Shape Up
Maoyong Fan
American Journal of Agricultural Economics, July 2010, Pages 1165-1180
Abstract:
This article estimates the effects of food stamp benefits on obesity, overweight and body mass index of low-income women. My analysis differs from previous research in three aspects. First, we exploit a rich longitudinal dataset, the National Longitudinal Survey of Youth 1979, to distinguish between full-time and part-time participation. Second, instead of making parametric assumptions on outcomes, we employ a variety of difference-in-difference matching estimators to control for selection bias. Third, we estimate both short-term (one-year participation) and long-term (three-year participation) treatment effects. We find little evidence that food stamps are responsible for obesity in female participants.
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A Silver Lining? The Connection between Gasoline Prices and Obesity
Charles Courtemanche
Economic Inquiry, forthcoming
Abstract:
I find evidence of a negative association between gasoline prices and body weight using a fixed effects model with several robustness checks. I also show that increases in gas prices are associated with additional walking and a reduction in the frequency with which people eat at restaurants, explaining their effect on weight. My estimates imply that 8% of the rise in obesity between 1979 and 2004 can be attributed to the concurrent drop in real gas prices, and that a permanent $1 increase in gasoline prices would reduce overweight and obesity in the United States by 7% and 10%.
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Effects of Urban Sprawl On Obesity
Zhenxiang Zhao & Robert Kaestner
Journal of Health Economics, forthcoming
Abstract:
In this paper, we examine the effect of changes in population density - urban sprawl - between 1970 and 2000 on BMI and obesity of residents in metropolitan areas in the US. We address the possible endogeneity of population density by using a two-step instrumental variables approach. We exploit the plausibly exogenous variation in population density caused by the expansion of the U.S. Interstate Highway System, which largely followed the original 1947 plan for the Interstate Highway System. We find a negative association between population density and obesity, and estimates are robust across a wide range of specifications. Estimates indicate that if the average metropolitan area had not experienced the decline in the proportion of population living in dense areas over the last 30 years, the rate of obesity would have been reduced by approximately 13%.
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Drinking more water: An effective strategy for the prevention and treatment of obesity?
Brenda Davy, Elizabeth Dennis, Valisa Hedrick, Paul Estabrooks & Andrea Dietrich
Virginia Tech Working Paper, August 2010
Abstract:
The Surgeon General's Vision for a Healthy and Fit Nation (USDHHS, 2010) recommends obesity prevention initiatives which focus not only on personal behaviors and biological traits, but also on characteristics of social and physical environments which impact health. The Surgeon General's report recognizes "drinking more water" as an important factor in creating a healthy and fit nation. Yet, the physiological requirement for "adequate" water consumption is uncertain, and the biochemistry of our natural thirst mechanism may be inadequate to drive levels of fluid consumption which maintain hydration, and promote optimal health. This presentation will address these issues, and present results of the first randomized controlled intervention trial demonstrating that increased water consumption is an effective weight loss strategy. Factors which may be associated with habitual water consumption, such as body weight status, socioeconomic status, and educational level will also be presented.
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John Ayers, Richard Hofstetter, Veronica Irvin, Yoonju Song, Hae-Ryun Park, Hee-Yong Paik & Melbourne Hovell
Journal for the Scientific Study of Religion, September 2010, Pages 536-549
Abstract:
This research examines the influence of messages from religious leaders and congregants on whether Korean women are overweight or obese. Data were drawn from telephone interviews with a probability sample (N = 591) of women of Korean descent living in California. Overweight or obese prevalence was measured using World Health Organization standards for Asians (BMI > 23). Respondents reported the frequency of messages discouraging "excessive eating" or encouraging "exercise" from religious leaders and congregants during a typical month. When conditioned on leaders' messages, the frequency of congregants' messages was associated with a significantly lower probability of being overweight or obese, although messages from either in the absence of the other were unassociated with being overweight or obese. At least for Korean women, religion may help prevent obesity via religious-based social mechanisms.
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John Komlos & Marek Brabec
American Journal of Human Biology, September/October 2010, Pages 631-638
Background: The trend in the body mass index (BMI) values of the US population has not been estimated accurately because the time series data are unavailable and the focus has been on calculating period effects.
Objectives: To estimate the trend and rate of change of BMI values by birth cohorts stratified by gender and ethnicity born 1882-1986.
Methods: We use loess additive regression models to estimate age and trend effects of BMI values of US-born black and white adults measured between 1959 and 2006. We use all the National Health Examination Survey and National Health and Nutrition Examination Survey data.
Results: The increase in BMI was already underway among the birth cohorts of the early 20th century. The rate of increase was fastest among black females; for the three other groups under consideration, the rates of increase were similar. The generally persistent upward trend was punctuated by upsurges, particularly after each of the two world wars. The estimated rate of change of BMI values increased by 71% among black females between the birth cohorts 1955 and those of 1965 is indicative of the rapid increases in their weight.
