Food for thought
Is Obesity Un-American? Disease Concerns Bias Implicit Perceptions of National Identity
Erik Lund & Saul Miller
Evolution and Human Behavior, forthcoming
Abstract:
The current research examined whether Americans incorporate obesity into their national identity, and further investigated the role an evolved behavioral immune system plays in shaping Americans’ perceptions of obesity and national identity. Two studies revealed that obesity is not, on the whole, incorporated into the American identity at an implicit level. Moreover, when disease concerns were salient, either because of an experimental priming manipulation (Study 1) or due to recent illness (Study 2), thin individuals (for whom obesity may represent a particularly atypical morphology and thus a heuristic cue to disease) implicitly excluded obesity from the American identity to a greater degree. Thus, implicitly categorizing a subgroup of people as an outgroup pathogen threat may promote behavioral avoidance, exclusion, or stigmatization. This behavioral avoidance, could, in turn lead to less risk of fitness-reducing disease contraction. Further implications for evolutionary theories of disease avoidance, group identity, and discrimination are discussed.
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Racial and Ethnic Differences Associated With Feeding- and Activity-Related Behaviors in Infants
Eliana Perrin et al.
Pediatrics, April 2014, Pages e857-e867
Objective: To examine parental reports of feeding and activity behaviors in a cohort of parents of 2-month-olds and how they differ by race/ethnicity.
Methods: Parents participating in Greenlight, a cluster, randomized trial of obesity prevention at 4 health centers, were queried at enrollment about feeding and activity behaviors thought to increase obesity risk. Unadjusted associations between race/ethnicity and the outcomes of interest were performed by using Pearson χ2 and Kruskal-Wallis tests. Adjusted analyses were performed by using proportional odds logistic regressions.
Results: Eight hundred sixty-three parents (50% Hispanic, 27% black, 18% white; 86% Medicaid) were enrolled. Exclusive formula feeding was more than twice as common (45%) as exclusive breastfeeding (19%); 12% had already introduced solid food; 43% put infants to bed with bottles; 23% propped bottles; 20% always fed when the infant cried; 38% always tried to get children to finish milk; 90% were exposed to television (mean, 346 minutes/day); 50% reported active television watching (mean, 25 minutes/day); and 66% did not meet “tummy time” recommendations. Compared with white parents, black parents were more likely to put children to bed with a bottle (adjusted odds ratio [aOR] = 1.97, P < .004; bottle propping, aOR = 3.1, P < .001), and report more television watching (aOR = 1.6, P = .034). Hispanic parents were more likely than white parents to encourage children to finish feeding (aOR = 1.9, P = .007), bottle propping (aOR = 2.5, P = .009), and report less tummy time (aOR = 0.6, P = .037).
Conclusions: Behaviors thought to relate to later obesity were highly prevalent in this large, diverse sample and varied by race/ethnicity, suggesting the importance of early and culturally-adapted interventions.
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Is Diet Quality Improving? Distributional Changes in the United States, 1989–2008
Timothy Beatty, Biing-Hwan Lin & Travis Smith
American Journal of Agricultural Economics, April 2014, Pages 769-789
Abstract:
This article measures changes in the distribution of dietary quality among adults in the United States over the period 1989–2008. Diet quality is a direct input to health, is often used as a proxy for well-being, and is an outcome variable for a wide variety of economic interventions. For the population as a whole, we find significant improvements across all levels of diet quality. Further, we find improvements for both low-income and higher-income individuals alike. Counterfactual distributions of dietary quality are constructed to investigate the extent to which observed improvements can be attributed to changes in the nutritional content of foods and to changes in population characteristics. We find that 63% of the improvement for all adults can be attributed to changes in food formulation and demographics. Changes in food formulation account for a substantially larger percentage of the dietary improvement within the lower-income population (19.6%) vs. the higher-income population (6.4%).
