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In the Men's Lifestyle Validation Study (2011–2013), we examined the validity and relative validity of a physical activity questionnaire (PAQ), a Web-based 24-hour recall (Activities Completed Over Time in 24 Hours (ACT24)), and an accelerometer by multiple comparison methods. Over the course of 1 year, 609 men completed 2 PAQs, two 7-day accelerometer measurements, at least 1 doubly labeled water (DLW) physical activity level (PAL) measurement (n  = 100 with repeat measurements), and 4 ACT24s; they also measured their resting pulse rate. A subset (n  = 197) underwent dual-energy x-ray absorptiometry (n  = 99 with repeated measurements). The method of triads was used to estimate correlations with true activity using DLW PAL, accelerometry, and the PAQ or ACT24 as alternative comparison measures. Estimated correlations of the PAQ with true activity were 0.60 (95% confidence interval (95% CI): 0.52, 0.68) for total activity, 0.69 (95% CI: 0.61, 0.79) for moderate-to-vigorous physical activity (MVPA), and 0.76 (95% CI: 0.62, 0.93) for vigorous activity. Corresponding correlations for total activity were 0.53 (95% CI: 0.45, 0.63) for the average of 4 ACT24s and 0.68 (95% CI: 0.61, 0.75) for accelerometry. Total activity and MVPA measured by PAQ, ACT24, and accelerometry were all significantly correlated with body fat percentage and resting pulse rate, which are physiological indicators of physical activity. Using a combination of comparison methods, we found the PAQ and accelerometry to have moderate validity for assessing physical activity, especially MVPA, in epidemiologic studies. [ABSTRACT FROM AUTHOR]

Caloric restriction (CR) is a strategy that attenuates aging in multiple nonhuman species. The Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE) trials are part of a research program aiming to test the effects of CR on aging and longevity biomarkers in humans. Building on CALERIE phase 1, CALERIE phase 2 (CALERIE 2) was the largest study to date to assess sustained CR in healthy humans without obesity. In a 24-month randomized controlled trial comprising 218 participants at baseline, CALERIE 2 showed that moderate CR, 11.9% on average, induced improvements in aging-related biomarkers without adversely affecting psychological or behavioral outcomes. The objectives of this report are to summarize and review the highlights of CALERIE 2 and report previously unpublished results on eating disorder symptoms and cognitive function. This article specifically summarizes the physiological, psychological, aging, behavioral, and safety results of the trial. Also provided are research directions beyond CALERIE 2 that highlight important opportunities to investigate the role of CR in aging, longevity, and health span in humans. [ABSTRACT FROM AUTHOR]

Adult civilian dependents of active duty military personnel (ADMP) may play a central role in influencing the home food environment and the risk of overweight and obesity in American Warfighters and military families. However, there is no information on whether this group would be receptive to weight control programs. We conducted a survey to determine the level of interest of adult civilian dependents of ADMP in participating in a group weight control program. Subjects were a convenience sample of 191 adult civilian dependents of ADMP (94% women, 6% men) based in Massachusetts and aged 33.8 ± 8.4 years, body mass index 25.5 ± 5.5 kg/m(2). Overall, there was a significant effect of body mass index on interest in program participation (p = 0.004). Eighty five percent of overweight participants and 100% of obese participants reported being Moderately Likely or Very Likely to participate in a provided weight control program. In overweight and obese survey respondents there was no significant effect of ADMP rank on interest in program participation (p = 0.34). These findings suggest that overweight and obese adult civilian dependents of ADMP may be very receptive targets for programs to control overweight and obesity in military families. [ABSTRACT FROM AUTHOR]

