Big Issue
Timothy Church et al.
PLoS ONE, May 2011, e19657
Background: The true causes of the obesity epidemic are not well understood and there are few longitudinal population-based data published examining this issue. The objective of this analysis was to examine trends in occupational physical activity during the past 5 decades and explore how these trends relate to concurrent changes in body weight in the U.S.
Methodology/Principal Findings: Analysis of energy expenditure for occupations in U.S. private industry since 1960 using data from the U.S. Bureau of Labor Statistics. Mean body weight was derived from the U.S. National Health and Nutrition Examination Surveys (NHANES). In the early 1960's almost half the jobs in private industry in the U.S. required at least moderate intensity physical activity whereas now less than 20% demand this level of energy expenditure. Since 1960 the estimated mean daily energy expenditure due to work related physical activity has dropped by more than 100 calories in both women and men. Energy balance model predicted weights based on change in occupation-related daily energy expenditure since 1960 for each NHANES examination period closely matched the actual change in weight for 40-50 year old men and women. For example from 1960-62 to 2003-06 we estimated that the occupation-related daily energy expenditure decreased by 142 calories in men. Given a baseline weight of 76.9 kg in 1960-02, we estimated that a 142 calories reduction would result in an increase in mean weight to 89.7 kg, which closely matched the mean NHANES weight of 91.8 kg in 2003-06. The results were similar for women.
Conclusion: Over the last 50 years in the U.S. we estimate that daily occupation-related energy expenditure has decreased by more than 100 calories, and this reduction in energy expenditure accounts for a significant portion of the increase in mean U.S. body weights for women and men.
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Focusing on food during lunch enhances lunch memory and decreases later snack intake
Suzanne Higgs & Jessica Donohoe
Appetite, forthcoming
Abstract:
We investigated whether eating lunch mindfully, in contrast to eating with distractions or no particular focus, reduces later snack intake and if this is related to a measure of meal memory. The design was between-subjects with three conditions. Twenty-nine female undergraduate students either ate a fixed lunch while 1) focusing on the sensory characteristics of the food as they ate (food focus group), 2) reading a newspaper article about food (food thoughts control group) or 3) in the absence of any secondary task (neutral control group). Cookie intake later that afternoon was measured as well as rated vividness of memory of the lunch. Participants ate significantly fewer cookies in the food focus group than in both the food thoughts control group or the neutral control group. Rated appetite before the snack session was lower in the food focus group than in the other two groups and rated vividness of lunch memory was higher. Rated vividness of lunch memory was negatively correlated with snack intake. These results suggest that enhancing meal memory by paying attention to food while eating can reduce later intake and are consistent with the suggestion that memory plays an important role in appetite control.
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Mind over milkshakes: Mindsets, not just nutrients, determine ghrelin response
Alia Crum et al.
Health Psychology, forthcoming
Objective: To test whether physiological satiation as measured by the gut peptide ghrelin may vary depending on the mindset in which one approaches consumption of food.
Methods: On 2 separate occasions, participants (n = 46) consumed a 380-calorie milkshake under the pretense that it was either a 620-calorie "indulgent" shake or a 140-calorie "sensible" shake. Ghrelin was measured via intravenous blood samples at 3 time points: baseline (20 min), anticipatory (60 min), and postconsumption (90 min). During the first interval (between 20 and 60 min) participants were asked to view and rate the (misleading) label of the shake. During the second interval (between 60 and 90 min) participants were asked to drink and rate the milkshake.
Results: The mindset of indulgence produced a dramatically steeper decline in ghrelin after consuming the shake, whereas the mindset of sensibility produced a relatively flat ghrelin response. Participants' satiety was consistent with what they believed they were consuming rather than the actual nutritional value of what they consumed.
Conclusions: The effect of food consumption on ghrelin may be psychologically mediated, and mindset meaningfully affects physiological responses to food.
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Tené Lewis et al.