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Jeffrey Parker & Donald Lehmann
Journal of Consumer Research, forthcoming
Abstract:
To date the effectiveness of inducing lower-calorie choices by providing consumers with calorie information has yielded mixed results. Here four controlled experiments show that adding dish-specific calorie information to menus (calorie posting) tends to result in lower-calorie choices. However, additionally grouping low-calorie dishes into a single “low-calorie” category (calorie organizing) ironically diminishes the positive effects of calorie posting. This outcome appears to be caused by the effect that grouping low-calorie options has on consumers’ consideration sets. When choosing from a calorie-organized menu, consumers are more likely to filter out low-calorie options in the early noncompensatory screening stages of the decision process and, consequently, are less likely to choose low-calorie options. This result disappears when consumers deliberate longer before choosing. These results are important for consumer welfare as well-intentioned restaurateurs (policy makers) may be tempted to institute (mandate) the calorie organization of menus, inadvertently resulting in consumers choosing higher-calorie meals.
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Cigarette smoking and obesity are associated with decreased fat perception in women
Marta Yanina Pepino & Julie Mennella
Obesity, April 2014, Pages 1050–1055
Objective: Smoking and obesity are independently associated with high consumption of high-fat foods in women. We tested whether the co-occurrence of smoking and obesity associates with reduced oral fat perception.
Methods: Four groups of women (14 obese smokers, 11 obese never-smokers, 10 normal-weight smokers, 12 normal-weight never-smokers) rated vanilla puddings that varied in fat content for perceived intensity of creaminess and sweetness, using the general Labeled Magnitude Scale (gLMS), and degree of pleasantness, using the hedonic gLMS. To determine the role of retronasal smell, subjects rated puddings with and without noseclips.
Results: For all groups, perception of creaminess grew with increasing fat concentrations; puddings with any amount of fat were perceived as sweeter than fat-free pudding, and sweetness was enhanced when tasted without noseclips. Overall, obese smokers perceived less creaminess, sweetness, and pleasure while tasting the puddings than did the other three groups (all P values < 0.02).
Conclusion: The ability to perceive fat and sweetness in and derive pleasure from foods is particularly compromised in obese women who smoke, which could contribute to excess calorie intake in this population already at high risk for cardiovascular and metabolic disease. Retronasal olfaction appears not to contribute to blunted flavor perception observed in obese smokers.
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Abigail Saguy, David Frederick & Kjerstin Gruys
Social Science & Medicine, forthcoming
Abstract:
News reporting on research studies may influence attitudes about health risk, support for public health policies, or attitudes towards people labeled as unhealthy or at risk for disease. Across five experiments (N = 2,123) we examined how different news framings of obesity research influence these attitudes. We exposed participants to either a control condition, a news report on a study portraying obesity as a public health crisis, a news report on a study suggesting that obesity may not be as much of a problem as previously thought, or an article discussing weight-based discrimination. Compared to controls, exposure to the public health crisis article did not increase perception of obesity-related health risks but did significantly increase the expression of antifat prejudice in four out of seven comparisons. Across studies, compared to controls, participants who read an article about weight-based discrimination were less likely to agree that overweight constitutes a public health crisis or to support various obesity policies. Effects of exposure to an article questioning the health risks associated with overweight and obesity were mixed. These findings suggest that news reports on the “obesity epidemic” – and, by extension, on public health crises commonly blamed on personal behavior – may unintentionally activate prejudice.
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Food addiction as a causal model of obesity. Effects on stigma, blame, and perceived psychopathology
Janet Latner et al.
Appetite, June 2014, Pages 79–84
Abstract:
The present study examined the impact of the food-addiction model of obesity on weight stigma directed at obese people. Participants (n = 625) were randomly assigned to four experimental conditions. They were asked to read either a food-addiction explanatory model of obesity or a nonaddiction model, and subsequently read a vignette describing a target person who met the characteristics of one of these models and was either obese or of normal weight. Questionnaires assessed participants’ stigmatization and blame of targets and their attribution of psychopathology toward targets. Additional questionnaires assessed stigma and blame directed toward obese people generally, and personal fear of fat. A manipulation check revealed that the food-addiction experimental condition did significantly increase belief in the food-addiction model. Significant main effects for addiction showed that the food-addiction model produced less stigma, less blame, and lower perceived psychopathology attributed to the target described in vignettes, regardless of the target's weight. The food-addiction model also produced less blame toward obese people in general and less fear of fat. The present findings suggest that presenting obesity as an addiction does not increase weight bias and could even be helpful in reducing the widespread prejudice against obese people.