Conclusions: We infer that transition to postindustrial weights was a gradual process and began considerably earlier than hitherto supposed.
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The Skinny on Success: Body Mass, Gender and Occupational Standing Across the Life Course
Christy Glass, Steven Haas & Eric Reither
Social Forces, June 2010, Pages 1777-1806
Abstract:
Several studies have analyzed the impact of obesity on occupational standing. This study extends previous research by estimating the influence of body mass on occupational attainment over three decades of the career using data from the Wisconsin Longitudinal Study. In a series of covariance structure analyses, we considered three mechanisms that may alter the career trajectories of heavy individuals: (1. employment-based discrimination, (2. educational attainment, and (3. marriage market processes. Unlike previous studies, we found limited evidence that employment-based discrimination impaired the career trajectories of either men or women. Instead, we found that heavy women received less post-secondary schooling than their thinner peers, which in turn adversely affected their occupational standing at each point in their careers.
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Dianne Neumark-Sztainer, Katherine Bauer, Sarah Friend, Peter Hannan, Mary Story & Jerica Berge
Journal of Adolescent Health, September 2010, Pages 270-276
Purpose: To learn about parent weight talk, parent dieting, and family weight-teasing in the homes of adolescent girls at risk for obesity and weight-related problems. To examine associations between these family variables and girls' weight status, body satisfaction, and disordered eating behaviors.
Methods: Data were collected at baseline from girls participating in a school-based intervention to prevent weight-related problems. Participants included 356 adolescent girls from 12 high schools. The girls' mean age was 15.8 years; 46% were overweight or obese; and more than 75% were racial/ethnic minorities.
Results: A high percentage of girls reported parent weight talk (i.e., comments about one's own weight and encouragement of daughter to diet), parent dieting, and family weight-teasing. For example, 45% of the girls reported that their mothers encouraged them to diet and 58% reported weight-teasing by family members. Weight-teasing was strongly associated with higher body mass index, body dissatisfaction, unhealthy and extreme weight control behaviors, and binge eating with loss of control in the girls. Parent weight talk, particularly by mothers, was associated with many disordered eating behaviors. Mother dieting was associated with girls' unhealthy and extreme weight control behaviors. In no instances were family weight talk and dieting variables associated with better outcomes in the girls.
Conclusions: Parent weight-related comments and dieting behaviors, and family weight-teasing, may contribute to disordered eating behaviors in adolescent girls. Health care providers can help parents provide a supportive home environment by discouraging weight-based comments, which may be intended to be helpful, but can have unintentional harmful consequences.
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Childhood Obesity, Academic Achievement, and School Expenditures
Tami Gurley-Calvez & Amy Higginbotham
Public Finance Review, September 2010, Pages 619-646
Abstract:
The authors examine whether childhood obesity affects student achievement and whether these effects differ by family income level. Although childhood obesity is a national concern, the issue is even more urgent in West Virginia where obesity rates for fifth graders are near 30 percent. Using a 2003-2007 panel of school district data, the authors find evidence that obesity negatively affects reading proficiency in high poverty districts, but obesity rates have little effect in lower poverty districts. The authors estimate that it would require a substantial increase in instructional education spending to offset the obesity effects on academic achievement in high poverty districts.
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Emily Fitzgibbons Shafer
Journal of Family Issues, September 2010, Pages 1166-1182
Abstract:
Does marriage have a causal impact on weight and the likelihood of becoming obese? Marriage is thought to have a protective influence on both men's and women's health, although via different mechanisms. Evidence in regard to marriage affecting body mass index (BMI) and the propensity to become obese, however, is mixed and often based on limited data. Even less clear is whether the effect varies by race and gender. In this article, the author uses the National Longitudinal Survey of Youth (1979), which has followed individuals for more than 20 years, and uses methods aimed at netting out selection bias to show that marriage is associated with a modest increase in BMI for all race and gender groups. Additionally, marriage is associated with an increase in the likelihood for becoming obese for African American women.
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The Trend of BMI Values of US Adults by Centiles, birth cohorts 1882-1986
John Komlos & Marek Brabec
NBER Working Paper, August 2010
Abstract:
Trends in BMI values are estimated by centiles of the US adult population by birth cohorts 1886-1986 stratified by ethnicity. The highest centile increased by some 18 to 22 units in the course of the century while the lowest ones increased by merely 1 to 3 units. Hence, the BMI distribution became increasingly right skewed as the distance between the centiles became increasingly larger. The rate of change of BMI centile curves varied considerably over time. The BMI of white men and women experienced upsurges after the two World Wars and downswings during the Great Depression and again after 1970. However, among blacks the pattern is different during the first half of the century with men's rate of increase in BMI values decreasing substantially and that of females remaining unchanged at a relatively high level until the Second World War. However, after the war the rate of change of BMI values of blacks resembled that of the whites with an accelerating phase followed by a slow down around the 1970s. In sum, the creeping nature of the obesity epidemic is evident, as the technological and lifestyle changes of the 20th century affected various segments of the population quite differently.
