Round numbers
Has Increased Body Weight Made Driving Safer?
Richard Dunn & Nathan Tefft
Health Economics, November 2014, Pages 1374–1389
Abstract:
We develop a model of alcohol consumption that incorporates the negative biological relationship between body mass and inebriation conditional on total alcohol consumption. Our model predicts that the elasticity of inebriation with respect to weight is equal to the own-price elasticity of alcohol, consistent with body mass increasing the effective price of inebriation. Given that alcohol is generally considered price inelastic, this result implies that as individuals gain weight, they consume more alcohol but become less inebriated. We test this prediction and find that driver blood alcohol content (BAC) is negatively associated with driver weight. In fatal accidents with driver BAC above 0.10, the driver was 7.8 percentage points less likely to be obese than drivers in fatal accidents that did not involve alcohol. This relationship is not explained by driver attributes (age and sex), driver behaviors (speed and seatbelt use), vehicle attributes (weight class, model year, and number of occupants), or accident context (county of accident, time of day, and day of week).
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In good company. The effect of an eating companion's appearance on food intake
Mitsuru Shimizu, Katie Hancock & Brian Wansink
Appetite, December 2014, Pages 263–268
Abstract:
The purpose of this study was to examine whether or not the presence of an overweight eating companion influences healthy and unhealthy eating behavior, and to determine if the effect is moderated by how the companion serves himself or herself. A professional actress either wore an overweight prosthesis (i.e., “fatsuit”) or did not wear one, and served herself either healthily (i.e., a small amount of pasta and a large amount of salad) or unhealthily (i.e., a large amount of pasta and a small amount of salad) for lunch. After observing her, male and female participants were asked to serve themselves pasta and salad to eat. Results demonstrated that regardless of how the confederate served, participants served and ate a larger amount of pasta when she was wearing the prosthesis than when she was not. In addition, when the confederate served herself healthily, participants served and ate a smaller amount of salad when she was wearing the prosthesis than when she was not. Consistent with the “lower health commitment” hypothesis, these results demonstrated that people may eat larger portions of unhealthy food and smaller portions of healthy food when eating with an overweight person, probably because the health commitment goal is less activated. More generally, this study provides evidence that the body type of an eating companion, as well as whether she serves herself healthily or unhealthily, influences the quantity of food intake.
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Cheryl Armstead et al.
Journal of Black Psychology, October 2014, Pages 424-450
Abstract:
This study describes the relative influence of facial skin color, lifetime exposure to racial discrimination, chronic stress, and traditional prehypertension risk factors (family history of hypertension and age) on resting blood pressure and body mass index (BMI) among 196 southern African American (AA) female undergraduate students. Stepwise regression analyses indicated that skin color was the strongest predictor of systolic blood pressure (SBP), diastolic blood pressure (DBP), and BMI. Skin color, chronic stress, and family history of hypertension predicted 53% of the SBP variance. Skin color, chronic stress, and family history of hypertension predicted 30.2% of the DBP variance. Racism and age were not significant predictors of SBP or DBP. Of the variance in BMI, 33% was predicted by skin color, chronic stress, and racism. Age and family history of hypertension were not predictors of BMI. The current study provides evidence of the relationship of skin color and chronic stress to blood pressure among young southern AA women. The study identifies an important relationship between increased racial stress exposure and heavier BMIs, a predictor of prehypertensive risk.
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Body Size Perception Among African American Women
Elizabeth Lynch & John Kane
Journal of Nutrition Education and Behavior, September–October 2014, Pages 412–417
Objective: To assess body size perception among African American women using cultural definitions of body size terms.
Methods: Sixty-nine African American women classified Body Image Scale figures as overweight, obese, and too fat, and independently selected the figure they considered closest to their current body size.
Results: Body size classifications of figures did not vary by participant weight status. Overweight figures were not considered too fat. For 86% of overweight (body mass index [BMI], 25–29.9) women and 40% of obese (BMI > 30) women, the self figure was not defined as overweight, obese, or too fat. Among participants with BMI ≥ 35, 65% did not classify their self figure as obese and 29% did not classify their self figure as overweight.