American Journal of Epidemiology, 1 June 2011, Pages 1223-1231
Abstract:
The authors examined the association between self-reported experiences of discrimination and subtypes of abdominal fat (visceral, subcutaneous) in a population-based cohort of African-American and Caucasian women. Prior studies examining associations between discrimination and abdominal fat have yielded mixed results. A major limitation of this research has been the reliance on waist circumference, which may be a poor marker of visceral fat, particularly for African-American women. Participants were 402 (45% African-American, 55% Caucasian) middle-aged women from the Chicago, Illinois, site of the Study of Women's Health Across the Nation. Visceral and subcutaneous fat were assessed via computed tomography scans between 2002 and 2005. Linear regression models were conducted to test associations among discrimination and visceral and subcutaneous fat. After adjustment for age and race, every one-point increase on the discrimination scale was associated with a 13.03-cm2 higher amount of visceral fat (P = 0.04). This association remained significant after further adjustments for total body fat and relevant risk factors, including depressive symptoms. Discrimination was not associated with subcutaneous fat in minimally (P = 0.95) or fully adjusted models. Associations did not differ by race. Findings suggest that visceral fat may be one potential pathway through which experiences of discrimination increase cardiovascular risk.
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"A Thing of Beauty is a Joy Forever"?: Returns to Physical Attractiveness over the Life Course
Mads Meier Jæger
Social Forces, March 2011, Pages 983-1003
Abstract:
This article analyzes the effect of three aspects of physical attractiveness (facial attractiveness, Body Mass Index and height) on socio-economic and marital success over the life course. In a sample of high school graduates from Wisconsin followed from their late teens and until their mid-60s, I find that (1. taller men have higher earnings than shorter men throughout their careers, (2. women with more attractive faces and women with lower Body Mass Index have higher socio-economic status late in their careers, (3. men and women with more attractive faces are more likely to be married in youth, and (4. men and women's physical attractiveness is unrelated to the income and socio-economic status of their spouses. These results suggest that, first, physical attractiveness matters throughout the life course, second, attractiveness does not have a large quantitative effect on socio-economic and marital outcomes and third, different aspects of physical attractiveness matter differently for men and women.
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John Pucher et al.
American Journal of Public Health, forthcoming
Objectives: To assess changes in walking and cycling in the United States between 2001 and 2009.
Methods: The 2001 and 2009 National Household Travel Surveys were used to compute the frequency, duration, and distance of walking and cycling per capita. The population-weighted person and trip files were merged to calculate the prevalence of any walking and cycling and of walking and cycling at least 30 minutes per day.
Results: The average American made 17 more walk trips in 2009 than in 2001, covering 9 more miles per year, compared with only 2 more bike trips, and 5 more miles cycling. At the population level, the prevalence of "any walking" remained unchanged (about 18%), whereas walking at least 30 minutes per day increased from 7.2% to 8.0%. The prevalence of "any cycling" and cycling 30 minutes per day remained unchanged (1.7% and 0.9%, respectively). Active travel declined for women, children, and seniors, but increased among men, the middle aged, employed, well-educated, and persons without a car.
Conclusions: Walking increased slightly, whereas cycling levels stagnated, and the overall prevalence of active travel remained low. Improved infrastructure for walking and cycling must be combined with programs to encourage active travel among more groups, especially children, seniors, and women.
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Isolating the Effect of Major Depression on Obesity: Role of Selection Bias
Dhaval Dave, Jennifer Tennant & Gregory Colman
NBER Working Paper, May 2011
Abstract:
There is suggestive evidence that rates of major depression have risen markedly in the U.S. concurrent with the rise in obesity. The economic burden of depression, about $100 billion annually, is under-estimated if depression has a positive causal impact on obesity. If depression plays a causal role in increasing the prevalence of obesity, then policy interventions aimed at promoting mental health may also have the indirect benefits of promoting a healthy bodyweight. However, virtually the entire existing literature on the connection between the two conditions has examined merely whether they are significantly correlated, sometimes holding constant a limited set of demographic factors. This study utilizes multiple large-scale nationally-representative datasets to assess whether, and the extent to which, the positive association reflects a causal link from major depression to higher BMI and obesity. While contemporaneous effects are considered, the study primarily focuses on the effects of past and lifetime depression to bypass reverse causality and further assess the role of non-random selection on unobservable factors. There are expectedly no significant or substantial effects of current depression on BMI or overweight/obesity, given that BMI is a stock measure that changes relatively slowly over time. Results are also not supportive of a causal interpretation among males. However, among females, estimates indicate that past or lifetime diagnosis of major depression raises the probability of being overweight or obese by about seven percentage points. Results also suggest that this effect appears to plausibly operate through shifts in food consumption and physical activity. We estimate that this higher risk of overweight and obesity among females could potentially add about 10% (or $9.7 billion) to the estimated economic burden of depression.
