Physical activity and subsistence pattern of the Huli, a Papua New Guinea Highland population

Several studies on human energetics have been conducted in developed and developing countries, but very few simultaneously measured time use and energy expenditure. Only a few quantitatively compared subsistence patterns between rural and urban dwellers of an identical population. Here we present the daily physical activity level (PAL), physical exertion, time, and energy expenditure in contrasting subsistence/occupational activities of Papua New Guinea Highlanders, comparing 27 rural villagers (15 men, 12 women) who maintained traditional subsistence agriculture, with 29 urban migrants (14 men, 15 women) who engaged in cash-earning work. A large sex inequality in the division of labor was noted between rural males and females, but not among urban dwellers. Rural-urban comparison indicated sex differences in urbanization. For urban men, the reduction of physical exertion level during work, from energy-consuming agricultural work to sedentary cash-earning work, together with significantly extended work time (by 261 min/day, P < 0.001), led to an increase in work energy expenditure (15-29% of PAL). In contrast, urban women who spent almost equal time at work relative to rural women showed a lower energy expenditure (18% compared to 26% of PAL). The associations with urbanization included a gain in body weight (by 6.4 kg for either sex) and reduced PAL (by 7%, not significant in men; 13%, P < 0.01 in women). Further research is needed to elucidate the effects of urbanization on time use, energy expenditure, and PAL, by comparing rural residents with urban migrants in the same population.     

Obesity and labor market outcomes among legal immigrants to the United States from developing countries

This paper studies the association between weight and labor market outcomes among legal immigrants to the United States from developing countries using the first nationally representative survey of such individuals. We find that being overweight or obese is associated with a lower probability of employment among women who have been in the U.S. less than five years, but we find no such correlation among men who have been in the U.S. less than five years, or among women or men who have been in the U.S. longer than five years. We generally find no significant association between weight and either wages, sector of employment, or work limitations for either women or men. Possible explanations for these findings are discussed.     

Obesity and the labor market: A fresh look at the weight penalty

This paper applies semiparametric regression models to shed light on the relationship between body weight and labor market outcomes in Germany. We find conclusive evidence that these relationships are poorly described by linear or quadratic OLS specifications. Women's wages and employment probabilities do not follow a linear relationship and are highest at a body weight far below the clinical threshold of obesity. This indicates that looks, rather than health, is the driving force behind the adverse labor market outcomes to which overweight women are subject. Further support is lent to this notion by the fact that wage penalties for overweight and obese women are only observable in white-collar occupations. On the other hand, bigger appears to be better in the case of men, for whom employment prospects increase with weight, albeit with diminishing returns. However, underweight men in blue-collar jobs earn lower wages because they lack the muscular strength required in such occupations.     

Impact of body mass on job quality

The current study explores the association between body mass and job quality, a composite measurement of job characteristics, for adults. We use nationally representative data from the Korean Labor and Income Panel Study for the years 2005, 2007, and 2008 with 7282 person-year observations for men and 4611 for women. A Quality of Work Index (QWI) is calculated based on work content, job security, the possibilities for improvement, compensation, work conditions, and interpersonal relationships at work. The key independent variable is the body mass index (kg/m²) splined at 18.5, 25, and 30. For men, BMI is positively associated with the QWI only in the normal weight segment (+0.19 percentage points at the 10th, +0.28 at the 50th, +0.32 at the 75th, +0.34 at the 90th, and +0.48 at the 95th quantiles). A unit increase in the BMI for women is associated with a lower QWI at the lower quantiles in the normal weight segment (−0.28 at the 5th, −0.19 at the 10th, and −0.25 percentage points at the 25th quantiles) and at the upper quantiles in the overweight segment (−1.15 at the 90th and −1.66 percentage points at the 95th quantiles). The results imply a spill-over cost of overweight or obesity beyond its impact on health in terms of success in the labor market.     