Background. In a robust and consistent manner, sustained caloric restriction (CR) has been shown to retard the aging process in a variety of animal species. Nonhuman primate studies suggest that CR may have similar effects in longer-lived species. The CALERIE (Comprehensive Assessment of the Long-term Effects of Reducing Intake of Energy) research program is the first systematic investigation of CR in nonobese human beings. In the phase 2 study, it is hypothesized that 2 years of sustained CR, involving a 25% reduction of ad libitum energy intake, results in beneficial effects similar to those observed in animal studies. This article presents the design and implementation of this study. Methods. The study is a multicenter, parallel-group, randomized controlled trial. A sample of 225 participants (22.0 ≤ body mass index [BMI] < 28.0 kg/m2) is being enrolled with 2:1 allocation to CR. Results. An intensive dietary and behavioral intervention was developed to achieve 25% CR and sustain it over the 2 years. Adherence is monitored using a doubly labeled water technique. Primary outcomes are resting metabolic rate and core temperature, and are assessed at baseline and at 6-month intervals. Secondary outcomes address oxyradical formation, cardiovascular risk markers, insulin sensitivity and secretion, immune function, neuroendocrine function, quality of life and cognitive function. Biologic materials are stored in a central repository. Conclusions. An intricate protocol has been developed to conduct this study. Procedures have been implemented to safeguard the integrity of the data and the conclusions drawn. The results will provide insight into the detrimental changes associated with the human aging process and how CR mitigates these effects. [ABSTRACT FROM PUBLISHER]

Calorie restriction (CR) enhances immune response and prolongs life span in animals. However, information on the applicability of these results to humans is limited. T-cell function declines with age. We examined effects of CR on T-cell function in humans. Forty-six overweight, nonobese participants aged 20-42 years were randomly assigned to 30% or 10% CR group for 6 months. Delayed-type hypersensitivity (DTH), T-cell proliferation (TP), and prostaglandin E(2) (PGE(2)) productions were determined before and after CR. DTH and TP to T-cell mitogens were increased in both groups over baseline (p < or = .019). However, number of positive responses to DTH antigens (p = .016) and TP to anti-CD3 reached statistical significance only after 30% CR (p = .001). Lipopolysaccharide-stimulated PGE(2) was reduced in both groups but reached statistical significance after 30% CR (p < or = .029). These results, for the first time, show that 6-month CR in humans improves T-cell function. [ABSTRACT FROM AUTHOR]

Exercise has well-recognized health benefits, including reduction in risk factors for cardiovascular disease and type 2 diabetes. However, the extent to which exercise influences energy regulation and facilitates a reduction in body fat is less clear. This review summarizes published studies on the effects of different amounts of exercise on body fatness, energy intake, and food preferences in humans. The results show consistent effects of exercise on body fatness in the absence of prescribed dietary change, with a progressive loss of body fat associated with higher exercise energy expenditures in both men and women. In part, these effects appear to be mediated by a spontaneous reduction in hunger associated with participation in exercise. Insufficient data are available on whether there are changes in food preferences and taste perception that influence energy balance through macronutrient selection, so further studies in this area are needed. [ABSTRACT FROM AUTHOR]

There is considerable uncertainty over whether any one dietary pattern broadly facilitates weight loss or maintenance of weight loss, and current dietary guidelines recommend a spectrum of dietary composition for the general population. However, emerging evidence suggests that specific dietary compositions may work better for identifiable groups of overweight/obese individuals based on their individual metabolic status. In particular, characteristics of insulin dynamics, such as insulin sensitivity or insulin secretion status, may interact with diets that vary in macronutrient composition to influence the weight loss achieved with a hypocaloric diet. [ABSTRACT FROM AUTHOR]

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, distribution, 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. [ABSTRACT FROM AUTHOR]