Conclusions and Implications: The difference between cultural (folk) and medical definitions of body size terms may serve as a barrier to effective communication between patients and providers about health effects of excess adiposity.
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Whitney Robinson et al.
Obesity, forthcoming
Objectives: Since the 1980s, older, low-educated White women experienced an unprecedented decrease in life expectancy. We investigated whether a similar phenomenon was evident among younger women for obesity.
Methods: Using the National Health and Nutrition Examination Survey, age-adjusted changes were estimated in the prevalence of overall and abdominal obesity (BMI ≥ 30 kg/m2, waist circumference > 88 cm) between 1988-1994 and 2003-2010 among non-Hispanic White women aged 25-44 years, stratified by educational attainment (<high school (HS), HS, some college, college degree). To address bias from secular increases in educational attainment, White women's changes in obesity prevalence were compared to changes among similarly educated Black women.
Results: Relative increases in overall obesity were disproportionately larger for low-educated (<HS) compared to college-educated White women: 12.3 (95% CI: 3.1, 21.5) percentage points (ppts). For overall and abdominal obesity, general trends indicated dissimilar racial differences by educational attainment. For instance, overall obesity increased more in Blacks than Whites among college-educated (9.9 ppts) but not low-educated (−2.5 ppts) women.
Conclusions: Contemporary young, low-educated White women showed indications of disproportionate worsening of overall obesity prevalence compared to more educated White and similarly educated Black women. Low education levels are more powerful indicators of obesity risk among contemporary White women than 30 years ago.
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Neighborhood Influences on Girls’ Obesity Risk Across the Transition to Adolescence
Lindsay Hoyt et al.
Pediatrics, forthcoming
Background and objectives: The neighborhoods in which children live, play, and eat provide an environmental context that may influence obesity risk and ameliorate or exacerbate health disparities. The current study examines whether neighborhood characteristics predict obesity in a prospective cohort of girls.
Methods: Participants were 174 girls (aged 8–10 years at baseline), a subset from the Cohort Study of Young Girls’ Nutrition, Environment, and Transitions. Trained observers completed street audits within a 0.25-mile radius around each girl’s residence. Four scales (food and service retail, recreation, walkability, and physical disorder) were created from 40 observed neighborhood features. BMI was calculated from clinically measured height and weight. Obesity was defined as BMI-for-age ≥95%. Logistic regression models using generalized estimating equations were used to examine neighborhood influences on obesity risk over 4 years of follow-up, controlling for race/ethnicity, pubertal status, and baseline BMI. Fully adjusted models also controlled for household income, parent education, and a census tract measure of neighborhood socioeconomic status.
Results: A 1-SD increase on the food and service retail scale was associated with a 2.27 (95% confidence interval, 1.42 to 3.61; P < .001) increased odds of being obese. A 1-SD increase in physical disorder was associated with a 2.41 (95% confidence interval, 1.31 to 4.44; P = .005) increased odds of being obese. Other neighborhood scales were not associated with risk for obesity.
Conclusions: Neighborhood food and retail environment and physical disorder around a girl’s home predict risk for obesity across the transition from late childhood to adolescence.
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Body Mass Index: Accounting for Full Time Sedentary Occupation and 24-Hr Self-Reported Time Use
Catrine Tudor-Locke et al.
PLoS ONE, October 2014
Objectives: We used linked existing data from the 2006–2008 American Time Use Survey (ATUS), the Current Population Survey (CPS, a federal survey that provides on-going U.S. vital statistics, including employment rates) and self-reported body mass index (BMI) to answer: How does BMI vary across full time occupations dichotomized as sedentary/non-sedentary, accounting for time spent in sleep, other sedentary behaviors, and light, moderate, and vigorous intensity activities?
