Fat
Residential property values are associated with obesity among women in King County, WA, USA
Colin Rehm et al.
Social Science & Medicine, forthcoming
Abstract:
Studies of social determinants of weight and health in the US have typically relied on self-reported education and incomes as the two primary measures of socioeconomic status (SES). The assessed value of one's home, an important component of wealth, may be a better measure of the underlying SES construct and a better predictor of obesity. The Seattle Obesity Study (SOS), conducted in 2008-9, was a cross-sectional random digit dial telephone survey of 2001 adults in King County, Washington State, US. Participants' addresses were geo-coded and residential property values for each tax parcel were obtained from the county tax assessor's database. Prevalence ratios of obesity by property values, education, and household income were estimated separately for women and men, after adjusting for age, race/ethnicity, household size, employment status and home ownership. Among women, the inverse association between property values and obesity was very strong and independent of other SES factors. Women in the bottom quartile of property values were 3.4 times more likely to be obese than women in the top quartile. No association between property values and obesity was observed for men. The present data strengthen the evidence for a social gradient in obesity among women. Property values may represent a novel and objective measure of SES at the individual level in the US. Measures based on tax assessment data will provide a valuable resource for future health studies.
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Bisakha Sen
Journal of Policy Analysis and Management, Spring 2012, Pages 338-366
Abstract:
Obesity is epidemic in the United States, and there is an imperative need to identify policy tools that may help fight this epidemic. A recent paper in the economics literature finds an inverse relationship between gasoline prices and obesity risk - suggesting that increased gasoline prices via higher gasoline taxes may have the effect of reducing obesity prevalence. This study builds upon that paper. It utilizes cross-sectional time series data from the American Time Use Survey (ATUS) over 2003-2008, utilizes the increases that occurred in gasoline prices in this period due to Hurricane Katrina and to the global spike in gasoline prices as a "natural experiment," and explores how time spent by Americans on different forms of physical activity is associated with gasoline price levels. Economic theory suggests that higher gasoline prices may alter individual behavior both via a "substitution effect" whereby people seek alternatives to motorized transportation, and an "income effect" whereby the effect of higher gasoline prices on the disposable family budget leads people to make various adjustments to what they spend money on. The latter may lead to some increase in physical activity (for example, doing one's own yard work instead of hiring help), but may also lead to decreases in other physical activities that involve expenses, such as team sports or workouts at the gym. Thus, ultimately, the relationship between gasoline prices and physical activity must be empirically determined. Results from multivariate regression models with state and time fixed effects indicate that higher gasoline prices are associated with an overall increase of physical activity that is at least moderately energy intensive. The increases are most pronounced in periods where gasoline prices fluctuate more sharply and unexpectedly. These results appear robust to a number of model specifications. One of the major components of this increase appears to be an increase in housework that is at least moderately energy intensive - such as interior and exterior cleaning, garden, and yard work. This tentatively suggests that there is an income effect of higher gasoline prices, or a possible increase in prices of such services when gasoline prices increase. However, the increases in physical activity associated with increased gasoline prices are weaker among minorities and low socioeconomic status (SES) individuals. Hence, while a policy that increases gasoline prices via raised gasoline taxes may have benefits in terms of increasing overall physical activity levels in the United States, these benefits may not accrue to low SES individuals to the same extent as to their higher SES counterparts. This suggests that if increasing physical activity is the primary goal, then it may be more efficient to use a tax that can exert an income effect on mid-to-high SES households, such as a targeted income tax. On the other hand, if gasoline taxes are imposed to address other negative externalities of gasoline use, then these taxes may have the added benefit of increasing physical activity at least among some segments of U.S. society.
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Fast Food Prices, Obesity, and the Minimum Wage
Chad Cotti & Nathan Tefft
Economics & Human Biology, forthcoming
Abstract:
Recent proposals argue that a fast food tax may be an effective policy lever for reducing population weight. Although there is growing evidence for a negative association between fast food prices and weight among adolescents, less is known about adults. That any measured relationship to date is causal is unclear because there has been no attempt to separate variation in prices on the demand side from that on the supply side. We argue that the minimum wage is an exogenous source of variation in fast food prices, conditional on income and employment. In two-stage least-squares analyses, we find little evidence that fast food price changes affect adult BMI or obesity prevalence. Results are robust to including controls for area and time fixed effects, area time trends, demographic characteristics, substitute prices, numbers of establishments and employment in related industries, and other potentially related factors.
