitive performance, mood, and physiologic parameters, during a continuous but brief military exercise conducted by highly motivated, well-trained officers.

Eating behavior correlates of adult weight gain and obesity in healthy women aged 55-65 y.

BACKGROUND: The specific underlying causes of adult weight gain remain uncertain. OBJECTIVE: The objective was to determine the association of 3 measures of eating behavior with weight gain and body mass index (BMI; in kg/m(2)) in adults. DESIGN: Current dietary restraint, disinhibition, and hunger were assessed with the use of the Eating Inventory in 638 healthy, nonsmoking women aged 55-65 y. In addition, subjects reported their current weight and height, their weight for 6 age intervals, and changes in voluntary dietary energy restriction over the past 10 y. Current weight and height were validated in 10% of subjects. RESULTS: Current disinhibition strongly predicted weight gain and current BMI (partial r = 0.27 and 0.34, respectively, both P < 0.001). Neither restraint nor hunger was a significant independent predictor of either variable, but the positive associations between disinhibition and both weight gain and BMI were attenuated by restraint (P = 0.016 and 0.010, respectively, after adjustment for confounding variables). In the subpopulation of women who reported a stable level of voluntary dietary energy restriction, disinhibition also strongly predicted weight gain and higher BMI, and restraint was negatively associated with weight gain (partial r = -0.17, P = 0.019). CONCLUSIONS: Higher disinhibition is strongly associated with greater adult weight gain and higher current BMI, and dietary restraint may attenuate this association when disinhibition is high. These findings suggest that eating behavior has an important role in the prevention of adult-onset obesity and that further studies are warranted.

The association of eating behavior with risk for morbidity in older women.

BACKGROUND: Although an influence of eating behavior on dietary intake and physiology has been documented in several studies, the extent to which eating behavior influences long-term health is uncertain. METHODS: Current dietary restraint, disinhibition, and hunger were assessed using the Eating Inventory in 1252 nonsmoking women aged 55 to 65 years. In addition, subjects reported the presence or absence of 22 specific morbidities, along with general demographic information. Logistic regression was used to examine associations between eating behavior scores and morbidity, adjusting for age, prior smoking status, hormone replacement therapy, education level, and body mass index (BMI). RESULTS: In adjusted models excluding BMI, higher disinhibition scores were associated with small increased risks for hypercholesterolemia (odds ratio [OR] 1.04, p =.045), leg cramps (OR 1.05, p =.044), indigestion (OR 1.06, p =.020), and cataract (OR 1.09, p =.036), and a decreased risk of eczema (OR 0.91, p =.008). In addition, higher hunger scores were associated with increased risk of eczema (OR 1.09, p =.026). However, after adjusting for confounding variables plus BMI, higher disinhibition scores were associated with increased risks for low back pain (OR 1.06, p =.031) and constipation (OR 1.10, p =.004), and associations of disinhibition and hunger with eczema were unchanged (OR 0.90, p =.008 and OR 1.09, p =.024, respectively). Dietary restraint was not associated with morbidity in any model. CONCLUSIONS: Higher disinhibition and hunger scores were associated with small alterations in reported morbidity risk in a large population of nonsmoking older women. Although our cross-sectional study design makes the directionality of these relationships unclear, our results suggest at most a relatively minor independent influence of eating behavior constructs on long-term health.

Metabolic aging and predicted longevity: results of a cross-sectional study in post-menopausal women.

BACKGROUND AND AIMS: The extent to which general characteristics of metabolic aging contribute to differences in life span among individuals remains uncertain. The objective of this study was to examine the association of age-related physiological and metabolic variables with predicted longevity in postmenopausal women. METHODS: Subjects were 33 healthy women aged 55-65 years. Total and resting energy expenditure, body temperature, immune function as assessed by a delayed-type hypersensitivity skin test (DTH), lipid profile, and reported dietary intake were measured. RESULTS: There were no significant associations between longevity, energy expenditure, body temperature, lipid profile, or dietary intake. However, there was a significant association of predicted longevity with DTH (partial r=0.44, p=0.023). CONCLUSIONS: These results suggest that immune function may predict familial differences in longevity, while energy expenditure, body temperature, lipid profile, and dietary intake are unrelated. Although the small sample size may have limited the ability to detect metabolic effects on longevity in this study, the general approach may be broadly applicable to examinations of metabolic aging in humans.