Background. Low body mass index (BMI) and micronutrient deficiencies are associated with increased morbidity and mortality rates in old age. Whether adverse patterns of dietary variety predict both low BMI and low micronutrient intakes in older adults was investigated. Methods. A cross-sectional analysis of national survey data was conducted in 1174 healthy adult men and women (ages 21 to 90 years) who provided physiologically plausible dietary data in the 1994-1996 Continuing Survey of Food Intakes by Individuals. Measurements included reported energy intake, protein intake (percentage meeting Recommended Dietary Allowance), micronutrient intakes (percentage meeting Estimated Average Requirements for 14 micronutrients), and BMI. Results. Adults who were 61 years or older consumed a greater total variety of foods, chose foods from a wider range of food groups, had a greater variety of micronutrient-dense foods and energy-weak foods, and had a lower variety of micronutrient-weak foods compared with adults ages 21 to 60 years (p < .05 to .001). However, older adults with low BMIs (<22 kg/m²) consumed a lower variety of energy-dense foods compared with older adults with higher BMIs (p < .05). The variety of energy-dense foods predicted both energy intake and BMI at all ages in multiple regression models controlling for confounding variables (R² = .124 for energy, R² = .574 for BMI, p < .001). A higher percentage of older persons had inadequate micronutrient intakes compared with younger persons (p < .05), especially vitamin E, calcium, and magnesium, but consumption of a particularly wide variety of micronutrient-rich foods helped counterbalance these trends (p < .05). Older adults who had a low BMI and consumed a low variety of micronutrient-dense foods were particularly at nutritional risk, with only 65.4% consuming the Recommended Dietary Allowance for protein and none meeting the Estimated Average Requirements for all 14 micronutrients. Conclusions. In contrast to previous suggestions that older persons consume a monotonous diet, this study showed that adults who were 61 years or older consumed a greater total food variety, and a greater variety of micronutrient-dense and energy-weak foods, compared with adults who were 60 years or younger. Although consumption of a low variety of energy-dense foods may contribute to reduced energy intake and body weight at any age, the variety of micronutrient-dense foods consumed needs to increase in old age to prevent micronutrient deficiencies. These findings suggest that all adults need advice on the changing needs for dietary variety with aging to maintain health, and that older persons with low BMI are particularly vulnerable to dietary shortfalls. [ABSTRACT FROM AUTHOR]

Background: Low body mass index (BMI) and micronutrient deficiencies are associated with increased morbidity and mortality rates in old age. Whether adverse patterns of dietary variety predict both low BMI and low micronutrient intakes in older adults was investigated.Methods: A cross-sectional analysis of national survey data was conducted in 1174 healthy adult men and women (ages 21 to 90 years) who provided physiologically plausible dietary data in the 1994-1996 Continuing Survey of Food Intakes by Individuals. Measurements included reported energy intake, protein intake (percentage meeting Recommended Dietary Allowance), micronutrient intakes (percentage meeting Estimated Average Requirements for 14 micronutrients), and BMI.Results: Adults who were 61 years or older consumed a greater total variety of foods, chose foods from a wider range of food groups, had a greater variety of micronutrient-dense foods and energy-weak foods, and had a lower variety of micronutrient-weak foods compared with adults ages 21 to 60 years (p < .05 to.001). However, older adults with low BMIs (< 22 kg/m2) consumed a lower variety of energy-dense foods compared with older adults with higher BMIs (p < .05). The variety of energy-dense foods predicted both energy intake and BMI at all ages in multiple regression models controlling for confounding variables (R2 = .124 for energy, R2 = .574 for BMI, p < .001). A higher percentage of older persons had inadequate micronutrient intakes compared with younger persons (p < .05), especially vitamin E, calcium, and magnesium, but consumption of a particularly wide variety of micronutrient-rich foods helped counterbalance these trends (p < .05). Older adults who had a low BMI and consumed a low variety of micronutrient-dense foods were particularly at nutritional risk, with only 65.4% consuming the Recommended Dietary Allowance for protein and none meeting the Estimated Average Requirements for all 14 micronutrients.Conclusions: In contrast to previous suggestions that older persons consume a monotonous diet, this study showed that adults who were 61 years or older consumed a greater total food variety, and a greater variety of micronutrient-dense and energy-weak foods, compared with adults who were 60 years or younger. Although consumption of a low variety of energy-dense foods may contribute to reduced energy intake and body weight at any age, the variety of micronutrient-dense foods consumed needs to increase in old age to prevent micronutrient deficiencies. These findings suggest that all adults need advice on the changing needs for dietary variety with aging to maintain health, and that older persons with low BMI are particularly vulnerable to dietary shortfalls. [ABSTRACT FROM AUTHOR]