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A note on the relationship between obesity and driving
Sheldon Jacobson, Douglas King & Rong Yuan
Transport Policy, forthcoming
Abstract:
Vehicle travel and obesity rates in the United States have surged in recent decades. This paper contributes to the mounting evidence of a link between them by drawing attention to a very close relationship between trends in miles driven per licensed driver and adult obesity rates six years later. It also presents evidence on why the effect might be expected to be lagged by six years. A simple model is produced, which predicts reductions in obesity rates over the next few years. If these reductions come about, the model will be seen to offer a powerful insight into the relationship between driving and obesity. If the relationship is more than coincidental, it has implications for transport policy and supports the development of a multi-pronged, interdisciplinary approach to tackle increased driving and obesity.
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Shared Norms and Their Explanation for the Social Clustering of Obesity
Daniel Hruschka et al.
American Journal of Public Health, forthcoming
Objectives: We aimed to test the hypothesized role of shared body size norms in the social contagion of body size and obesity.
Methods: Using data collected in 2009 from 101 women and 812 of their social ties in Phoenix, Arizona, we assessed the indirect effect of social norms on shared body mass index (BMI) measured in 3 different ways.
Results: We confirmed Christakis and Fowler's basic finding that BMI and obesity do indeed cluster socially, but we found that body size norms accounted for only a small portion of this effect (at most 20%) and only via 1 of the 3 pathways.
Conclusions: If shared social norms play only a minor role in the social contagion of obesity, interventions targeted at changing ideas about appropriate BMIs or body sizes may be less useful than those working more directly with behaviors, for example, by changing eating habits or transforming opportunities for and constraints on dietary intake.
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Dong Wang et al.
PLoS ONE, May 2011, e19835
Abstract:
The purpose of this cross-sectional observational study was to identify ethnic differences in body composition and obesity-related risk factors between Chinese and white males living in China. 115 Chinese and 114 white male pilots aged 28-63 years were recruited. Fasting body weight, height and blood pressure were measured following standard procedures. Whole-body and segmental body composition were measured using an 8-contact electrode bioimpedance analysis (BIA) system. Fasting serum glucose, fasting plasma total cholesterol (TC), high-density lipoprotein (HDL) cholesterol, and triglycerides (TG) were assessed using automatic biochemistry analyzer. After adjusting for age and body mass index (BMI), Chinese males had significantly higher percentage of body fat (PBF) both with respect to whole body (Chinese: 23.7%±0.2% vs. Whites: 22.4%±0.2%) and the trunk area (Chinese: 25.0%±0.3% vs. Whites: 23.2%±0.3%) compared to their white counterparts. At all BMIs, Chinese males had significantly higher fasting glucose levels (Chinese: 5.7±1.0 mmol/L vs. Whites: 5.2±1.0 mmol/L) but lower high-density lipoprotein levels (Chinese: 0.8±1.0 mmol/L vs. Whites: 1.0±1.0 mmol/L) than white males. In addition, a marginally significantly higher diastolic blood pressure was found among Chinese men than that among white men (Chinese: 80±1.0 mmHg vs. Whites: 77±1.0 mmHg). Chinese males had more body fat and a greater degree of central fat deposition pattern than that seen in white males in the present study. Furthermore, data on blood pressure, fasting glucose and blood lipids suggest that Chinese men may be more prone to obesity-related risk factors than white men.
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Mirror, Mirror on the Wall: Peer Competition, Television Influences, and Body Image Dissatisfaction
Christopher Ferguson et al.