Physical Activity in Confined Conditions as an Indicator of Free‐Living Physical Activity

Objective: The main determinants of daily energy expenditure are body size and physical activity. Activity energy expenditure is the most variable component of total energy expenditure. It was assessed whether the physical activity level in confined conditions is an indicator of free‐living physical activity. Research Methods and Procedures: Activity energy expenditure was measured over 1 day in a confined environment of a respiration chamber (floor space, 7.0 m²), where activities were restricted to low‐intensity activities of daily living, and over 2 weeks in a free‐living environment using doubly labeled water. Subjects were 16 women and 29 men (age, 31 ± 10 years; BMI, 24.2 ± 2.7 kg/m²). Results: The free‐living activity level of the subjects, as a multiple of resting energy expenditure, was 1.76 ± 0.13. Activity energy expenditure in the chamber was 47 ± 13% of the value in daily life, and the two values were correlated (r = 0.50, p < 0.001; partial correlation corrected for age, gender, and BMI: 0.40, p < 0.01). The chamber value explained 25% of the total variance in free‐living activity energy expenditure. Discussion: The activity level of a subject under sedentary conditions is an indicator of activity energy expenditure in daily life, showing the importance of nonexercise activity for daily energy expenditure.     

Hypertension and Obesity in Adults Living in a High HIV Prevalence Rural Area in South Africa

Hypertension and excess body weight are major risk factors of cardiovascular morbidity and mortality in developing countries. In countries with a high HIV prevalence, it is unknown how increased antiretroviral treatment and care (ART) coverage has affected the prevalence of overweight, obesity, and hypertension. We conducted a health survey in 2010 based on the WHO STEPwise approach in 14,198 adult resident participants of a demographic surveillance area in rural South Africa to investigate factors associated with hypertension and excess weight including HIV infection and ART status. Women had a significantly higher median body mass index (BMI) than men (26.4 vs. 21.2 kg/m², p<0.001). The prevalence of obesity (BMI≥30 kg/m²) in women (31.3%, 95% confidence interval (CI) 30.2–32.4) was 6.5 times higher than in men (4.9%, 95% CI 4.1–5.7), whereas prevalence of hypertension (systolic or diastolic blood pressure≥140 or 90 mm Hg, respectively) was 1.4 times higher in women than in men (28.5% vs 20.8%, p<0.001). In multivariable regression analysis, both hypertension and obesity were significantly associated with sex, age, HIV and ART status. The BMI of women and men on ART was on average 3.8 (95% CI 3.2–3.8) and 1.7 (95% CI 0.9–2.5) kg/m² lower than of HIV-negative women and men, respectively. The BMI of HIV-infected women and men not on ART was on average 1.2 (95% CI 0.8–1.6) and 0.4 (95% CI -0.1–0.9) kg/m² lower than of HIV-negative women and men, respectively. Obesity was a bigger risk factor for hypertension in men (adjusted odds ratio (aOR) 2.99, 95% CI 2.00–4.48) than in women (aOR 1.64, 95% CI 1.39–1.92) and overweight (25≤BMI<30) was a significant risk factor for men only (aOR 1.53 95% CI 1.14–2.06). Our study suggests that, cardiovascular risk factors of hypertension and obesity differ substantially between women and men in rural South Africa.     

Varying patterns of BMI increase in sex and birth cohorts of Korean adults

Objective: The Korean population has recently experienced a rapid increase in obesity associated with lifestyle changes arising from economic growth. We examined trends in BMI by analyzing sex‐specific birth cohorts using 3,400,727 measurements from 1,662,477 Korean adults. Research Methods and Procedures: Birth cohort data were collected from the employees of government organizations and schools and their dependents, 20 to 65 years of age, who participated in health examinations provided by the Korean National Health Insurance Corporation in 1992, 1996, and 2000. Results: The prevalence of obesity (BMI ≥ 30 kg/m²) was 0.8% among men and 0.3% among women in 1992, but by 2000, it had increased 2.5‐fold to 2.0% in men and 2.3‐fold to 0.7% in women. Over the 8‐year period, the mean BMI increased 0.8 kg/m² in men and 0.3 kg/m² in women. The rate of BMI increase over the 8 years varied markedly among the sex‐specific birth cohorts, with the steepest slopes representing the youngest men (0.2 kg/m² per year). Discussion: National health promotion activities should target younger men to prevent an increase in obesity‐related morbidity and mortality.     