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Richard Dunn
American Journal of Agricultural Economics, July 2010, Pages 1149-1164
Abstract:
This paper employs an identification strategy based on county-level variation in the number of fast-food restaurants to investigate the effect of fast-food availability on weight outcomes by geographic location, gender, and race/ethnicity. The number of interstate exits in the county of residence is employed as an instrument for restaurant location. Using the 2004-2006 Behavioral Risk Factor Surveillance System and self-collected data on the number of fast-food restaurants, I find that availability does not affect weight outcomes in rural counties, but does tend to increase body mass index among females and non-Whites in medium-density counties. These results are robust to specification choices.
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Can a Statin Neutralize the Cardiovascular Risk of Unhealthy Dietary Choices?
Emily Ferenczi, Perviz Asaria, Alun Hughes, Nishi Chaturvedi & Darrel Francis
American Journal of Cardiology, 15 August 2010, Pages 587-592
Abstract:
The cardiovascular risk reduction associated with different statins for the prevention of cardiovascular disease and the cardiovascular risk increase associated with excess dietary intake of fat have been quantified. However, these relative risks have never been directly juxtaposed to determine whether an increase in relative risk by 1 activity could be neutralized by an opposing change in relative risk from a second activity. The investigators compared the increase in relative risk for cardiovascular disease associated with the total fat and trans fat content of fast foods against the relative risk decrease provided by daily statin consumption from a meta-analysis of statins in primary prevention of coronary artery disease (7 randomized controlled trials including 42,848 patients). The risk reduction associated with the daily consumption of most statins, with the exception of pravastatin, is more powerful than the risk increase caused by the daily extra fat intake associated with a 7-oz hamburger (Quarter Pounder®) with cheese and a small milkshake. In conclusion, statin therapy can neutralize the cardiovascular risk caused by harmful diet choices. In other spheres of human activity, individuals choosing risky pursuits (motorcycling, smoking, driving) are advised or compelled to use measures to minimize the risk (safety equipment, filters, seatbelts). Likewise, some individuals eat unhealthily. Routine accessibility of statins in establishments providing unhealthy food might be a rational modern means to offset the cardiovascular risk. Fast food outlets already offer free condiments to supplement meals. A free statin-containing accompaniment would offer cardiovascular benefits, opposite to the effects of equally available salt, sugar, and high-fat condiments. Although no substitute for systematic lifestyle improvements, including healthy diet, regular exercise, weight loss, and smoking cessation, complimentary statin packets would add, at little cost, 1 positive choice to a panoply of negative ones.
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The Effect of Fast Food Restaurants on Obesity and Weight Gain
Janet Currie, Stefano DellaVigna, Enrico Moretti & Vikram Pathania
American Economic Journal: Economic Policy, August 2010, Pages 32-63
Abstract:
We investigate how changes in the supply of fast food restaurants affect weight outcomes of 3 million children and 3 million pregnant women. Among ninth graders, a fast food restaurant within 0.1 miles of a school results in a 5.2 percent increase in obesity rates. Among pregnant women, a fast-food restaurant within 0.5 miles of residence results in a 1.6 percent increase in the probability of gaining over 20 kilos. The implied effects on caloric intake are one order of magnitude larger for children than for mothers, consistent with smaller travel cost for adults. Non-fast food restaurants and future fast-food restaurants are uncorrelated with weight outcomes.
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Tobacco use moderates the association between major depression and obesity
Adam Leventhal, Lavonda Mickens, Genevieve Dunton, Steve Sussman, Nathaniel Riggs & Mary Ann Pentz
Health Psychology, September 2010, Pages 521-528
Objective: Based on a maladaptive coping explanation, the relationship between major depression (MD) and obesity could be strong among nonsmokers, who may engage in unhealthy eating and sedentary behavior to cope with depression. By contrast, the MD-obesity association could be weak among smokers, who can use tobacco (instead of food or sedentary behavior) to cope with mood symptoms. This study examined smoking status and tobacco dependence as moderators of the MD-obesity link.
Design: Correlational, cross-sectional population-based survey of 41,654 U.S. adults.
Main Outcome Measures: Obesity (body mass index [BMI] ≥30 kg/m2) and quantitative BMI value.
Results: Current smoking status moderated the association between past-year MD and current obesity, as well as the link between MD and BMI value (ps ≤ .0001). MD predicted obesity and BMI among nonsmokers (ps < .0001) but did not do so in smokers (ps ≥ .10). Similar findings emerged with tobacco dependence as the moderator. Each finding persisted after accounting for demographics, psychiatric variables, and potential confounds.