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Olga Yakusheva, Kandice Kapinos & Daniel Eisenberg
Journal of Human Resources, Winter 2014, Pages 234-261
Abstract:
We investigate peer effects in weight gain by exploiting a natural experiment, roommate assignments of 751 male and 845 female first-year college students. Results indicate that females are subject to peer influence in weight gain, with little evidence of peer effects for males. Peer influences appear to be heterogeneous as heavier and thinner females are affected by roommates more than average-weight females, and hierarchical with females influenced only by roommates who are thinner, of a higher socioeconomic status, and more sexually experienced relative to themselves. Similarity of academic performance, religiosity, and political views appears to facilitate transmission of peer influences.
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Employment Impact of Sugar-Sweetened Beverage Taxes
Lisa Powell et al.
American Journal of Public Health, April 2014, Pages 672-677
Objectives: We assessed the impact of sugar-sweetened beverage (SSB) taxes on net employment.
Methods: We used a macroeconomic simulation model to assess the employment impact of a 20% SSB tax accounting for changes in SSB demand, substitution to non-SSBs, income effects, and government expenditures of tax revenues for Illinois and California in 2012.
Results: We found increased employment of 4406 jobs in Illinois and 6654 jobs in California, representing a respective 0.06% and 0.03% change in employment. Declines in employment within the beverage industry occurred but were offset by new employment in nonbeverage industry and government sectors.
Conclusions: SSB taxes do not have a negative impact on state-level employment, and industry claims of regional job losses are overstated and may mislead lawmakers and constituents.
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The Effects of a Soft Drink Tax in the UK
Richard Tiffin, Ariane Kehlbacher & Matthew Salois
Health Economics, forthcoming
Abstract:
The majority of the UK population is either overweight or obese. Health economists, nutritionists and doctors are calling for the UK to follow the example of other European countries and introduce a tax on soft drinks as a result of the perception that high intakes contribute to diet-related disease. We use a demand model estimated with household-level data on beverage purchases in the UK to investigate the effects of a tax on soft drink consumption. The model is a Quadratic Almost Ideal Demand System, and censoring is handled by applying a double hurdle. Separate models are estimated for low, moderate and high consumers to allow for a differential impact on consumption between these groups. Applying different hypothetical tax rates, we conclude that understanding the nature of substitute/complement relationships is crucial in designing an effective policy as these relationships differ between consumers depending on their consumption level. The overall impact of a soft drink tax on calorie consumption is likely to be small.
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Non-Linear Effects of Soda Taxes on Consumption and Weight Outcomes
Jason Fletcher, David Frisvold & Nathan Tefft
Health Economics, forthcoming
Abstract:
The potential health impacts of imposing large taxes on soda to improve population health have been of interest for over a decade. As estimates of the effects of existing soda taxes with low rates suggest little health improvements, recent proposals suggest that large taxes may be effective in reducing weight because of non-linear consumption responses or threshold effects. This paper tests this hypothesis in two ways. First, we estimate non-linear effects of taxes using the range of current rates. Second, we leverage the sudden, relatively large soda tax increase in two states during the early 1990s combined with new synthetic control methods useful for comparative case studies. Our findings suggest virtually no evidence of non-linear or threshold effects.
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Patrik Wennberg et al.
Journal of Epidemiology & Community Health, forthcoming
Background: Accumulating evidence suggests that television (TV) viewing is associated with cardio-metabolic risk, but little is known about how this relationship unfolds over the life course. This study employs a life course epidemiological framework by examining the potential cumulative effect of frequent TV viewing during adolescence and young adulthood on the prevalence of metabolic syndrome in mid-adulthood; and whether TV viewing during adolescence constitutes a sensitive period for the development of the metabolic syndrome in mid-adulthood.