Methods: We classified time spent engaged at a primary job (sedentary or non-sedentary), sleep, and other non-work, non-sleep intensity-defined behaviors, specifically, sedentary behavior, light, moderate, and vigorous intensity activities. Age groups were defined by 20–29, 30–39, 40–49, and 50–64 years. BMI groups were defined by 18.5–24.9, 25.0–27.4, 27.5–29.9, 30.0–34.9, and ≥35.0 kg/m2. Logistic and linear regression were used to examine the association between BMI and employment in a sedentary occupation, considering time spent in sleep, other non-work time spent in sedentary behaviors, and light, moderate, and vigorous intensity activities, sex, age race/ethnicity, and household income.
Results: The analysis data set comprised 4,092 non-pregnant, non-underweight individuals 20–64 years of age who also reported working more than 7 hours at their primary jobs on their designated time use reporting day. Logistic and linear regression analyses failed to reveal any associations between BMI and the sedentary/non-sedentary occupation dichotomy considering time spent in sleep, other non-work time spent in sedentary behaviors, and light, moderate, and vigorous intensity activities, sex, age, race/ethnicity, and household income.
Conclusions: We found no evidence of a relationship between self-reported full time sedentary occupation classification and BMI after accounting for sex, age, race/ethnicity, and household income and 24-hours of time use including non-work related physical activity and sedentary behaviors. The various sources of error associated with self-report methods and assignment of generalized activity and occupational intensity categories could compound to obscure any real relationships.
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Janet Tomiyama et al.
Obesity, forthcoming
Objectives: To assess levels of two types of anti-fat bias in obesity specialists, explicit bias, or consciously accessible anti-fat attitudes, and implicit bias, or attitudes that are activated outside of conscious awareness, were examined. This study also assessed changes over time by comparing levels of bias in 2013 to published data from 2001.
Methods: In 232 attendees at the ObesityWeek 2013 conference, we measured explicit anti-fat bias and conducted the Implicit Association Test. These data were compared to those from a study conducted at the 2001 meeting of this group.
Results: Participants exhibited significant implicit and explicit anti-fat/pro-thin bias. Positivity of professional experience with obesity, but not type of professional experience, was correlated with lower explicit anti-fat bias. Compared to 2001, the 2013 sample had lower levels of implicit bias and higher levels of explicit bias.
Conclusions: Although implicit anti-fat attitudes appeared to decrease from 2001 to 2013, explicit anti-fat attitudes increased. Future research should examine whether increasing positive experiences with obese patients reduces anti-fat bias among health professionals. Together, these results suggest that despite the current climate of widespread anti-fat bias, there are pathways toward understanding and ameliorating this bias.
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Sociodemographic Differences and Infant Dietary Patterns
Xiaozhong Wen et al.
Pediatrics, forthcoming
Objectives: To identify dietary patterns in US infants at age 6 and 12 months, sociodemographic differences in these patterns, and their associations with infant growth from age 6 to 12 months.
Methods: We analyzed a subsample (760 boys and 795 girls) of the Infant Feeding Practices Study II (2005–2007). Mothers reported their infants’ intakes of 18 types of foods in the past 7 days, which were used to derive dietary patterns at ages 6 and 12 months by principal component analysis.
Results: Similar dietary patterns were identified at ages 6 and 12 months. At 12 months, infants of mothers who had low education or non-Hispanic African American mothers (vs non-Hispanic white) had a higher score on “High sugar/fat/protein” dietary pattern. Both “High sugar/fat/protein” and “High dairy/regular cereal” patterns at 6 months were associated with a smaller increase in length-for-age z score (adjusted β per 1 unit dietary pattern score, −1.36 [95% confidence interval (CI), −2.35 to −0.37] and −0.30 [−0.54 to −0.06], respectively), while with greater increase in BMI z score (1.00 [0.11 to 1.89] and 0.32 [0.10 to 0.53], respectively) from age 6 to 12 months. The “Formula” pattern was associated with greater increase in BMI z score (0.25 [0.09 to 0.40]). The “Infant guideline solids” pattern (vegetables, fruits, baby cereal, and meat) was not associated with change in length-for-age or BMI z score.
Conclusions: Distinct dietary patterns exist among US infants, vary by maternal race/ethnicity and education, and have differential influences on infant growth. Use of “Infant guideline solids” with prolonged breastfeeding is a promising healthy diet for infants after age 6 months.
