Relationship between dietary restraint, energy intake, physical activity, and body weight: A prospective analysis

shinyOPTIK, a User-Friendly R Shiny Application for Visualizing Cancer Risk Factors and Mortality Across the University of Kansas Cancer Center Catchment Area

PURPOSE

The University of Kansas Cancer Center (KU Cancer Center) recently developed a data warehouse to Organize and Prioritize Trends to Inform KU Cancer Center (OPTIK). The OPTIK database aggregates and standardizes data collected across the bistate catchment area served by the KU Cancer Center. To improve the usability of the OPTIK database, we developed shinyOPTIK, a user-friendly, interactive web application for visualizing cancer risk factor and mortality rate data across the KU Cancer Center Catchment area.

METHODS

Data in the OPTIK database were first consolidated at the county level across the KU Cancer Center catchment area. Next, the shinyOPTIK development team met with the KU Cancer Center leadership to discuss the needs and priorities of the shinyOPTIK web application. shinyOPTIK was developed under the R Shiny framework and consists of a user interface (ui.R) and a web server (server.R). At present, shinyOPTIK can be used to generate county-level geographical heatmaps; bar plots of demographic, screening, and risk factors; and line plots to visualize temporal trends at different Rural-Urban Continuum Codes (RUCCs), rural-urban status, metropolitan, or county levels across the KU Cancer Center catchment area.

RESULTS

Two examples, adult obesity prevalence and lung cancer mortality, are presented to illustrate how researchers can use shinyOPTIK. Each example is accompanied by post hoc visualizations to help explain key observations in terms of rural-urban disparities.

CONCLUSION

Although shinyOPTIK was developed to improve understanding of spatial and temporal trends across the population served by the KU Cancer Center, our hope is that the description of the steps involved in the creation of this tool along with open-source code for our application provided herein will serve as a guide for other research centers in the development of similar tools.

Nutritional Status and its Associations with Eating Behavior and Diet Quality among Adult: A Cross-Sectional Study

BACKGROUND: Obesity among adults is a significant public health problem. Diet quality might be influenced by eating behavior and is associated with nutritional status, but research is lacking in obese adults in Indonesia. AIM: The purpose of this study was to investigate the relationship between eating behavior, diet quality, and obesity. METHODS: A cross-sectional study was carried out among 144 respondents (39.6% males and 60.4% females), aged 39.07 ± 5.48 years, who were selected using stratified random sampling from five subdistrict in Malang City, East Java, Indonesia. The eating behavior score was calculated using the Dutch Eating Behavior Questionnaire (DEBQ) and the diet quality using the Diet Quality Index International (DQI-I) from SQ-FFQ. Association of eating behavior, diet quality, and nutritional status was analyzed using logistic regression analysis. RESULTS: The study showed that the prevalence of obesity among female adults was higher (31.9%) than males (18.8%). The female participant had a two-fold higher likelihood of being overweight or obese than the male participant (OR = 2.25, 95% CI: 1.077; 4.071, p < 0.05). The average diet quality score was 57.99 ± 7.26 or 80% from a total score of 100. There was no significant difference in total DQI-I and component scores, including variety, adequacy, moderation, and overall balance across nutritional status and sex, p > 0.005. The poor-diet quality was higher in the overweight and obesity group (43.75 %) than the normal group (16.67%). There was a statistically significant difference of restrained eating with overweight and obesity status (p < 0.05) with OR 2,652 (CI 95% 1.149; 6.119) and female (OR 2.496, CI 95% 1.195; 5.212, p < 0.05). CONCLUSIONS: It can be concluded that obesity was prevalent in female adults, and there is a relationship between obesity and restraint eating among adults. Future studies should examine the causal effects of eating behaviors on quality diet and in the development of obesity.

Polish Adaptation of the Dutch Eating Behaviour Questionnaire (DEBQ): The Role of Eating Style in Explaining Food Intake-A Cross-Sectional Study

Knowledge of associations between emotional, external, and restrained eating with food choices is still limited due to the inconsistent results of the previous research. The aim of the study was to adopt the Dutch Eating Behavior Questionnaire (DEBQ) and then to examine the relationship between emotional, external, and restrained eating styles and dietary patterns distinguished on the basis of intake of fruit and vegetables (fresh and processed separately), fruit and/or vegetable unsweetened juices, sweets and salty snacks, and the adequacy of fruit and vegetable intake. The cross-sectional study was conducted in 2020, in a sample of 1000 Polish adults. The questionnaire consisted of the Dutch Eating Behavior Questionnaire, questions on selected food groups intake, and metrics. DEBQ structure was tested using both exploratory and confirmatory factor analysis (EFA, CFA) and structural equation modelling (SEM), while multi-group analysis was used to test measurement invariance. Logistic regression was applied to investigate the association between eating styles and dietary patterns, identified with the use of K-means cluster analysis. EFA, CFA and SEM revealed a three-factor, 29-item tool with satisfactory psychometric parameters. Restrained eating (ResEat) and external eating (ExtEat) were found to decrease chances of low intake of both favorable (fruit, vegetables, and unsweetened juices) and unfavorable (sweets and salty snacks) foods and increased the chances of their moderate intake. ResEat increased the probability of the high intake of favorable and moderate or high intake of unfavorable foods. ResEat and ExtEat were predisposed to adequate intake of fruit and vegetables while emotional eating had the opposite effect. Gender, education, and BMI were also found to determine food intake. Our results provide evidence that both eating styles and sociodemographic characteristics should be taken into account while explaining food intake as they may favor healthy and unhealthy eating in different ways.