Methods: We used data from the Northern Swedish Cohort, a nationally representative cohort comprising 855 participants (80% of the baseline sample). Data were collected during 1981–2008 and analysed in 2013. Logistic regression was applied to examine the associations between TV viewing at ages 16, 21 and 30 years, and the metabolic syndrome at age 43 years.
Results: Cumulative frequent TV viewing was associated with subsequent prevalence of the metabolic syndrome after adjustment for potential confounders (p for trend=0.026). Watching ‘several shows a day’ compared with ‘one show/week’ or less at age 16 years was associated with the metabolic syndrome at age 43 years after adjustment for later exposure (TV viewing at ages 21 and 30 years) and potential confounders (OR 1.86, 95% CI 1.06 to 3.27).
Conclusions: The number of life periods of frequent TV viewing during adolescence and early adulthood influenced cardio-metabolic risk in mid-adulthood in a dose-dependent manner, corresponding to a cumulative risk life course model. Additionally, TV viewing in adolescence may constitute a sensitive period for the metabolic syndrome in mid-adulthood.
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Obesity, Abdominal Obesity, Physical Activity, and Caloric Intake in U.S. Adults: 1988-2010
Uri Ladabaum et al.
American Journal of Medicine, forthcoming
Background: Obesity and abdominal obesity are independently associated with morbidity and mortality. Physical activity attenuates these risks. We examined trends in obesity, abdominal obesity, physical activity, and caloric intake in U.S. adults from 1988 to 2010.
Methods: Univariate and multivariate analyses were performed using National Health and Nutrition Examination Survey (NHANES) data.
Results: Average body-mass index (BMI) increased by 0.37% (95% CI, 0.30-0.44%) per year in both women and men. Average waist circumference increased by 0.37% (95% CI, 0.30-0.43%) and 0.27% (95% CI, 0.22-0.32%) per year in women and men, respectively. The prevalence of obesity and abdominal obesity increased substantially, as did the prevalence of abdominal obesity among overweight adults. Younger women experienced the greatest increases. The proportion of adults who reported no leisure-time physical activity increased from 19.1% (95% CI, 17.3-21.0%) to 51.7% (95% CI, 48.9-54.5%) in women, and from 11.4% (95% CI, 10.0-12.8%) to 43.5% (95% CI, 40.7-46.3%) in men. Average daily caloric intake did not change significantly. BMI and waist circumference trends were associated with physical activity level, but not caloric intake. The associated changes in adjusted BMIs were 8.3% (95% CI, 6.9-9.6%) higher among women and 1.7% (95% CI, 0.68-2.8%) higher among men with no leisure-time physical activity compared to those with an ideal level of leisure-time physical activity.
Conclusions: Our analyses highlight important dimensions of the public health problem of obesity, including trends in younger women and in abdominal obesity, and lend support to the emphasis placed on physical activity by the Institute of Medicine.
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Robust relation between temporal discounting rates and body mass
David Jarmolowicz et al.
Appetite, July 2014, Pages 63–67
Abstract:
When given the choice between $100 today and $110 in 1 week, certain people are more likely to choose the immediate, yet smaller reward. The present study examined the relations between temporal discounting rate and body mass while accounting for important demographic variables, depressive symptoms, and behavioral inhibition and approach. After having their heights and weights measured, 100 healthy adults completed the Monetary Choice Questionnaire, the Beck Depression Inventory-II, and the Behavioral Inhibition Scale/Behavioral Approach Scale. Overweight and obese participants exhibited higher temporal discounting rates than underweight and healthy weight participants. Temporal discounting rates decreased as the magnitude of the delayed reward increased, even when other variables known to impact temporal discounting rate (i.e., age, education level, and annual household income) were used as covariates. A higher body mass was strongly related to choosing a more immediate monetary reward. Additional research is needed to determine whether consideration-of-future-consequences interventions, or perhaps cognitive control interventions, could be effective in obesity intervention or prevention programs.
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Kyoung Eun Joung et al.
Journal of Clinical Endocrinology & Metabolism, forthcoming
Objectives: The objective of the study was to evaluate the association between early-life adversity and circulating the levels of the adipomyokines such as leptin, adiponectin, and irisin and the inflammatory marker, C-reactive protein (CRP).