Obesity, cardiovascular disease, and type 2 diabetes mellitus are now prevalent among adults living in developing countries; these chronic diseases affect socioeconomically disadvantaged adults living in impoverished families with undernourished children. This review summarizes data from Brazil -- a developing country undergoing the nutrition transition -- suggesting an association between childhood undernutrition and obesity and chronic degenerative disease. Potential mechanisms for the association include long-term effects of childhood undernutrition on energy expenditure, fat oxidation, regulation of food intake, susceptibility to the effects of high-fat diets, and altered insulin sensitivity. The combination of childhood undernutrition and adult chronic degenerative disease results in enormous social and economic burdens for developing countries. Further research is urgently needed to examine the effect of childhood undernutrition on risk of obesity and chronic degenerative diseases; one goal of such research would be to determine and provide low-cost methods for prevention and treatment. [ABSTRACT FROM AUTHOR]

Recommendations for increased consumption of protein are among the most common approaches of popular or fad diets. This review summarizes the effects of dietary protein on satiety, energy intake, thermogenesis, and weight loss, as well as its effect on a variety of health outcomes in adults. In short-term studies, dietary protein modulates energy intake via the sensation of satiety and increases total energy expenditure by increasing the thermic effect of feeding. Whereas these effects did not contribute to weight and fat loss in those studies in which energy intake was fixed, one ad libitum study does suggest that a high-protein diet results in a greater decrease in energy intake, and therefore greater weight and fat loss. In terms of safety, there is little long-term information on the health effects of high-protein diets. From the available data, however, it is evident that the consumption of protein greater than two to three times the U.S. Recommended Daily Allowance contributes to urinary calcium loss and may, in the long term, predispose to bone loss. Caution with these diets is recommended in those individuals who may be predisposed to nephrolithiasis or kidney disease, and particularly in those with diabetes mellitus. [ABSTRACT FROM AUTHOR]

Focuses on the extent to which eating behavior influences the long-term health of older women. Subject recruitment and data collection; Assessment of dietary restraint, disinhibition and hunger; Discussion on the relationships of eating behavior and morbidity in regression models.

Summarizes the effects of dietary energy density (ED) on energy regulation, in particular when ED is changed by manipulating different dietary constituents such as fat, fat plus fiber, water, or type of sweetener. Definition of dietary ED; Roles of ED in energy regulation; Historic and epidemiologic data on dietary ED; Effects of ED on hunger and satiety; Effects of ED on energy intake and body weight.

Examines the influence of dietary fiber intake on weight enhancement in the United States. Association of dietary fiber with hunger, satiety, energy intake and body composition; Evidence of energy suppression among obese individuals; Insufficiency of information comparing fiber types.

Background: Dietary restraint, a term used to describe the intentional control of food intake to prevent weight gain or promote weight loss, is commonly practiced by older adults, but little is known about its effects on physiology and metabolism.Methods: We therefore compared a wide range of parameters between groups of healthy non-obese postmenopausal women classified psychometrically as unrestrained eaters (body mass index [BMI] 23.8 +/- 0.6 [SEM] kg/m(2), n = 28) or restrained eaters (BMI 24.5 +/- 0.5, n = 39). Measurements were made of reported micronutrient intakes, cardiopulmonary function, hematology, body temperature, skin thickness, bone mass, and immune function; in addition, self-perceived health, mood, and some dimensions of eating behavior were assessed by questionnaire.Results: Macronutrient and micronutrient intakes were not significantly different between restrained and unrestrained eaters reporting energy intake to within 30% of predicted total energy expenditure. Restrained eaters had significantly lower hemoglobin (12.9 +/- 0.1 [SEM] vs 13.2 +/- 0.1 g/dl; p <.05), but values were within the normal range in both groups. In addition, restrained eaters scored significantly higher on the Eating Attitudes Test (p <.01) and drive-for-thinness (p <.001) and maturity fears (p <.05) subscores of the Eating Disorders Inventory, but values were again within the normal range. No other parameter differed significantly between groups.Conclusions: In this normal-weight population, restrained eating was not associated with detrimental effects in a wide range of physiological, metabolic, and health characteristics. Further work is needed to determine the relevance of these results to the general population. [ABSTRACT FROM AUTHOR]