Journal of Social and Clinical Psychology, May 2011, Pages 458-483
Abstract:
The current paper reports on two studies of body dissatisfaction with Hispanic majority samples. Both studies seek to examine the relative importance of peer and media influences on body dissatisfaction. In the first experimental study, 150 young women were randomized to watch television shows with or without thin-ideal actresses, and to be exposed to peers who either were or were not dressed to advertise sexual competitiveness. Results indicated that body dissatisfaction increased in the presence of competitive females, particularly when a desirable male was present. Television exposure did not influence body dissatisfaction. In an accompanying correlational study of 383 teenage girls, body dissatisfaction was found to relate primarily to Body Mass Index, depression, and anxiety. Television exposure did not predict body dissatisfaction, nor did peer influences. However, both competition with unfriendly girls and television exposure predicted feelings of inferiority response to other girls, although the effects for television were comparatively small.
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Eating Their Feelings: Examining Emotional Eating in At-Risk Groups in the United States
Elyria Kemp, My Bui & Sonya Grier
Journal of Consumer Policy, June 2011, Pages 211-229
Abstract:
Emotional eating affects many individuals and can lead to food overconsumption. The present research provides a theoretical foundation for examining the influence of food advertising, social norms, and related mediating influences on emotional eating. Insight offered through interviews with emotional eaters and an emotional eating conceptual model demonstrate that emotional eating is heavily influenced by food advertising, which can incite desire and ruminative thoughts about food. Additionally, emotional eaters may enlist prefactuals in the form of hedonic rationalizations to justify unhealthy eating behavior. Evidence from this research also suggests that individuals who emotionally eat may be doing so because such behavior has been learned. Finally, despite regulatory and policy efforts to create more informed consumers by providing nutrient content information on labels and packaging, emotional eaters possess little motivation to process this information. Implications for public policy and social marketing initiatives are discussed.
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Childhood Overweight: Does Quality of Parental Childcare Time Matter?
Wen You & George Davis
Journal of Family and Economic Issues, June 2011, Pages 219-232
Abstract:
This study investigates the impact of parental primary childcare time (quality time) and parental secondary childcare time (multi-tasking time) on children's overweight probability using data collected from each parent and one child aged 9-16 from 311 families in Houston MSA, US. We find that the primary childcare time is not marginally more important than the secondary childcare time and paternal childcare time is especially important for young children (age 9-11). Furthermore, if parents of overweight children adopt the time inputs of parents of healthy weight children, the predicted overweight probability decreases by ~15% on average, ceteris paribus. If either one of the parents is completely uninvolved, the overweight probability increases by ~21% on average, ceteris paribus.
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DeMarc Hickson et al.
American Journal of Public Health, forthcoming
Objectives: We examined the associations of fast food restaurant (FFR) availability with dietary intake and weight among African Americans in the southeastern United States.
Methods: We investigated cross-sectional associations of FFR availability with dietary intake and body mass index (BMI) and waist circumference in 4740 African American Jackson Heart Study participants (55.2 612.6 years, 63.3% women). We estimated FFR availability using circular buffers with differing radii centered at each participant's geocoded residential location.
Results: We observed no consistent associations between FFR availability and BMI or waist circumference. Greater FFR availability was associated with higher energy intake among men and women younger than 55 years, even after adjustment for individual socioeconomic status. For each standard deviation increase in 5-mile FFR availability, the energy intake increased by 138 kilocalories (confidence interval [CI]=70.53, 204.75) for men and 58 kilocalories (CI=8.55,105.97) for women. We observed similar associations for the 2-mile FFR availability, especially in men. FFR availability was also unexpectedly positively associated with total fiber intake.
Conclusions: FFR availability may contribute to greater energy intake in younger African Americans who are also more likely to consume fast food.