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Euna Han, Lisa Powell & Zeynep Isgor
Social Science & Medicine, June 2012, Pages 1874-1881
Abstract:
We explored the extent to which economic contextual factors moderated the association of Supplemental Nutrition Assistance Program (SNAP) participation with body mass index (BMI) among low-income adults whose family income (adjusted for family size) is less than 130% of the federal poverty guideline. We drew on individual-level data from the Panel Study of Income Dynamics in the United States, including three waves of data in 1999, 2001, and 2003. Economic contextual data were drawn from the American Chamber of Commerce Researchers Association for food prices and Dun & Bradstreet for food outlet measures. In addition to cross-sectional estimation, a longitudinal individual fixed effects model was used to control for permanent unobserved individual heterogeneity. Our study found a statistically significant joint moderating effect of the economic contextual factors in longitudinal individual fixed effects model for both women (BMI only) and men (both BMI and obesity). For both women and men, SNAP participants' BMI was statistically significantly lower if they faced increased numbers of available supermarkets/grocery stores in the longitudinal model. A simulated 20% reduction in the price of fruits and vegetables resulted in a larger decrease in BMI among SNAP participants than non-participants for women and men, whereas a simulated 20% increase in the availability of supermarkets and grocery stores resulted in a statistically significant difference in the change in BMI by SNAP participation for women but not for men. Policies related to economic contextual factors, such as subsidies for fruits and vegetables or those that would improve access to supermarkets and grocery stores may enhance the relationship between SNAP participation and body mass outcomes among food assistance program participants.
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Dietary Behaviors of a Racially and Ethnically Diverse Sample of Overweight and Obese Californians
Dara Sorkin & John Billimek
Health Education & Behavior, forthcoming
Objectives: To examine racial/ethnic differences in the dietary behaviors of overweight or obese adults using the 2007 California Health Interview Survey.
Method: Data were obtained from the 2007 California Health Interview Survey, a population-based sample of noninstitutionalized adults in California. The sample included 26,721 adults aged 18 years and older whose body mass index status indicated that they were overweight or obese (body mass index ≥ 25), with 19,264 non-Hispanic White; 1,749 African American/Black; 1,616 Asian/Pacific Islander; and 4,092 Latino respondents. Respondents were compared with regard to consumption of five categories of food: fruits, vegetables, French fries, soft drinks, and fast-food. Multivariable regression analyses were conducted to examine racial/ethnic differences in dietary behaviors, with and without adjustment for age, gender, nativity, marital status, education, income, and food insecurity.
Results: The findings suggested there were significant racial/ethnic differences in food preferences and that English proficiency, in part, explained some of these differences. Overweight/obese African American/Black respondents reported eating fruit (aBeta = -0.73, [95% confidence interval = -1.29, -0.17]) and vegetables (aBeta = -0.71 [-1.18, -0.24]) fewer times per day and fast-food (aBeta = 0.21, [0.04, 0.38]) more times per day compared with their non-Hispanic White counterparts. Irrespective of language proficiency, Asian/Pacific Islanders reported eating significantly less fruit compared with non-Hispanic Whites. Limited English proficient (LEP) Asian/Pacific Islanders were found to eat vegetables (aBeta = 1.41, [0.47, 2.63]) more times per day than non-Hispanic Whites, in contrast to English proficient Asian/Pacific Islanders who were found to eat vegetables (aBeta = -0.64, [-1.11, -0.18]) fewer times per day compared with non-Hispanic Whites. Both LEP and English proficient Latinos ate vegetables less often and drank soft drinks and ate fast-food more often than non-Hispanic Whites.
Conclusions: Efforts to intervene with individuals who are overweight or obese must include culturally and linguistically tailored interventions that consider how individuals' dietary behaviors are influenced by their racial/ethnic backgrounds.