Design/Subjects/Setting: This study was a cross-sectional study of 95 adults at a university-based research center. We collected venous blood from participants and analyzed serum for leptin, adiponectin, irisin, and CRP.
Results: Circulating leptin, irisin, and CRP levels were significantly higher in the highest adversity tertile group compared with low and middle tertile groups (P < .001 for leptin, P = .01 for irisin, and P = .02 for CRP). Adiponectin levels were lower in the highest tertile group compared with the low and middle tertile groups (P = .03). After adjusting for demographic variables, physical activity, diet, current mental health, and body mass index, the associations between early-life adversity leptin, irisin, and did not change. However, adiponectin and CRP levels were no longer significantly related to early life adversity.
Conclusion: Early-life adversity is directly associated with elevated circulating leptin and irisin, and indirectly associated with elevated CRP and decreased adiponectin. These findings suggest that these adipomyokines may play a role in the pathogenesis of metabolic abnormality in a population with significant early life adversity.
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A method for neighborhood-level surveillance of food purchasing
David Buckeridge et al.
Annals of the New York Academy of Sciences, forthcoming
Abstract:
Added sugar, particularly in carbonated soft drinks (CSDs), represents a considerable proportion of caloric intake in North America. Interventions to decrease the intake of added sugar have been proposed, but monitoring their effectiveness can be difficult due to the costs and limitations of dietary surveys. We developed, assessed the accuracy of, and took an initial step toward validating an indicator of neighborhood-level purchases of CSDs using automatically captured store scanner data in Montreal, Canada, between 2008 and 2010 and census data describing neighborhood socioeconomic characteristics. Our indicator predicted total monthly neighborhood sales based on historical sales and promotions and characteristics of the stores and neighborhoods. The prediction error for monthly sales in sampled stores was low (2.2%), and we demonstrated a negative association between predicted total sales and median personal income. For each $10,000 decrease in median personal income, we observed a fivefold increase in predicted monthly sales of CSDs. This indicator can be used by public health agencies to implement automated systems for neighborhood-level monitoring of an important upstream determinant of health. Future refinement of this indicator is possible to account for factors such as store catchment areas and to incorporate nutritional information about products.
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Virtually Perfect: Image Retouching and Adolescent Body Image
Kristen Harrison & Veronica Hefner
Media Psychology, forthcoming
Abstract:
Most studies of ideal-body media effects on body image focus on the extreme thinness of the models, not their idealness. In modern media, this idealness is often created or maximized via digital image editing. This experiment tested the effects of image editing outside the research-typical context of exclusive thinness. Original unretouched photographs were manipulated by a professional retoucher to produce unretouched and retouched image conditions. In a third condition (retouched-aware), the retouched images were explicitly labeled as retouched. Adolescents (N = 393, average age 15.43) were randomly assigned to one of these conditions or a no-exposure control, and they completed a questionnaire following exposure. Objectified body consciousness increased and physical self-esteem decreased among male and female adolescents in the retouched-aware condition only. This boomerang effect of retouching awareness is explored in the discussion.
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Counteracting Media's Thin-Body Ideal for Adolescent Girls: Informing Is More Effective Than Warning
Jolanda Veldhuis, Elly Konijn & Jacob Seidell
Media Psychology, forthcoming
Abstract:
The present study investigated whether information or warnings about depictions of the thin-body ideal in mass media are effective in counteracting media-induced negative body perceptions of adolescent girls. Based on counter-advertising and reactance theories, our hypotheses were tested in a 3 (weight labels: information vs. warning vs. no label) × 2 (media models' body shape: thin vs. normal weight) × 2 (self-esteem: lower vs. higher) design (N = 178). Body dissatisfaction, objectified body consciousness, and body comparison with media models served as dependent variables. Pretested media models were systematically combined with various textual weight labels and presented on the front page of a magazine targeted toward girls. The results indicated that a simple information label that provided the weight status of thin media models induced less negative body perceptions in adolescent girls when compared with the use of warning labels or images only. Especially, girls with lower self-esteem then exhibited lower levels of body dissatisfaction and objectified body consciousness. When compared with exposure to images only, the warning labels had little effect on body perceptions by adolescent girls. Thus, informing is more effective than warning in counteracting the undesired effects of the thin-body ideal promoted by the media.