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Nineteenth century African-American and White biological living conditions in Texas
Scott Alan Carson
Social Science Journal, January 2011, Pages 234-249
Abstract:
Using a source of 19th century Texas state prison inmate records, the present study contrasts the biological living conditions of comparable 19th century African and European Americans. Average Black stature ironically increased during the antebellum period and decreased immediately after emancipation, while average White stature declined throughout the second half of the 19th century. Texas Black BMI values declined during the late 19th and early 20th centuries; however, White BMI values increased, indicating considerable 19th century biological inequality by race. Therefore, the known material inequality that existed in the 19th century American South is reinforced with biological markers.
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Selene Phillips, Lindsay Della & Steve Sohn
Journal of Health Communication, Spring 2011, Pages 416-430
Abstract:
In an exploratory analysis of several highly circulated consumer cancer magazines, the authors evaluated congruency between visual images of cancer patients and target audience risk profile. The authors assessed 413 images of cancer patients/potential patients for demographic variables such as age, gender, and ethnicity/race. They compared this profile with actual risk statistics. The images in the magazines are considerably younger, more female, and more White than what is indicated by U.S. cancer risk statistics. The authors also assessed images for visual signs of cancer testing/diagnosis and treatment. Few individuals show obvious signs of cancer treatment (e.g., head scarves, skin/nail abnormalities, thin body types). Most images feature healthier looking people, some actively engaged in construction work, bicycling, and yoga. In contrast, a scan of the editorial content showed that nearly two thirds of the articles focus on treatment issues. To explicate the implications of this imagery-text discontinuity on readers' attention and cognitive processing, the authors used constructs from information processing and social identity theories. On the basis of these models/theories, the authors provide recommendations for consumer cancer magazines, suggesting that the imagery be adjusted to reflect cancer diagnosis realities for enhanced message attention and comprehension.
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Eyes on the prize: The longitudinal benefits of goal focus on progress toward a weight loss goal
Kyle Conlon et al.
Journal of Experimental Social Psychology, July 2011, Pages 853-855
Abstract:
Past research suggests that focusing on what has not yet been accomplished (goal focus) signals a lack of progress towards one's high commitment goals and inspires greater motivation than does focusing on what has already been accomplished (accomplishment focus). The present investigation extends this research to a longitudinal, important domain by exploring the consequences of focusing on one's goals versus accomplishments when pursuing a weight loss goal. Participants were tracked over the course of a 12-week weight loss program that utilized weekly group discussions and a companion website to direct participants' focus toward their end weight loss goal or toward what they had already achieved. Goal-focused participants reported higher levels of commitment to their goal and, ultimately, lost more weight than did accomplishment-focused and no focus control participants. Accomplishment-focused participants did not differ from controls on any measure.
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Changing everyday health behaviors through descriptive norm manipulations
Jerry Burger & Martin Shelton
Social Influence, Spring 2011, Pages 69-77
Abstract:
We conducted an observational study to examine the effects of descriptive norm information on daily health behaviors. For 3 weeks, in three university campus locations, we counted the number of people who used an elevator versus stairs to go up one or two floors. Signs posted near two of the elevators during the second week stated either that most people used the stairs or that taking the stairs was a good way to get some exercise. In the location with the norm information sign, the number of individuals who used the elevator versus the stairs dropped by 46% between the first and second week. This lower rate of elevator use was also found the week after the sign had been removed. No significant change in elevator use was seen either at the location with the sign encouraging exercise or at the location with no sign. The findings are consistent with the focus theory of normative conduct and suggest avenues for improving everyday health behaviors.
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Maternal Work and Child Overweight and Obesity: The Importance of Timing
Daniel Miller
Journal of Family and Economic Issues, June 2011, Pages 204-218
Abstract:
Previous studies have found that increased work by mothers results in an increased likelihood that children are obese. Building upon this work, this study uses data from the National Longitudinal Survey of Youth-Child Supplement to investigate whether the timing of maternal work matters to this relationship. Fixed effects models found that maternal work at ages 9-11 and 12-14 was related to an increased rate of overweight during the same periods, while work at ages 6-8 resulted in a decreased rate of obesity in the same period and later at ages 9-11, a novel finding. Subgroup analyses found that effects were confined to families who were relatively low income and to children who grew up with single mothers.