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Dollars and pounds: The impact of family income on childhood weight
Y.F. Chia
Applied Economics, Spring 2012, Pages 1931-1941
Abstract:
This article examines the impact of family income on childhood weight status for children in the United States using matched mother-child data from the National Longitudinal Survey of Youth (NLSY 79). Instrumental variable (IV) models, family Fixed Effects (FE) models and family Fixed Effects IV (FEIV) models are estimated in order to control for causality. The results suggest that although the prevalence of childhood obesity is higher in low-income families in the sample, family income might be acting primarily as a proxy for other unobserved characteristics that determine the child's weight status rather having a major direct causative role in determining the child's weight status.
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Health Investment Decisions in Response to Diabetes Information in Older Americans
Alexander Slade
Journal of Health Economics, forthcoming
Abstract:
Diabetes is a very common and serious chronic disease, and one of the fastest growing disease burdens in the United States. Further, health behaviors, such as exercise, smoking, drinking, as well as weight status, are instrumental to diabetes management and the reduction of its medical consequences. I use nine waves of the Health and Retirement Study to model the role of a recent diabetes diagnosis and medication on present and subsequent weight status, exercise, drinking and smoking activity. I estimate several non-linear dynamic population average probit models. Results suggest that compared to non-diagnosed individuals at risk for high blood sugar, diagnosed diabetics respond initially in terms of increasing exercise, losing weight, and curbing smoking and drinking behavior, but the effect diminishes after diagnosis. I also find evidence of recidivism in these outcomes, especially weight status and physical activity, suggesting that some behavioral responses to diabetes may be short-lived.
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Andrew Rundle et al.
American Journal of Epidemiology, forthcoming
Abstract:
There are concerns that prenatal exposure to endocrine-disrupting chemicals increases children's risk of obesity. African-American and Hispanic children born in the Bronx or Northern Manhattan, New York (1998-2006), whose mothers underwent personal air monitoring for polycyclic aromatic hydrocarbon (PAH) exposure during pregnancy, were followed up to ages 5 (n = 422) and 7 (n = 341) years. At age 5 years, 21% of the children were obese, as were 25% of those followed to age 7 years. After adjustment for child's sex, age at measurement, ethnicity, and birth weight and maternal receipt of public assistance and prepregnancy obesity, higher prenatal PAH exposures were significantly associated with higher childhood body size. In adjusted analyses, compared with children of mothers in the lowest tertile of PAH exposure, children of mothers in the highest exposure tertile had a 0.39-unit higher body mass index z score (95% confidence interval (CI): 0.08, 0.70) and a relative risk of 1.79 (95% CI: 1.09, 2.96) for obesity at age 5 years, and they had a 0.30-unit higher body mass index z score (95% CI: 0.01, 0.59), a 1.93-unit higher percentage of body fat (95% CI: 0.33, 3.54), and a relative risk of 2.26 (95% CI: 1.28, 4.00) for obesity at age 7 years. The data indicate that prenatal exposure to PAHs is associated with obesity in childhood.
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Distinctive Biological Correlates of Positive Psychological Well-Being in Older Men and Women
Andrew Steptoe et al.
Psychosomatic Medicine, forthcoming
Objective: Positive psychological well-being is associated with reduced risk of chronic illnesses. Biological risk factors may contribute to these effects, although sex differences may be present. Two aspects of well-being can be distinguished: affective well-being (happiness and pleasure) and eudaemonia (sense of autonomy and purposeful engagement with life). We evaluated relationships between both affective and eudaemonic well-being and biological measures in a large sample of older people.
Methods: This cross-sectional study analyzed the English Longitudinal Study of Ageing, a nationally representative cohort aged 50 years or older. In this study, 7795 participants completed positive well-being and depressive symptom measures. Waist circumference, dehydroepiandosterone sulfate, C-reactive protein, fibrinogen, high-density lipoprotein cholesterol, plasma triglycerides, and peak expiratory flow were assessed.