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J. Gan et al.
Appetite, May 2014, Page 214
Abstract:
Associations between sedentary activities and overweight/obesity have been demonstrated in experimental and epidemiological studies; traditionally this has been assumed to involve the displacement of physical activity, promoting positive energy balance and weight gain. Increasingly, researchers are challenging the utility of this ‘energy balance approach’, proposing that sedentary activities may promote weight gain through metabolic perturbations. A three arm, prospective, randomised control trial was conducted in 72 overweight/obese adult males, divided into three equal groups: (i) watching TV; or playing (ii) a non-violent video game; or (iii) a violent video game. The 1-h intervention was followed by a 25-min rest period where a selection of sweet and savoury snacks/drinks was available ad libitum. Data on stress (heart rate, blood pressure, and visual analogue scale (VAS)) were collected throughout. Heart rate, systolic blood pressure, and stress measured by VAS were all significantly higher (p < 0.05) when playing video games (FIFA and COD groups combined) compared to watching TV. Ad libitum energy intake after playing video games was 173 kcal (p < 0.03) higher than controls, in association with a preference for sweet and fatty foods (p < 0.05). Furthermore, playing the violent video game (COD) was individually associated with stronger preference for sweet foods (p < 0.01). A 1-h session of playing video games in overweight/obese adult males is associated with a stress response, and increased calorie intake, which might arise through stress-induced cerebral metabolic perturbations. Furthermore, playing the violent video game may cause an enhanced cerebral metabolic perturbation, associated with preference for sweet foods.
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Timing and Intensity of Light Correlate with Body Weight in Adults
Kathryn Reid et al.
PLoS ONE, April 2014
Abstract:
Light exposure can influence sleep and circadian timing, both of which have been shown to influence weight regulation. The goal of this study was to evaluate the relationship between ambient light, sleep and body mass index. Participants included 54 individuals (26 males, mean age 30.6, SD = 11.7 years). Light levels, sleep midpoint and duration were measured with wrist actigraphy (Actiwatch-L) for 7 days. BMI was derived from self-reported height and weight. Caloric intake was determined from 7 days of food logs. For each participant, light and activity data were output in 2 minute epochs, smoothed using a 5 point (10 minute) moving average and then aggregated over 24 hours. The mean light timing above 500 lux (MLiT500) was defined as the average clock time of all aggregated data points above 500 lux. MLiT500 was positively correlated with BMI (r = 0.51, p<0.001), and midpoint of sleep (r = 0.47, p<0.01). In a multivariable linear regression model including MLiT500 and midpoint of sleep, MLiT500 was a significant predictor of BMI (B = 1.26 SE = 0.34, β = 0.53 p = 0.001, r2Δ = 0.22). Adjusting for covariates, MLiT500 remained an independent predictor of BMI (B = 1.28 SE = 0.36, β = 0.54, p = 0.002, r2Δ = 0.20). The full model accounted for 34.7% of the variance in BMI (p = 0.01). Exposure to moderate levels of light at biologically appropriate times can influence weight, independent of sleep timing and duration.
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Variations in Cereal Volume Affect the Amount Selected and Eaten for Breakfast
Barbara Rolls, Jennifer Meengs & Liane Roe
Journal of the Academy of Nutrition and Dietetics, forthcoming
Abstract:
Food volume could influence both the portions that people take and the amount that they eat, but these effects have had little investigation. The influence of food volume was tested by systematically reducing the flake size of a breakfast cereal so that the cereal was more compact and the same weight filled a smaller volume. In a crossover design, 41 adults ate cereal for breakfast once a week for 4 weeks during 2011 and 2012. The cereal was either standard wheat flakes or the same cereal crushed to reduce the volume to 80%, 60%, or 40% of the standard. A constant weight of cereal was provided in an opaque container and participants poured the amount they wanted into a bowl, added fat-free milk and noncalorie sweetener as desired, and consumed as much as they wanted. Results from a mixed linear model showed that as flake size was reduced, subjects poured a smaller volume of cereal, but still took a greater amount by weight and energy content (both P values <0.0001). Despite these differences, subjects estimated that they had taken a similar number of calories of all versions of the cereal. They ate most of the cereal they took, so as flake size was reduced, breakfast energy intake increased from a mean±standard error of the mean of 286±18 kcal to 358±19 kcal, an increase of a mean±standard error of the mean 34%±7% (P<0.0001). These findings demonstrate that variations in food volume associated with the size of a food's individual pieces affect the portion served, which in turn affects energy intake.