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Association of Antibiotics in Infancy With Early Childhood Obesity
Charles Bailey et al.
JAMA Pediatrics, forthcoming
Objective: To assess the impact of antibiotics prescribed in infancy (ages 0-23 months) on obesity in early childhood (ages 24-59 months).
Design, Setting, and Participants: We conducted a cohort study spanning 2001-2013 using electronic health records. Cox proportional hazard models were used to adjust for demographic, practice, and clinical covariates. The study spanned a network of primary care practices affiliated with the Children’s Hospital of Philadelphia including both teaching clinics and private practices in urban Philadelphia, Pennsylvania, and the surrounding region. All children with annual visits at ages 0 to 23 months, as well 1 or more visits at ages 24 to 59 months, were enrolled. The cohort comprised 64 580 children.
Results: Sixty-nine percent of children were exposed to antibiotics before age 24 months, with a mean (SD) of 2.3 (1.5) episodes per child. Cumulative exposure to antibiotics was associated with later obesity (rate ratio [RR], 1.11; 95% CI, 1.02-1.21 for ≥4 episodes); this effect was stronger for broad-spectrum antibiotics (RR, 1.16; 95% CI, 1.06-1.29). Early exposure to broad-spectrum antibiotics was also associated with obesity (RR, 1.11; 95% CI, 1.03-1.19 at 0-5 months of age and RR, 1.09; 95% CI, 1.04-1.14 at 6-11 months of age) but narrow-spectrum drugs were not at any age or frequency. Steroid use, male sex, urban practice, public insurance, Hispanic ethnicity, and diagnosed asthma or wheezing were also predictors of obesity; common infectious diagnoses and antireflux medications were not.
Conclusions and Relevance: Repeated exposure to broad-spectrum antibiotics at ages 0 to 23 months is associated with early childhood obesity. Because common childhood infections were the most frequent diagnoses co-occurring with broad-spectrum antibiotic prescription, narrowing antibiotic selection is potentially a modifiable risk factor for childhood obesity.
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Distance to Store, Food Prices, and Obesity in Urban Food Deserts
Bonnie Ghosh-Dastidar et al.
American Journal of Preventive Medicine, forthcoming
Purpose: To examine the relationship among distance to store, food prices, and obesity.
Methods: The Pittsburgh Hill/Homewood Research on Eating, Shopping, and Health study conducted baseline interviews with 1,372 households between May and December 2011 in two low-income, majority African American neighborhoods without a supermarket. Audits of 16 stores where participants reported doing their major food shopping were conducted. Data were analyzed between February 2012 and February 2013.
Results: Distance to store and prices were positively associated with obesity (p<0.05). When distance to store and food prices were jointly modeled, only prices remained significant (p<0.01), with higher prices predicting a lower likelihood of obesity. Although low- and high-price stores did not differ in availability, they significantly differed in their display and marketing of junk foods relative to healthy foods.
Conclusions: Placing supermarkets in food deserts to improve access may not be as important as simultaneously offering better prices for healthy foods relative to junk foods, actively marketing healthy foods, and enabling consumers to resist the influence of junk food marketing.
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Roberto Treviño et al.
Health Education & Behavior, forthcoming
Introduction: In the United States, one out of every seven low-income children between the ages of 2 and 5 years is at risk for overweight and obesity. Formative research was conducted to determine if preschool children participating in family-style meals consumed the minimum food servings according to U.S. Department of Agriculture dietary guidelines.
Method: Participants were 135 low-income children aged 3 to 4 years who attended an urban child care center. Participant’s parents completed a Family Demographic Questionnaire to provide information on race/ethnicity, parent’s level of education, and household income. Direct observation of children’s food and beverage consumption during school breakfast and lunch was collected over 3 consecutive days. Dietary data were assessed using the Nutrition Data System for Research software. Height and weight measurements were obtained to determine risk for obesity. Descriptive statistics were reported by using the Statistical Package for the Social Sciences Version 16.