Results: In men, affective well-being was associated with smaller waist circumference (B = -0.206, p < .001) and greater levels of dehydroepiandosterone sulfate (B = 0.072, p = .003). Affective well-being in women was related to lower concentrations of inflammatory markers (C-reactive protein and fibrinogen, B = -0.242 and -0.024, respectively, p < .001) and greater high-density lipoprotein cholesterol (B = 0.011, p = .017). Both men and women showed associations between well-being and lower levels of plasma triglycerides (B = -0.032, p < .001) and better lung function (B = 3.594, p < .001). Associations were independent of age, marital status, socioeconomic circumstances, body mass, smoking, limiting long-standing illnesses, health indicators, and depressive symptoms. Similar results were obtained for eudaemonic well-being.
Conclusions: Positive psychological well-being has biological correlates that may be health protective, with distinctive patterns for men and women.
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Genetic Influences on Adolescent Eating Habits
Kevin Beaver et al.
Health Education & Behavior, April 2012, Pages 142-151
Abstract:
Behavioral genetic research shows that variation in eating habits and food consumption is due to genetic and environmental factors. The current study extends this line of research by examining the genetic contribution to adolescent eating habits. Analysis of sibling pairs drawn from the National Longitudinal Study of Adolescent Health (Add Health) revealed significant genetic influences on variance in an unhealthy eating habits scale (h 2 = .42), a healthy eating habits scale (h 2 = .51), the number of meals eaten at a fast-food restaurant (h 2 = .33), and the total number of meals eaten per week (h 2 = .26). Most of the remaining variance was due to nonshared environmental factors. Additional analyses conducted separately for males and females revealed a similar pattern of findings. The authors note the limitations of the study and offer suggestions for future research.
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Jonathan Wells et al.
Social Science & Medicine, forthcoming
Abstract:
Obesity is widely assumed to be associated with economic affluence; it has therefore been assumed to become more common with economic development. However, obesity has also been associated with poverty. These contrary findings highlight the need for an examination of the contribution of social and economic factors to the global distribution of obesity. Males and females may be differently exposed to social and economic inequality, however few studies have considered possible gender differences in the association between socio-economic indices and obesity prevalence. We analysed between-country associations between obesity prevalence and three social or economic indices: per capita gross domestic product (GDP), the Gini index of national wealth inequality, and the Gender Inequality Index (GII). We considered the genders separately, the gender-average, and also the gender-difference (female excess) in obesity prevalence. Across 68 countries listing sample size, there were 3 obese women for every 2 obese men. Within populations, obesity prevalence in males and females was strongly correlated (r = 0.74), however, only 17% of the female excess prevalence was accounted for by the gender-average prevalence. In both genders, there was a positive association between obesity prevalence and GDP that attenuated at higher GDP levels, with this association weaker in females than males. Adjusting for GDP, both the Gini index and GII were associated with excess female obesity. These analyses highlight significant gender differences in the global distribution of obesity, and a gender-difference in the association of obesity prevalence with socio-economic factors. The magnitude of female excess obesity is not constant across populations, and is greater in countries characterised by gender inequality and lower GDP. These findings indicate that improving women's status may be a key area for addressing the global obesity epidemic in women over the long term, with potential benefits for the women themselves and for their offspring.
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Fat Talk Among College Women is Both Contagious and Harmful
Rachel Hannah Salk & Renee Engeln-Maddox
Sex Roles, May 2012, Pages 636-645
Abstract:
Fat talk is a social phenomenon during which women speak negatively with each other about the size/shape of their bodies (Nichter and Vuckovich 1994). In this study, exposure to fat talk from peers was experimentally manipulated to determine the effect of hearing fat talk on a woman's own likelihood of engaging in fat talk and on state body dissatisfaction, guilt, and sadness. Undergraduate women (n = 87; all of a healthy weight) from a Midwestern university in the United States participated in a study ostensibly about discussing magazine advertisements. Two female confederates were present for the discussion. While discussing an advertisement featuring an attractive and thin female model, participants either heard both confederates engage in fat talk, neither confederate engage in fat talk, or the first engage in fat talk and the second challenge the fat talk. Hearing a confederate fat talk made the participants more likely to fat talk themselves (especially if the fat talk went unchallenged) and increased participants' self-reported state body dissatisfaction and guilt. Participants who engaged in fat talk reported higher levels of self-reported state body dissatisfaction and guilt, compared to participants who did not engage in fat talk (even when controlling for pre-existing trait body dissatisfaction). Participant fat talk mediated the effect of condition on both state body dissatisfaction and guilt. Additionally, correlational analyses revealed that participants with higher levels of trait body dissatisfaction (assessed at a pre-test) were more likely to engage in fat talk (regardless of condition).