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Hold the croissant! The European Union declares war on obesity
Paulette Kurzer & Alice Cooper
Journal of European Social Policy, May 2011, Pages 107-119
Abstract:
In this paper, we argue that EU institutions have demonstrated an interest in diet/nutrition for some time, but only in the last five years has obesity risen to the top of the agenda. How did the Commission and European parliament become involved in fighting obesity? It is not because national governments or societal interest groups or public health agencies pushed EU officials to reduce the body mass of European citizens. Rather, drawing on the literature on transnational policy actors, we show that the current attention to obesity is heavily influenced by WHO research reports. Moreover, the WHO's recommendations on obesity supply EU institutions with a new agenda, which in turn mobilizes pan-European groups and private sector interests. Obesity provides a further example of entrepreneurial Commission officials pursuing alliances with international institutions in order to take advantage of their scientific expertise and to carve out a new EU agenda.
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David Levitsky & Carly Pacanowski
Appetite, forthcoming
Abstract:
High-protein liquid meal replacements have proven to be effective in reducing caloric intake and body weight. Recently, substituting high fiber breakfast cereals for the more expensive high-protein drinks has been found to be equally effective to reduce weight. The following study tested the hypothesis that the mechanism responsible for the reduced intake was not the dietary composition of the meal replacement, but the controlled portion sized meals. Seventeen volunteers ate all of their meals and snacks from foods provided by the research unit from Monday to Friday for five consecutive weeks. For the first week, all participants selected their food from a buffet where each food was weighed before and after eating. For the next two weeks, half of the group selected their lunch by choosing one food from a selection of six commercially available portion controlled foods. They could eat as much as they wished at other meals or snacks. For final weeks four and five, the conditions were reversed for the two groups. Consuming the portion controlled lunches resulted in about a 250 kcal reduction in energy intake. More importantly, no sign of caloric compensation was evident across the 10 days of testing, an observation substantiated by a significant loss of body weight. The results suggest that the mere substitution of one smaller portioned meal each day is sufficient to cause reduction in daily energy intake and a significant amount of weight.
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Marleen De Moor et al.
Behavior Genetics, March 2011, Pages 211-222
Abstract:
Individual differences in adolescent exercise behavior are to a large extent explained by shared environmental factors. The aim of this study was to explore to what extent this shared environment represents effects of cultural transmission of parents to their offspring, generation specific environmental effects or assortative mating. Survey data on leisure-time exercise behavior were available from 3,525 adolescent twins and their siblings (13-18 years) and 3,138 parents from 1,736 families registered at the Netherlands Twin Registry. Data were also available from 5,471 adult twins, their siblings and spouses similar in age to the parents. Exercise participation (No/Yes, using a cut-off criterion of 4 metabolic equivalents and 60 min weekly) was based on questions on type, frequency and duration of exercise. A model to analyze dichotomous data from twins, siblings and parents including differences in variance decomposition across sex and generation was developed. Data from adult twins and their spouses were used to investigate the causes of assortative mating (correlation between spouses = 0.41, due to phenotypic assortment). The heritability of exercise in the adult generation was estimated at 42%. The shared environment for exercise behavior in adolescents mainly represents generation specific shared environmental influences that seem somewhat more important in explaining familial clustering in girls than in boys (52 versus 41%). A small effect of vertical cultural transmission was found for boys only (3%). The remaining familial clustering for exercise behavior was explained by additive genetic factors (42% in boys and 36% in girls). Future studies on adolescent exercise behavior should focus on identification of the generation specific environmental factors.
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Lesley Terry & Paul Vasey
Archives of Sexual Behavior, June 2011, Pages 639-645
Abstract:
Feederism is a fat fetish subculture in which individuals eroticize weight gain and feeding. Feeders are individuals who claim to become sexually aroused by feeding their partners and encouraging them to gain weight. Conversely, Feedees are individuals who claim to become sexually aroused by eating, being fed, and the idea or act of gaining weight. Very little is known about this population. This report describes a woman who self-identified as a Feedee. It is unclear, at present, whether female Feederism represents a unique paraphilia or a thematic variation of morphophilia or sexual masochism.