Conclusion: Tobacco use characteristics appear to moderate the MD-obesity association in the U.S. population. These findings may shed light on the mechanisms linking MD and obesity and have implications for identifying which individuals may benefit most from obesity interventions that target depressive symptoms.
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Body Mass Index and Attempted Suicide: Cohort Study of 1,133,019 Swedish Men
David Batty, Elise Whitley, Mika Kivimäki, Per Tynelius & Finn Rasmussen
American Journal of Epidemiology, forthcoming
Abstract:
Associations between body mass index (BMI) and attempted (nonfatal) suicide have recently been reported. However, the few existing studies are relatively small in scale, the majority cross-sectional, and results contradictory. The authors have explored BMI-attempted suicide associations in a large cohort of 1,133,019 Swedish men born between 1950 and 1976, with BMI measured in early adulthood. During a mean follow-up of 23.9 years, a total of 18,277 (1.6%) men had at least 1 hospital admission for attempted suicide. After adjustment for confounding factors, there was a stepwise, linear decrease in attempted suicide with increasing BMI across the full BMI range (per standard deviation increase in BMI, hazard ratio = 0.93, 95% confidence interval: 0.91, 0.94). Analyses excluding men with depression at baseline were essentially identical to those based on the complete cohort. In men free from depression at baseline, controlling for subsequent depression slightly attenuated the raised risk of attempted suicide, particularly in lower weight men. This study suggests that lower weight men have an increased risk of attempted suicide and that associations may extend into the "normal" BMI range.
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Here's Looking at You: Self-Objectification, Body Image Disturbance, and Sorority Rush
Ashley Marie Rolnik, Renee Engeln-Maddox & Steven Miller
Sex Roles, July 2010, Pages 6-17
Abstract:
This study investigated the impact of sorority rush on self-objectification and body image disturbance. First-year undergraduate women either participating (n = 68) or not participating (n = 59) in sorority rush at a U.S. Midwestern university completed online surveys at four time points. It was predicted that rush participation would lead to increases in self-objectification, which in turn would lead to increases in body shame and eating disordered behavior and attitudes. Results supported predictions based on objectification theory at a single time point, but not longitudinally. Rush participants evidenced higher levels of self-objectification and eating disordered behavior at all time points. Body mass index predicted dropping out of the rush process and was negatively correlated with satisfaction with the rush process.
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Orfeu Buxton & Enrico Marcelli
Social Science & Medicine, September 2010, Pages 1027-1036
Abstract:
Research associates short (and to a lesser extent long) sleep duration with obesity, diabetes, and cardiovascular disease; and although 7-8 h of sleep seems to confer the least health risk, these findings are often based on non-representative data. We hypothesize that short sleep (<7 h) and long sleep (>8 h) are positively associated with the risk of obesity, diabetes, hypertension, and cardiovascular disease; and analyze 2004-2005 US National Health Interview Survey data (n = 56,507 observations, adults 18-85) to test this. We employ multilevel logistic regression, simultaneously controlling for individual characteristics (e.g., ethnoracial group, gender, age, education), other health behaviors (e.g., exercise, smoking), family environment (e.g., income, size, education) and geographic context (e.g., census region). Our model correctly classified at least 76% of adults on each of the outcomes studied, and sleep duration was frequently more strongly associated with these health risks than other covariates. These findings suggest a 7-8 h sleep duration directly and indirectly reduces chronic disease risk.
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Point-of-Purchase Price and Education Intervention to Reduce Consumption of Sugary Soft Drinks
Jason Block, Amitabh Chandra, Katherine McManus & Walter Willett
American Journal of Public Health, August 2010, Pages 1427-1433
Objectives: We investigated whether a price increase on regular (sugary) soft drinks and an educational intervention would reduce their sales.
Methods: We implemented a 5-phase intervention at the Brigham and Women's Hospital cafeteria in Boston, Massachusetts. After posting existing prices of regular and diet soft drinks and water during baseline, we imposed several interventions in series: a price increase of 35% on regular soft drinks, a reversion to baseline prices (washout), an educational campaign, and a combination price and educational period. We collected data from a comparison site, Beth Israel Deaconess Hospital, also in Boston, for the final 3 phases.
Results: Sales of regular soft drinks declined by 26% during the price increase phase. This reduction in sales persisted throughout the study period, with an additional decline of 18% during the combination phase compared with the washout period. Education had no independent effect on sales. Analysis of the comparison site showed no change in regular soft drink sales during the study period.
Conclusions: A price increase may be an effective policy mechanism to decrease sales of regular soda. Further multisite studies in varied populations are warranted to confirm these results.