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Deborah Carr & Karen Jaffe
Economics & Human Biology, forthcoming
Abstract:
We use quantitative and qualitative data to explore the psychological impact of weight change among American adults. Using data from the Midlife Development in the United States (MIDUS) study, a survey of more than 3,000 adults ages 25 to 74 in 1995, we contrast underweight, normal weight, overweight, obese I, and obese II/III persons along five psychosocial outcomes: positive mood, negative mood, perceived interpersonal discrimination, self-acceptance, and self-satisfaction. We further assess whether these relationships are contingent upon one's body mass index (BMI) at age 21. We find a strong inverse association between adult BMI and each of the five outcomes, reflecting the stigma associated with high body weight. However, overweight adults who were also overweight at age 21 are more likely than persons who were previously slender to say they were "very satisfied" with themselves. Results from 40 in-depth semi-structured interviews reveal similarly that persons who were persistently overweight or obese accept their weight as part of their identity, whereas those who experienced substantial weight increases (or decreases) struggle between two identities: the weight they actually are, and the weight that they believe exemplifies who they are. We discuss implications for stigma theory, and the ways that stigma exits and entries affect psychological well-being.
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Maternal Metabolic Conditions and Risk for Autism and Other Neurodevelopmental Disorders
Paula Krakowiak et al.
Pediatrics, forthcoming
Objective: We examined whether metabolic conditions (MCs) during pregnancy (diabetes, hypertension, and obesity) are associated with autism spectrum disorder (ASD), developmental delays (DD), or impairments in specific domains of development in the offspring.
Methods: Children aged 2 to 5 years (517 ASD, 172 DD, and 315 controls) were enrolled in the CHARGE (Childhood Autism Risks from Genetics and the Environment) study, a population-based, case-control investigation between January 2003 and June 2010. Eligible children were born in California, had parents who spoke English or Spanish, and were living with a biological parent in selected regions of California. Children's diagnoses were confirmed by using standardized assessments. Information regarding maternal conditions was ascertained from medical records or structured interview with the mother.
Results: All MCs were more prevalent among case mothers compared with controls. Collectively, these conditions were associated with a higher likelihood of ASD and DD relative to controls (odds ratio: 1.61 [95% confidence interval: 1.10-2.37; odds ratio: 2.35 [95% confidence interval: 1.43-3.88], respectively). Among ASD cases, children of women with diabetes had Mullen Scales of Early Learning (MSEL) expressive language scores 0.4 SD lower than children of mothers without MCs (P < .01). Among children without ASD, those exposed to any MC scored lower on all MSEL and Vineland Adaptive Behavior Scales (VABS) subscales and composites by at least 0.4 SD (P < .01 for each subscale/composite).
Conclusions: Maternal MCs may be broadly associated with neurodevelopmental problems in children. With obesity rising steadily, these results appear to raise serious public health concerns.
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Åsa Ljungvall & Frederick Zimmerman
Social Science & Medicine, forthcoming
Abstract:
Increasing obesity rates and corresponding public health problems are well-known, and disparities across socioeconomic groups are frequently reported. However, the literature is less clear on whether the increasing trends are specific to certain socioeconomic groups and whether disparities in obesity are increasing or decreasing over time. This knowledge sheds light on the understanding of the driving forces to the ongoing worldwide increases in obesity and body-mass index and gives guidance to plausible interventions aiming at reverting weights back to healthy levels. The purpose of this study is to explore long-term time trends and socioeconomic disparities in body-mass index and obesity among U.S. adults. Individual level data from ten cycles of the National Health and Nutrition Examination Survey between 1960 and 2008 are used to estimate adjusted time trends in the probabilities of obesity and severe obesity and in measured body-mass index for three racial/ethnical groups, for three educational groups, and for four levels of income, stratified by gender. Time trends in the probabilities of obesity and severe obesity are estimated by linear probability models, and trends at the 15th, 50th and 85th percentiles of the adjusted body-mass index distribution are estimated by quantile regression. Divergent time trends for the different socioeconomic groups are estimated by interaction terms between socioeconomic status and year. The results show that, with some exceptions, increases in both obesity, severe obesity and body-mass index are similar across the different racial/ethnic, educational and income groups. We conclude that the increase in body-mass index and obesity in the United States is a true epidemic, whose signal hallmark is to have affected an entire society. Accordingly, a whole-society approach is likely to be required if the increasing trends are to be reversed.