Entry Body Mass and Earnings: Once Penalized,Ever Penalized?

It has previously been reported that an individual’s body mass index (BMI) contemporaneously penalizes wages for women, but has no effect and sometimes rewards wages for men. In young adults, we estimate the association of BMI status with initial wages to assess whether initial BMI at the beginning of an individual’s career affects initial and later earnings. We pooled data from 388 men and 305 women, aged 20–40 years, with BMI information for the first year of employment, using the Korean Labor and Income Panel Study. A labor market penalty for a higher BMI among women was found only for overweight or obese segments, particularly those with relatively higher monthly wages. Meanwhile, a higher BMI in underweight or normal weight segments could reward employment probability for women and monthly wages for men. Such rewards of relatively higher monthly wages were also estimated for men in the overweight segment. Our findings suggest discrimination as one factor penalizing higher BMI in the labor market.     

Income and body mass index in Europe

The problem of obesity is alarming public health authorities around the world. Therefore, it is important to study its determinants. In this paper, we explore the empirical relationship between household income and body mass index (BMI) in nine European Union countries. Our findings suggest that, in general, the association is negative for women and nonexistent for men. Moreover, once we decompose household income into “own labor earnings” and “other household income”, we find that the different relationship for men and women appears to be driven by the negative relationship between BMI and “own labor earnings” for women.     

Changes in body mass index and smoking habits have a different impact on hemoglobin concentration in men and women: A longitudinal follow-up of the tromsø study, 1994–2002

Background: Body mass index (BMI) and smoking have been positively associated with hemoglobin concentration, and both are risk factors for cardiovascular disease.Objective: The aim of this study was to assess whether there were sex differences in how changes in BMI and smoking habits influenced hemoglobin concentration.Methods: In 1994–95 and 2001–02, a longitudinal, population-based study was conducted in the municipality of Tromsø, in northern Norway. Inhabitants aged ≥25 years were invited to participate. Participants replied to a questionnaire regarding health, physical activity, coffee and alcohol consumption, and smoking habits. Blood samples were drawn to analyze hemoglobin concentration.All analyses were performed separately for each sex. Differences between 1994–95 and 2001–02 were examined with t or χ² (McNemar) tests for paired data. Cross-sectional comparisons were made using 2-sample t tests. Different models of univariate and multiple linear regression analyses were used to investigate the impact of the various variables on hemoglobin change.Results: Data from a total of 2105 men and 2945 women were examined. At baseline, mean age was 58.9 years for men (range, 25–78 years) and 57.8 years for women (range, 25–82 years); mean BMI was 26.1 kg/m² for men and 25.8 kg/m² for women. In men, hemoglobin decreased with age, on average from 147.5 to 145.1 g/L. In women, hemoglobin decreased from 135.6 to 134.7 g/L, but increased with increasing age up to 54 years, and thereafter decreased gradually. Mean BMI increased 0.8 kg/m² in men and 1.2 kg/m² in women. In total, 394 of 2057 men (19%) and 499 of 2889 women (17%) stopped smoking or smoked fewer cigarettes per day. In a univariate regression model, an increase of 1 kg/m² in BMI was associated with an increase in hemoglobin of 1.1 g/L (95% CI, 0.84 to 1.27) in men and 0.4 g/L (95% CI, 0.30 to 0.56) in women. In another univariate model, smoking cessation was associated with a decrease in hemoglobin of 1.9 g/L (95% CI, ?3.32 to ?0.56) in men and 1.7 g/L (95% CI, ?2.93 to ?0.56) in women. In men who smoked less and had a BMI increase of >2.5 kg/m², hemoglobin decreased 0.3 g/L. In contrast, hemoglobin decreased 3.4 g/L in men who smoked less and lost weight (P for trend, < 0.001 by changing BMI). Women who smoked less had a decrease in hemoglobin independent of BMI changes.Conclusions: The positive association between an increase in BMI and hemoglobin was stronger in men than in women. The effect of smoking reduction on hemoglobin was attenuated with increasing BMI in men, but not in women.     