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Stacey Tiberio et al.
JAMA Pediatrics, forthcoming
Objectives: To examine the potential influences of maternal and paternal monitoring of child media exposure and children’s general activities on body mass index (BMI) in middle childhood.
Design, Setting, and Participants: A longitudinal study, taken from a subsample of the Three Generational Study, a predominantly white, Pacific Northwest community sample (overall participation rate, 89.6%), included assessments performed from June 1998 to September 2012. Analyses included 112 mothers, 103 fathers, and their 213 children (55.4% girls) at age 5, 7, and/or 9 years. Participation rates ranged from 66.7% to 72.0% of all eligible Three Generational Study children across the 3 assessments.
Results: Linear mixed-effects modeling indicated that more maternal, but not paternal, monitoring of child media exposure predicted lower child BMI z scores at age 7 years (95% CI, −0.39 to −0.07) and less steeply increasing child BMI z scores from 5 to 9 years (95% CI, −0.11 to −0.01). These effects held when more general parental monitoring, and parent BMI, annual income, and educational level were controlled for. The significant negative effect of maternal media monitoring on children’s BMI z scores at age 7 years was marginally accounted for by the effect of child media time. The maternal media monitoring effect on children’s BMI z score slopes remained significant after adjustment for children’s media time and sports and recreational activity.
Conclusions and Relevance: These findings suggest that parental behaviors related to children’s media consumption may have long-term effects on children’s BMI in middle childhood. They underscore the importance of targeting parental media monitoring in efforts to prevent childhood obesity.
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Oleg Skugarevsky et al.
International Journal of Epidemiology, forthcoming
Background: Observational studies suggest that breastfeeding benefits later maternal child-feeding practices, which in turn may contribute to positive eating attitudes. We investigated the effect of a randomized intervention to increase duration and exclusivity of breastfeeding on pre-adolescent eating attitudes.
Methods: Long-term follow-up of the Promotion of Breastfeeding Intervention Trial (PROBIT), a cluster-randomized trial in 31 maternity hospitals and affiliated polyclinics in Belarus. Sites were randomly assigned an experimental intervention to promote longer duration and exclusivity of breastfeeding in mothers who initiated breastfeeding (n = 16 sites), or a control intervention of continuing usual care (n = 15 sites); 17 046 healthy infants were enrolled in 1996–7, of whom 13 751 (80.7%) completed the Children’s Eating Attitude Test (ChEAT) at 11.5 years of age. A ChEAT score ≥22.5 (85th percentile) was used as an indicator of problematic eating attitudes. Analysis was based on intention-to-treat, accounting for clustering within hospitals/clinics.
Results: Compared with the control arm, the experimental intervention substantially increased breastfeeding exclusivity (43.3% vs 6.4% exclusively breastfed at 3 months of age) and duration of any breastfeeding throughout infancy. The proportion of children with ChEAT scores ≥22.5 was lower in the experimental than control arm (boys 11.4% vs 17.2%; girls 18.5% vs 23.4%) [cluster-adjusted odds ratio (OR), boys: 0.44; 95% confidence interval (CI): 0.21,0.93; girls: 0.51; 95% CI: 0.27,0.99). Results were robust to adjustment for potential confounders and using a ChEAT score ≥25.5 (91st percentile) as the outcome (OR: 0.53; 95% CI: 0.28,1.03).
Conclusions: An intervention to improve the duration and exclusivity of breastfeeding among term infants in Belarus was associated with a reduction in problematic eating attitudes at 11.5 years of age.