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The Influence of Media Characters on Children's Food Choices
Jennifer Kotler, Jennifer Schiffman & Katherine Hanson
Journal of Health Communication, forthcoming
Abstract:
Two experiments were conducted to assess the role of media characters in influencing children's food choices; the first focused on children's self-reported preference, whereas the second focused on actual choice. The results of the experiments suggest that popular characters can make a difference in encouraging children to select one food over another. In the first experiment, children were more likely to indicate a preference for one food over another when one was associated with characters that they liked and with whom they were familiar. This effect was particularly strong when a sugary or salty snack branded by a favored character was competing with a healthier option branded by an unknown character or no character. Alternatively, when children were asked to choose between a healthy food and a sugary or salty snack, branding of the healthy food with a favored character did not significantly change appeal of that healthy snack. However, when foods within the same category (i.e., 2 vegetables, 2 fruits, or 2 grains) were asked to compete against each other, character branding strongly influenced children's food choice. Findings from the second experiment suggest that children are more willing to try more pieces of a healthy food if a favored character, in comparison with an unknown character, is promoting that food.
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Abigail Mandel & Paul Breslin
Journal of Nutrition, 1 May 2012, Pages 853-858
Abstract:
In the current study, we determined whether increased digestion of starch by high salivary amylase concentrations predicted postprandial blood glucose following starch ingestion. Healthy, nonobese individuals were prescreened for salivary amylase activity and classified as high (HA) or low amylase (LA) if their activity levels per minute fell 1 SD higher or lower than the group mean, respectively. Fasting HA (n = 7) and LA (n = 7) individuals participated in 2 sessions during which they ingested either a starch (experimental) or glucose solution (control) on separate days. Blood samples were collected before, during, and after the participants drank each solution. The samples were analyzed for plasma glucose and insulin concentrations as well as diploid AMY1 gene copy number. HA individuals had significantly more AMY1 gene copies within their genomes than did the LA individuals. We found that following starch ingestion, HA individuals had significantly lower postprandial blood glucose concentrations at 45, 60, and 75 min, as well as significantly lower AUC and peak blood glucose concentrations than the LA individuals. Plasma insulin concentrations in the HA group were significantly higher than baseline early in the testing session, whereas insulin concentrations in the LA group did not increase at this time. Following ingestion of the glucose solution, however, blood glucose and insulin concentrations did not differ between the groups. These observations are interpreted to suggest that HA individuals may be better adapted to ingest starches, whereas LA individuals may be at greater risk for insulin resistance and diabetes if chronically ingesting starch-rich diets.
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Adam Ameur et al.
American Journal of Human Genetics, forthcoming
Abstract:
Omega-3 and omega-6 long-chain polyunsaturated fatty acids (LC-PUFAs) are essential for the development and function of the human brain. They can be obtained directly from food, e.g., fish, or synthesized from precursor molecules found in vegetable oils. To determine the importance of genetic variability to fatty-acid biosynthesis, we studied FADS1 and FADS2, which encode rate-limiting enzymes for fatty-acid conversion. We performed genome-wide genotyping (n = 5,652 individuals) and targeted resequencing (n = 960 individuals) of the FADS region in five European population cohorts. We also analyzed available genomic data from human populations, archaic hominins, and more distant primates. Our results show that present-day humans have two common FADS haplotypes-defined by 28 closely linked SNPs across 38.9 kb-that differ dramatically in their ability to generate LC-PUFAs. No independent effects on FADS activity were seen for rare SNPs detected by targeted resequencing. The more efficient, evolutionarily derived haplotype appeared after the lineage split leading to modern humans and Neanderthals and shows evidence of positive selection. This human-specific haplotype increases the efficiency of synthesizing essential long-chain fatty acids from precursors and thereby might have provided an advantage in environments with limited access to dietary LC-PUFAs. In the modern world, this haplotype has been associated with lifestyle-related diseases, such as coronary artery disease.