Associations of Aging and Birth Cohort with Body Mass Index in a Biethnic Cohort

Objective: To examine associations of aging and birth cohort with body mass index (BMI) in a biethnic cohort. Research Methods and Procedures: This was a longitudinal closed cohort study of 14, 500 white and African‐American men and women, 45 to 64 years of age, followed for 9 years. Aging was defined as the length of the interval in years between baseline and following visits. Birth cohort was defined by the year in which participants were born. Mixed model analyses were used to examine associations of aging, birth cohort, and BMI in four ethnicity‐gender groups. Results: We found that aging was associated with an increase in BMI in white and African‐American men and women. The associations between aging and BMI were stronger in the younger birth cohorts. Except for white women, younger birth cohort was associated with a higher BMI. After adjusting for aging, birth cohort was associated with an increase in BMI of 0.1 kg/m² [95% confidence interval (95% CI): ?0.1, 0.3] among white women. The corresponding values for African‐American women, white men, and African‐American men are 0.5 kg/m² (95% CI: 0.1, 0.9), 0.6 kg/m² (95% CI: 0.4, 0.8), and 0.6 kg/m² (95% CI: 0.2, 1.0), respectively. Discussion: Our analyses show that, in all except white women, people in this age range who were born later have a higher BMI at the same attained age. In all groups, people who are born later gained more weight as they aged. In general, subjects ages 45 to 64 years gained weight as they aged 9 years.     

Relationships Between the Body Mass Index and Body Composition

The aims of this study were to evaluate the Body Mass Index (BMI) (weight/stature²) as a proxy for percent body fat (%BF) and to determine its association with fat-free mass (FFM). Multivariate analysis of variance and partial correlations were used to examine relationships between BMI and %BF and FFM from densitometry for 504 men and 511 women, aged 20 to 45 years. Sensitivity/specificity analyses used cut offs of 28 kg/m² in men and 26 kg/m² in women for BMI, and 25% in men and 33% in women for %BF. Significantly higher associations existed in each gender between BMI and %BF in the upper BMI tertile than in the lower BMI tertiles. In the lower BMI tertiles, correlations between BMI and FFM were approximately twice as large as those between BMI and %BF. The BMI correctly identified about 44% of obese men, and 52% of obese women when obesity was determined from %BF. BMI is an uncertain diagnostic index of obesity. Results of Receiver Operator Characteristic (ROC) analyses using %BF and total body fat, both provided a BMI of 25 kg/m² in men and 23 kg/m² in women as diagnostic screening cut offs for obesity.     

Gender Differences in the Relationship between Personality Dimensions and Relative Body Weight

Objective: The relationship between body mass index (BMI: kg/m²) and personality seems to differ for men and women, although these effects may be driven by the extremes of the BMI distribution. It is unclear whether these associations exist for most individuals in the relatively normal range of BMI scores, excluding the thinnest and heaviest extremes in the population. We tested the association of BMI with neuroticism, extraversion, and psychoticism with a trimmed BMI sample. Research Methods and Procedures: Using a cross‐sectional design, we tested the association of BMI with the aforementioned psychological variables in a British population‐based sample. Participants were 7889 adult men and women (30 to 50 years old) selectively sampled from four counties in west England. Participants reported their height and weight and completed the Eysenck Personality Inventory (EPQ). We tested the association of BMI with the EPQ subscales among individuals with BMI ≥19.16 kg/m² and ≤37.78 kg/m², i.e., the approximate 5th and 95th percentiles. Results: Despite elimination of extreme BMIs, different associations between BMI and EPQ subscales emerged for men and women. Among women, increasing BMI was significantly associated with increased neuroticism and reduced extraversion. Among men, increasing BMI was associated with increased extraversion and psychoticism. In all cases, the magnitude of the association was very small. Discussion: Increasing BMI was associated with potentially poorer adjustment among women but better adjustment among men. These findings are consistent with recent reports and, taken together, suggest that these patterns are not accounted for solely by the extremes of the BMI distribution.     