Reports on the United States Centers for Disease Control and Prevention's publication of the new childhood growth percentiles, designed to replace the 1977 National Center for Health Statistics percentiles. Uses of the percentile charts; International definitions for overweight and obesity in childhood.

Caloric restriction (CR) reduces the rate of aging and increases life span in all small animal species studied to date, but the effects of CR in humans remain uncertain. This review summarizes current knowledge of the effects of CR in nonhuman primates and humans. The results suggest that CR has a range of beneficial effects in nonhuman primates studied under laboratory conditions, and short-term markers of CR seen in animal models appear to occur in humans subject to CR also. However, the overall benefit of CR in human populations remains to be established, and studies in human populations are needed. [ABSTRACT FROM AUTHOR]

Recent studies have suggested a short-term impairment in the regulation of food intake in older adults, but further studies are needed to determine if a longer-term impairment exists and to identify underlying causes. Changes in body weight and composition were measured over a 6-week underfeeding study and a 6-month follow-up period in healthy young (n = 23) and older (OLD, n = 18) men and women. The young adults were either normal weight (YNW, n = 12) or overweight (YOW, n = 11). Energy intakes during underfeeding were 896 +/- 18 (SEM) kcal less than weight-maintenance energy requirements determined prior to underfeeding. In addition, changes in perceived hunger during underfeeding were monitored in a subgroup (n = 19). OLD and YOW subjects lost significantly more weight during underfeeding than did YNW subjects (p = .025 and .000, respectively), and they did not gain back significant weight in the 6-month follow-up. In addition, OLD subjects reported a significantly lower frequency of hunger during underfeeding (p = .05). There was no significant difference among groups in the relationship between weight lost and fat-free mass lost. Healthy OLD adults have an impaired ability to regulate food intake over at least 6 months following underfeeding compared with YNW adults, and a reduction in their perceived frequency of hunger may be a contributing factor. [ABSTRACT FROM AUTHOR]

Examines whether consumption of high-glycemic index (GI) carbohydrates may be a contributing factor to obesity. Definition of GI; High-GI carbohydrates' effect of increasing hunger; Individual susceptibility; Theories of energy regulation; Diet to prevent overeating.

Emphasizes the need for regular monitoring of body weight to detect unintentional weight loss in older individuals. Testable ways to minimize the impact of the anorexia of aging on body weight through improved dietary management; Impaired regulation of food intake in old age.

Evaluates the effects of dietary fat and fat substitutes on obesity and energy regulation in the United States, referencing data from studies conducted on the issue. Relationship between dietary fat and obesity; Concept associated with dietary fat and energy regulations; Comparison between dietary fat and energy density.

Individual susceptibility to obesity is recognized to be influenced significantly by genetic inheritance. Recently, candidate obesity genes have been identified that may contribute to the inheritance of body fat mass and the partitioning of fat between central and peripheral fat depots. In studies of animal models of obesity, the genetic basis for obesity in the obese (Ob/Ob) mouse, the Fat mouse, and the Yellow (Vvy) mouse has been identified. Further research is needed to determine whether abnormalities in these genes contribute to human obesity as well. In studies of humans, sequence variation in at least six genes has been linked to increased body fatness and/ or susceptibility to obesity. In addition, five other encoding genes have been linked to a disproportionate storage of fat in the abdominal region. These genes identified in studies of humans are currently thought to be modifying or background genes, each separately conferring a modest increase in susceptibility to fatness. Further research is needed to identify additional candidate genes that confer susceptibility to obesity and to determine the relative importance of each one in a range of human populations with distinct environments. [ABSTRACT FROM AUTHOR]

Reviews the function of energy expenditure in energy regulation. Description of the same.