Results: Among 135 participants, 98% identified as Mexican American, 75% lived at or below poverty level, and 24% reported a family history of diabetes. Children consumed less than half of the calories provided between breakfast and lunch and did not consume the minimum recommended dietary food servings. Despite the poor dietary intake, physical measurement findings showed 25% obesity prevalence among study participants.
Conclusions: Findings support the need for evidenced-based early childhood obesity prevention programs that provide behavior change opportunities for children, their families, teachers, and menu planners. Family-style meal settings are ideal opportunities for implementing nutrition education strategies to prevent early childhood obesity.
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Offering Variety: A Subtle Manipulation to Promote Healthy Food Choice Throughout the Day
Rachel Burns & Alexander Rothman
Health Psychology, forthcoming
Objective: Providing a variety of food generally increases consumption and enjoyment. This effect is typically associated with unhealthy behavior (e.g., overindulgence at a buffet) and studied during a single meal. Two studies tested whether this effect can be leveraged in a subtle, simple manipulation to promote healthy food choices over the course of a day.
Method: In Studies 1 and 2, 188 and 187 participants, respectively, chose between a sweet and a piece of fruit in the afternoon. The fruit was either the same as or different from fruit that was selected in the morning; choice was not given in the morning. Study 1 tested this effect in the domain of expressed preferences and Study 2 examined actual choice.
Results: In both studies, a second piece of fruit was more likely to be selected in the afternoon if it was different from fruit that was selected in the morning.
Conclusions: These results illustrate how a robust effect that is typically associated with unhealthy outcomes can be harnessed to promote healthy food choices and underscore the importance of conceptualizing eating as a series of interrelated behavioral decisions. This work has implications for applied settings, such as cafeterias, and is distinguished from other simple structural manipulations by its focus on sustaining healthy food choice over the course of the day.
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Behavioral and Neural Valuation of Foods Is Driven by Implicit Knowledge of Caloric Content
Deborah Tang, Lesley Fellows & Alain Dagher
Psychological Science, forthcoming
Abstract:
The factors that affect food choices are critical to understanding obesity. In the present study, healthy participants were shown pictures of foods to determine the impact of caloric content on food choice. Brain activity was then measured while participants bid for a chance to purchase and eat one item. True caloric density, but not individual estimates of calorie content, predicted how much participants were willing to pay for each item. Caloric density also correlated with the neural response to food pictures in the ventromedial prefrontal cortex, a brain area that encodes the value of stimuli and predicts immediate consumption. That same region exhibited functional connectivity with an appetitive brain network, and this connectivity was modulated by willingness to pay. Despite the fact that participants were poor at explicitly judging caloric content, their willingness to pay and brain activity both correlated with actual caloric density. This suggests that the reward value of a familiar food is dependent on implicit knowledge of its caloric content.
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Ann Seibert, Simon Schindler & Marc-André Reinhard
Journal of Applied Social Psychology, forthcoming
Abstract:
Anti-fat bias is marked by a devaluation of overweight people compared with non-overweight persons. Even though belonging to the same group, research on social identity theory (SIT) indicates that overweight people also devaluate overweight others. Merging insights from research on anti-fat bias, SIT, and terror management theory, our study (n = 101) provides new insights on motivational aspects of anti-fat bias by investigating the effects of existential threat on the evaluation of non-overweight and overweight people. Results revealed that participants in the existential threat condition displayed in-group bias: Participants perceiving themselves as non-overweight showed more pronounced anti-fat bias compared with participants in the non-death threat condition. In contrast, participants perceiving themselves as overweight demonstrated less anti-fat bias than controls.
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Simon McCabe et al.
Health Psychology, forthcoming
Objective: To use insights from an integration of the terror management health model and the prototype willingness model to inform and improve nutrition-related behavior using an ecologically valid outcome.
Method: Prior to shopping, grocery shoppers were exposed to a reminder of mortality (or pain) and then visualized a healthy (vs. neutral) prototype. Receipts were collected postshopping and food items purchased were coded using a nutrition database.