Evolution of obesity by social status in France, 1981-2003

Although France is less affected by the rise in obesity than neighboring countries, the prevalence of obesity has increased, changing the distribution of this pathology in the population. We analyze this evolution by social status, education, income and gender, region of residence, using the three French national Health Surveys conducted in 1981, 1992 and 2003. The average body weight of both women and men has increased in France since 1981 and accelerated since the 1990s. This trend is obtained among all age groups. Nevertheless, this process did not affect all socioeconomic groups similarly. Geographical differences increased between north-east, where the prevalence of obesity is higher, and the Mediterranean region, where it is lower. Likewise, the gap between social and occupational categories has greatly widened: obesity has increased much faster among farmers and blue-collar workers than among managers and professionals. In contrast to women, poorer men are not more likely to be more obese than others. Our findings suggest that differences in BMI values increased substantially among social groups in France, in particular among women.     

Modeling the Impact of Adjustable Gastric Banding on Survival in Patients with Morbid Obesity

Objective: Morbid obesity is associated with premature death. Adjustable gastric banding may lead to substantial weight loss in patients with morbid obesity. Little is known about the impact of weight loss on survival after adjustable gastric banding. We therefore developed a mathematical model to estimate life expectancy in patients with a body mass index (BMI) ≥40 kg/m² undergoing bariatric surgery. Research Methods and Procedures: We developed a nonhomogeneous Markov chain consisting of five states: the absorbing state (“dead”) and the four recurrent states BMI ≥40 kg/m², BMI 36 to 39 kg/m², BMI 32 to 35 kg/m², and BMI 25 to 31 kg/m². Scenarios of weight loss and age‐ and sex‐dependent risk of death, as well as BMI‐dependent excess mortality were extracted from life tables and published literature. All patients entered the model through the state of BMI ≥40 kg/m². Results: In men aged either 18 or 65 years at the time of surgery, who moved from the state BMI ≥40 kg/m² to the next lower state of BMI 36 to 39 kg/m², life expectancy increased by 3 and 0.7 years, respectively. In women aged either 18 or 65 years at the time of surgery, who moved from the state BMI ≥40 kg/m² to the next lower state BMI 36 to 39 kg/m², life expectancy increased by 4.5 and 2.6 years, respectively. Weight loss to lower BMI strata resulted in further gains of life expectancy in both men and women. Discussion: Within the limitations of the modeling study, adjustable gastric banding in patients with morbid obesity may substantially increase life expectancy.     

Work‐Related Physical Activity Is Not Associated with Body Mass Index and Obesity

Objective: To analyze the association of work‐related physical activity (WRPA) and leisure‐time physical activity (LTPA) with body mass index (BMI) and obesity in the Spanish adult population aged 20 to 60 years. Research Methods and Procedures: The data were taken from the 1993 Spanish National Health Survey. We analyzed a sample of 12,044 men and women representative of the Spanish population aged 20 to 60 years. BMI and frequency of obesity (BMI ≥ 30 kg/m²) were obtained from self‐reported weight and height. Multiple linear regression and logistic regression models were constructed, adjusting for the main confounding factors. WRPA and LTPA were measured by two questions to classify subjects into four categories of physical activity. Results: Neither mean BMI nor percentage of obesity varied significantly (p > 0.05) by WRPA. Mean BMI was significantly higher (p < 0.01) in those who were inactive in their leisure time (25.90 kg/m² in men and 24.43 kg/m² in women) than in those who reported vigorous activity (24.42 kg/m² and 22.97 kg/m² in men and women, respectively). The odds ration (OR) for obesity decreased with increasing level of LTPA in both men (OR of 0.64 for vigorous activity) and women (OR = 0.68), showing a statistically significant dose‐response relation in both men (for linear trend, p = 0.0021) and women (p = 0.0245). Discussion: These results raise questions about the association between WRPA and obesity and suggest the need to reexamine models of the obesity epidemic that point to automation of the workplace as one of the major explanatory factors.     