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Brian Saelens et al.
American Journal of Preventive Medicine, May 2012, Pages e57-e64
Background: Identifying neighborhood environment attributes related to childhood obesity can inform environmental changes for obesity prevention.
Purpose: To evaluate child and parent weight status across neighborhoods in King County (Seattle metropolitan area) and San Diego County differing in GIS-defıned physical activity environment (PAE) and nutrition environment (NE) characteristics.
Methods: Neighborhoods were selected to represent high (favorable) versus low (unfavorable) on the two measures, forming four neighborhood types (low on both measures, low PAE/high NE, high PAE/low NE, and high on both measures). Weight and height of children aged 6-11 years and one parent (n 730) from selected neighborhoods were assessed in 2007-2009. Differences in child and parent overweight and obesity by neighborhood type were examined, adjusting for neighborhood-, family-, and individual-level demographics.
Results: Children from neighborhoods high on both environment measures were less likely to be obese (7.7% vs 15.9%, OR 0.44, p 0.02) and marginally less likely to be overweight (23.7% vs 31.7%, OR 0.67, p 0.08) than children from neighborhoods low on both measures. In models adjusted for parent weight status and demographic factors, neighborhood environment type remained related to child obesity (high vs low on both measures, OR 0.41, p 0.03). Parents in neighborhoods high on both measures (versus low on both) were marginally less likely to be obese (20.1% vs 27.7%, OR 0.66, p 0.08), although parent overweight did not differ by neighborhood environment. The lower odds of parent obesity in neighborhoods with environments supportive of physical activity and healthy eating remained in models adjusted for demographics (high vs low on the environment measures, OR 0.57, p 0.053).
Conclusions: Findings support the proposed GIS-based defınitions of obesogenic neighborhoods for children and parents that consider both physical activity and nutrition environment features.
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Sedentary Behaviors of Adults in Relation to Neighborhood Walkability and Income
Justine Kozo et al.
Health Psychology, forthcoming
Objective: Sedentary (sitting) time is a newly identified risk factor for obesity and chronic diseases, which is behaviorally and physiologically distinct from lack of physical activity. To inform public health approaches to influencing sedentary behaviors, an understanding of correlates is required.
Methods: Participants were 2,199 adults aged 20-66 years living in King County/Seattle, WA, and Baltimore, MD, regions, recruited from neighborhoods high or low on a "walkability index" (derived from objective built environment indicators) and having high or low median incomes. Cross-sectional associations of walkability and income with total sedentary time (measured by accelerometers and by self-report) and with self-reported time in seven specific sitting-related behaviors were examined.
Results: Neighborhood walkability and income were unrelated to measures of total sitting time. Lower neighborhood walkability was significantly associated with more driving time (difference of 18.2 min/day, p < .001) and more self-reported TV viewing (difference of 14.5 min/day, p < .001). Residents of higher income neighborhoods reported more computer/Internet and reading time, and they had more objectively measured sedentary time.
Conclusions: Neighborhood walkability was not related to total sedentary time but was related to two specific sedentary behaviors associated with risk for obesity-driving time and TV viewing time. Future research could examine how these prevalent and often prolonged sedentary behaviors mediate relationships between neighborhood walkability and overweight/obesity. Initiatives to reduce chronic disease risk among residents of both higher-and lower-income low-walkable neighborhoods should include a focus on reducing TV viewing time and other sedentary behaviors and enacting policies that can lead to the development or redevelopment of more-walkable neighborhoods.
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Marsha Dowda et al.
Journal of Adolescent Health, May 2012, Pages 497-502
Purpose: To investigate the relationship between proximity to commercial physical activity (PA) facilities and cardiorespiratory fitness of 12th grade girls.