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Attentional retraining can reduce chocolate consumption
Eva Kemps et al.
Journal of Experimental Psychology: Applied, March 2014, Pages 94-102
Abstract:
There is emerging evidence that attentional biases are related to the consumption of substances such as alcohol and tobacco, and that attentional bias modification can reduce unwanted consumption of these substances. We present evidence for the first time to our knowledge that the same logical argument applies in the food and eating domain. We conducted two experiments that used a modified dot probe paradigm to train undergraduate women to direct their attention toward (“attend”) or away from (“avoid”) food cues (i.e., pictures of chocolate). In Experiment 1, attentional bias for chocolate cues increased in the “attend” group, and decreased in the “avoid” group. Experiment 2 showed that these training effects generalized to novel, previously unseen chocolate pictures. Importantly, attentional retraining affected chocolate consumption and craving. In both experiments, participants in the “avoid” group ate less chocolate in a so-called taste test than did those in the “attend” group. In addition, in Experiment 2, but not in Experiment 1, the “attend” group reported stronger chocolate cravings following training, whereas the “avoid” group reported less intense cravings. The results support predictions of cognitive–motivational models of craving and consumption that attentional biases play a causal role in consumption behavior. Furthermore, they present a promising avenue for tackling unwanted food cravings and (over)eating.
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Genetic influences on dietary variety. Results from a twin study
Benjamin Scheibehenne et al.
Appetite, June 2014, Pages 133–140
Abstract:
The heritability of variety seeking in the food domain was estimated from a large sample (N = 5543) of middle age to elderly monozygotic and dizygotic twins from the “Virginia 30,000” twin study. Different dietary variety scores were calculated based on a semi-quantitative food choice questionnaire that assessed consumption frequencies and quantities for a list of 99 common foods. Results indicate that up to 30% of the observed variance in dietary variety was explained through heritable influences. Most of the differences between twins were due to environmental influences that are not shared between twins. Additional non-genetic analyses further revealed a weak relationship between dietary variety and particular demographic variables, including socioeconomic status, age, sex, religious faith, and the number of people living in the same household.
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The Effect of Holiday Weight Gain on Body Weight
Dale Schoeller
Physiology & Behavior, forthcoming
Abstract:
The topic of holiday weight gain has been a frequent subject of the lay media, however, scientific interest has only been recent. Multiple studies in Western societies have reported average weight gains among adults during the period between mid-November and mid-January that were about 0.5 kg. The range in individual weight changes was large, however, and the already overweight and obese gain more weight than those who are healthy weight. When the average gain across the year was also measured, the holiday weight was the major contributor to annual excess weight gain. Efforts patterned to increase awareness to energy balance and body weight have been shown to be successful at reducing such gain. An exception to holiday weight gain being a major contributor to annual excess gain has been children, in whom summer weight gains have been observed to be the major contributor to average excess weight gain.
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The Association Between Food Prices and the Blood Glucose Level of US Adults With Type 2 Diabetes
Tobenna Anekwe & Ilya Rahkovsky
American Journal of Public Health, April 2014, Pages 678-685
Objectives: We estimated the association between the price of healthy and less-healthy food groups and blood sugar among US adults with type 2 diabetes.
Methods: We linked 1999–2006 National Health and Nutrition Examination Survey health information to food prices contained in the Quarterly Food-at-Home Price Database. We regressed blood sugar levels on food prices from the previous calendar quarter, controlling for market region and a range of other covariates. We also examined whether the association between food prices and blood sugar varies among different income groups.
Results: The prices of produce and low-fat dairy foods were associated with blood sugar levels of people with type 2 diabetes. Specifically, higher prices for produce and low-fat dairy foods were associated with higher levels of glycated hemoglobin and fasting plasma glucose 3 months later. Food prices had a greater association with blood sugar for low-income people than for higher-income people, and in the expected direction.
Conclusions: Higher prices of healthy foods were associated with increased blood sugar among people with type 2 diabetes. The association was especially pronounced among low-income people with type 2 diabetes.