Results: Compared with those in the control conditions, participants who received the mortality reminder and who were led to visualize a healthy eater prototype purchased more nutritious foods.
Conclusion: The integration of the terror management health model and the prototype willingness model has the potential for both basic and applied advances and offers a generative ground for future research.
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Generalized Nutrient Taxes Can Increase Consumer Welfare
David Bishai
Health Economics, forthcoming
Abstract:
Certain nutrients can stimulate appetite making them fattening in a way that is not fully conveyed by the calorie content on the label. For rational eaters, this information gap could be corrected by more labeling. As an alternative, this paper proposes a set of positive and negative taxes on the fattening and slimming nutrients in food rather than on the food itself. There are conditions under which this tax plus subsidy system could increase welfare by stopping unwanted weight gain while leaving the final retail price of food unchanged. A nutrient tax system could improve welfare if fattening nutrients, net of their effect on weight, are inferior goods and the fiscal cost of administering the tax is sufficiently low. More data on the price elasticity of demand for nutrients as well as data on how specific nutrients affect satiety and how total calorie intake would be necessary before one could be sure a nutrient tax would work in practice.
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Sara Bleich, Julia Wolfson & Marian Jarlenski
American Journal of Preventive Medicine, forthcoming
Purpose: To describe trends in calories available in large U.S. restaurants.
Methods: Data were obtained from the MenuStat project, a census of menu items in 66 of the 100 largest U.S. restaurant chains, for 2012 and 2013 (N=19,417 items). Generalized linear models were used to calculate (1) the mean change in calories from 2012 to 2013, among items on the menu in both years; and (2) the difference in mean calories, comparing newly introduced items to those on the menu in 2012 only (overall and between core versus non-core items). Data were analyzed in 2014.
Results: Mean calories among items on menus in both 2012 and 2013 did not change. Large restaurant chains in the U.S. have recently had overall declines in calories in newly introduced menu items (–56 calories, 12% decline). These declines were concentrated mainly in new main course items (–67 calories, 10% decline). New beverage (–26 calories, 8% decline) and children’s (–46 calories, 20% decline) items also had fewer mean calories. Among chain restaurants with a specific focus (e.g., burgers), average calories in new menu items not core to the business declined more than calories in core menu items.
Conclusions: Large chain restaurants significantly reduced the number of calories in newly introduced menu items. Supply-side changes to the calories in chain restaurants may have a significant impact on obesity prevention.
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Mark Benden et al.
International Journal of Environmental Research and Public Health, September 2014, Pages 9361-9375
Abstract:
Due to the increasing prevalence of childhood obesity, the association between classroom furniture and energy expenditure as well as physical activity was examined using a standing-desk intervention in three central-Texas elementary schools. Of the 480 students in the 24 classrooms randomly assigned to either a seated or stand-biased desk equipped classroom, 374 agreed to participate in a week-long data collection during the fall and spring semesters. Each participant’s data was collected using Sensewear® armbands and was comprised of measures of energy expenditure (EE) and step count. A hierarchical linear mixed effects model showed that children in seated desk classrooms had significantly lower (EE) and fewer steps during the standardized lecture time than children in stand-biased classrooms after adjusting for grade, race, and gender. The use of a standing desk showed a significant higher mean energy expenditure by 0.16 kcal/min (p < 0.0001) in the fall semester, and a higher EE by 0.08 kcal/min (p = 0.0092) in the spring semester.
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David Just, Brian Wansink & Andrew Hanks
Appetite, December 2014, Pages 242–247
Abstract:
To demonstrate the feasibility of introducing a main dish designed by a professional chef in the National School Lunch Program and to document the impact on child participation, a chef was recruited to design pizza to be served in an upstate New York school district. The pizza was designed to meet both the cost and ingredient requirements of the NSLP. High school students were significantly more likely to select the pizza prepared by the chef. While the chef had no significant impact on main dish consumption given selection, more students took a vegetable and vegetable consumption increased by 16.5%. This pilot study demonstrates the plausibility of using chefs to boost participation in the school lunch program, and potentially increase nutrition through side selection, among high school students.