Prevalence of Overweight and Obesity in Elderly People in Spain

Objective: To estimate the prevalence of obesity and overweight in the older adult population in Spain by sex, age, and educational level. Research Methods and Procedures: A cross‐sectional study was carried out in 2001 in a sample of 4009 persons representative of the noninstitutionalized population ≥60 years of age. Anthropometric measurements (BMI and waist circumference) were obtained using standardized techniques and equipment. Overweight was considered at a BMI of 25 to 29.9 kg/m² and obesity at a BMI of ≥30 kg/m². Central obesity was considered at a waist circumference of >102 cm in men and >88 cm in women. Results: The mean BMI was 28.2 kg/m² in men and 29.3 kg/m² in women. The prevalence of overweight and obesity in men was 49% and 31.5%, respectively. The corresponding percentages in women were 39.8% and 40.8%. The prevalence of obesity was higher in persons with no education than in those with third level education (i.e., university studies), especially among women (41.8% vs. 17.5%). The prevalence of central obesity was 48.4% in men and 78.4% in women. Differences by educational level were seen in only women, in whom the prevalence of central obesity was 80.9% in those with no education and 59% in those with third‐level education. Discussion: The prevalence of overweight and obesity in the Spanish adult elderly population is very high. Some other populations show similar prevalences, especially in Mediterranean countries. Socioeconomic conditions in Spain during the years these cohorts were born may partly explain the high‐frequency of obesity.     

Weight Loss and Gender: An Examination of Physician Attitudes

Objective: The purpose of this study was to investigate physician attitudes toward the treatment of overweight and obese individuals and to evaluate potential gender differences in treatment recommendations. Research Methods and Procedures: A survey describing several hypothetical patients was sent to 700 randomly selected physicians; 209 (29.9%) returned the survey. Two versions of the questionnaire (one for men and one for women) described three hypothetical patients at three levels of body mass index (BMI) (32, 28, and 25 kg/m²). One‐half of the physicians received a version of the questionnaire describing the patients as women, and one‐half received a version describing the patients as men. Respondents answered questions about attitudes toward treatment and specific interventions and referrals they would view as appropriate. Results: Physicians were more likely to encourage women with a BMI of 25 kg/m² to lose weight than men with the same BMI, and indicated that they would suggest more treatment referrals for women than men. Men with a BMI of 32 kg/m² were more likely to be encouraged to lose weight than women with the identical BMI. Physicians were more likely to encourage weight loss and see treatment referrals as appropriate for patients with higher BMIs. Discussion: This study indicates that physicians treat male and female patients differently, with physicians more likely to encourage weight loss and provide referrals for women with a BMI of 25 kg/m² than for men with an identical BMI and less likely to encourage weight loss for women than men with a BMI of 32 kg/m².     

The reciprocal relationship between depressive symptoms and employment status

This paper analyzes the reciprocal lagged relationship between depressive symptoms and employment status. We find that severe depressive symptoms contribute to a 25.6% increase in subsequent non-employment rates, a 20.7% increase in non-participation rates and 34.2% increase in unemployment rates, for men. Similar, although weaker, marginal effects are found for women. However, we find no evidence for men and only limited evidence for women that unemployment, non-employment, or non-participation raises the risks of severe depressive symptoms. We observe an impact of labor market status on depressive symptoms only when using point-in-time measures.