Focuses on a study that involves underfeeding on changes in energy expenditure, substrate oxidation and energy deposition between young and older men. Methods used; Results; Discussion.

Focuses on several studies on the possible causes of negative energy balance in older individuals. Study methodologies; Results of these studies; Findings that the combination of unexpected high energy needs, and an inability to accurately control energy intake, increases the risk for negative energy balance and associated body fat and protein losses in older individuals; What was concluded.

Age-related changes in serum levels of somatomedin-like growth factors were measured using a bioassay based on myoblast proliferation in culture. The correspondence of this assay to thymidine incorporation and sulfation factor assays for somatomedins was demonstrated. Comparisons involved individual serum samples from a total of 28 rats at each of three age ranges (young = 2 to 6 month, middle-aged = 12 to 16 month, and old = 24 to 28 month) in five separate experiments. A small (10%) decrease in levels of somatomedin-like activity was observed between young and middle-aged animals, with a greater (20 to 40%) subsequent decrease in old rats. Assays of mixed samples indicated that the age-related decreases in somatomedin-like activity could not be attributed to increases in circulating levels of a dissociable inhibitor of this activity. Paired comparisons of amino acid uptake by isolated omohyoideus muscles from rats of the specified ages suggested that there were no significant age-related changes in response of these muscles to a somatomedin analog. [ABSTRACT FROM PUBLISHER]

Supports routine recommendation of multivitamin/mineral supplements for young children as a way to prevent the adverse effects of early-life nutrition deficiencies suggested in multiple studies. Documentation of low micronutrient intakes by young children through multiple dietary surveys; Consequences of low calcium intakes.

Examines the magnitude of weight gain during the holiday season among adults in the United States. Contribution of holiday weight gain to annual obesity statistics; Implication of the holiday season for the eating habits of individuals; Public belief on weight gain during the holidays compared to other seasons of the year.

Introduction: Effective, standardized, and easily accessible weight management programs are urgently needed for military beneficiaries. Videoconference interventions have the potential for widespread scaling, and can provide both real time interaction and flexibility in delivery times regardless of location, but there is little information on their effectiveness and acceptability.Materials and Methods: This study as part of a larger weight loss trial describes the videoconference adaption of Group Lifestyle Balance (GLB) program, a community group-based Diabetes Prevention Program intervention, and provides a comparison of weight loss and meeting attendance between in-person and videoconference delivery modes over 12 weeks in adult family members of military service members. Forty-three participants were enrolled from two military installations and received either the videoconference-adapted or an in-person GLB program in a non-randomized trial design. Differences in program attendance and percent weight lost at 12 weeks were compared by independent samples t-tests and nonparametric methods. Group differences in the percentage of weight lost over the 12-week period were analyzed using a linear mixed model.Results: All GLB intervention components were successfully delivered by videoconference with minor adaptations for the different delivery mechanism. Participant retention was 70% and 96% in the in-person and videoconference groups, respectively (p = 0.04). Completing participants in both groups lost a significant percent body weight over the 12 week intervention (p < 0.001) and there was no difference in percent body weight after 12 weeks of intervention (6.2 ± 3.2% and 5.3 ± 3.4% for in-person and videoconference at 12 weeks, respectively; p = 0.60).Conclusion: This study describes the first videoconference adaption of the GLB program for use in military families. Attrition was lower in the videoconference group, and there were a similar levels of weight loss in both groups regardless of delivery modality. Videoconference weight loss interventions are effective and feasible for scaling to support healthy weight management in military as well as civilian populations. [ABSTRACT FROM AUTHOR]