Methods: Adolescent girls (n = 786, 60% African American, mean age = 17.6 ± .6 years) performed a submaximal fitness test (Physical Work Capacity 170 test). Commercial PA facilities were mapped and counted within a .75-mile street-network buffer around girls' homes using Geographic Information Systems. Sedentary activities and vigorous physical activity (≥6 metabolic equivalents) were determined by the average number of 30-minute blocks reported per day on the 3-Day Physical Activity Recall. Mixed model regressions were calculated using school as a random variable.
Results: Girls had higher weight-relative Physical Work Capacity 170 test scores if there was a commercial PA facility (n = 186, 12.4 ± 4.2 kg m/min/kg) within a .75-mile street-network buffer of home as compared with girls without a nearby facility (n = 600, 11.2 ± 3.6 kg m/min/kg). After adjusting for demographic variables, sports participation, sedentary behaviors, and vigorous physical activity, having one or more commercial PA facilities within a .75-mile street-network buffer of homes was significantly related to cardiorespiratory fitness.
Conclusions: Both with and without adjustment for covariates, the presence of a commercial PA facility within a .75-mile street-network buffer of a girl's home was associated with higher cardiorespiratory fitness.
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Socioeconomic status, stature, and obesity in women: 20-year trends in urban Colombia
Kathryn Olszowy et al.
American Journal of Human Biology, forthcoming
Objectives: Ongoing social and economic changes in developing countries are associated with increases in body size, and most notably increases in the prevalence of obesity. The social patterning of these changes in terms of socioeconomic status (SES) is not well documented. The aim of this study was to assess the changes in stature, body mass index (BMI) and fatness in adult women in urban Cali, Colombia between 1988-1989 and 2007-2008.
Methods: We compared the results of anthropometric surveys completed in 1988-1989 and 2007-2008 of nonpregnant, nonlactating women, 18-44 years of age. Samples in both studies were stratified by SES. We calculated age-standardized prevalence rates to assess time trends in obesity. Body fatness was assessed by skinfold thicknesses.
Results: Stature increased in all SES groups and remained positively associated with SES. BMI increased only in the lower SES group, from 24.4 to 25.9 kg/m2 and remained negatively associated with SES. The age-standardized prevalence of obesity increased from 7.9 to 17.0% in the lower SES group, but only from 4.5 to 8.2% in the middle SES group, and was unchanged in the upper SES group. Body fatness increased in all SES groups, but only in the upper body.
Conclusion: The increased stature in all SES groups is indicative of general improvements in socioeconomic conditions. The increased prevalence of obesity in the lower SES groups is in keeping with the findings in other middle-income developing countries.
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Min Jung Ko & Mi Kyung Kim
International Journal of Epidemiology, forthcoming
Background: Unlike the older birth cohort (1943-65), the younger birth cohort (1966-79) has enjoyed much improved standards with dramatic developments in Korea. This article investigated the relationship between socio-economic position (SEP) and risk of high blood glucose, including impaired fasting glucose (IFG) and type 2 diabetes mellitus (T2D) by birth cohort.
Methods: Of the 11 830 persons, 9792 persons aged 30-64 years participated in National Health and Nutrition Examination Surveys. We categorized four SEP groups based on education level in childhood and adulthood within two birth cohorts. High blood glucose included IFG (n = 2594) and T2D (n = 738). Odds ratio (OR) and 95% confidence interval (CI) were estimated by logistic regression.
Results: There was a significantly higher risk of high blood glucose in the younger cohort than in the older cohort. In the younger cohort, the ORs for males of declining SEP and of stable low SEP were OR: 1.50 (95% CI 1.12-2.00) and OR: 1.45 (95% CI 1.08-1.93), respectively. After adjustments, corresponding ORs were 1.47 (95% CI 1.09-1.98) and 1.54 (95% CI 1.14-2.08), respectively. In younger women, the corresponding ORs were 1.68 (95% CI 1.17-2.41) and 1.87 (95% CI 1.30-2.69), respectively; however, obesity attenuated the former relationship. For women in the older cohort, this inverse relationship was found only among those with a stable low SEP (OR 1.31, 95% CI 1.04-1.66); no significance was found after adjustments. There was no significant inverse relationship in the older cohort for men.
Conclusions: The relationship between lower SEP and elevated risk of high blood glucose was stronger in the younger birth cohort, and obesity attenuated this inverse relationship in women only.