Resting state differences between successful and unsuccessful restrained eaters

Restrained eating is a popular weight loss strategy for young women that tends to have limited effectiveness over extended periods of time. Although previous studies have explored and identified possible personality and behavior differences between successful and unsuccessful restrained eaters (REs), there has been a paucity of research on neurophysiological differences.Towards addressing this gap, we assessed brain resting state (Rs) differences in groups of unsuccessful REs (N = 39) and successful REs (N = 31). In line with hypotheses, unsuccessful REs displayed reduced regional homogeneity in brain regions involved in cognitive control (inferior parietal lobe) compared to successful REs. Regions involved in conflict monitoring (anterior cingulate cortex) were also observed to be comparatively less active in the unsuccessful RE group. Finally, based on analyses of independent components and seed-based functional connectivity, regions involved in conflict monitoring and cognitive control, especially those localized within the frontoparietal network, showed weaker connectivities among unsuccessful REs compared to their successful counterparts.These results underscore specific brain Rs differences between successful REs and unsuccessful REs in regions implicated in cognitive control and conflict monitoring.

ImpulsePal: The systematic development of a smartphone app to manage food temptations using intervention mapping

BACKGROUND

Impulsive processes driving eating behaviour can often undermine peoples' attempts to change their behaviour, lose weight and maintain weight loss.

AIM

To develop an impulse management intervention to support weight loss in adults.

METHODS

Intervention Mapping (IM) was used to systematically develop the "ImpulsePal" intervention. The development involved: (1) a needs assessment including a qualitative study, Patient and Public advisory group and expert group consultations, and a systematic review of impulse management techniques; (2) specification of performance objectives, determinants, and change objectives; (3) selection of intervention strategies (mapping of change techniques to the determinants of change); (4) creation of programme materials; (5) specification of adoption and implementation plans; (6) devising an evaluation plan.

RESULTS

Application of the IM Protocol resulted in a smartphone app that could support reductions in unhealthy (energy dense) food consumption, overeating, and alcoholic and sugary drink consumption. ImpulsePal includes inhibition training, mindfulness techniques, implementation intentions (if-then planning), visuospatial loading, use of physical activity for craving management, and context-specific reminders. An "Emergency Button" was also included to provide access to in-the-moment support when temptation is strong.

CONCLUSIONS

ImpulsePal is a novel, theory- and evidence-informed, person-centred app that aims to support impulse management for healthier eating. Intervention Mapping facilitated the incorporation of app components that are practical operationalisations of change techniques targeting our specific change objectives and their associated theoretical determinants. Using IM enabled transparency and provided a clear framework for evaluation, and enhances replicability and the potential of the intervention to accomplish the desired outcome of facilitating weight loss through dietary change.

When impulsive behaviours do not equal self-control failures: the (added) value of temptation enactments

Most work on self-control and impulsivity typically assumes, more or less tacitly, that people value self-control as more important than succumbing to temptations. According to this narrative, people regard impulsive behaviours as ‘failures’ of self-control and experience negative self-evaluations such as feelings of guilt or shame in response. Here, we direct attention to a neglected but crucial meta-behavioural valuation dimension of impulsive behaviour. We posit that individual differences in people's valuation of temptation enactment (VOTE) qualify whether and to what extent impulsive behaviours trigger negative self-evaluations and whether and to what extent people feel motivated to self-improve. Using a newly constructed VOTE scale, we first show that individual differences in VOTE can be reliably measured and clearly distinguished from traditional impulsivity or self-control scales (Studies 1–3; total N = 576). Across three subsequent studies (total N = 460), we then demonstrate that high VOTE, as compared with low VOTE, reduces the link between impulsive behaviours and negative self-conscious emotions (Studies 4 and 5), as well as between past impulsive behaviour and self-improvement motivation (Study 6). These findings have implications for the discourse on self-control failure and for the link between impulsive behaviour and self-evaluation, self-improvement motivation, and well-being.

Dietary intake on days with and without hypoglycemia in youth with type 1 diabetes: The Flexible Lifestyle Empowering Change trial

OBJECTIVE

To address a common perception that hypoglycemia is associated with increased dietary intake, we examined calorie and carbohydrate consumption on days with and without hypoglycemia among adolescents with type 1 diabetes (T1D).

METHODS

Days (N = 274) with 24-hour dietary recalls and continuous glucose monitoring were available for 122 adolescents with T1D in the Flexible Lifestyle Empowering Change trial (age 13-16 years, diabetes duration >1 year, hemoglobin A1c 8%-13%). Days with no hypoglycemia, clinical hypoglycemia (54-69 mg/dL) or clinically serious hypoglycemia (<54 mg/dL) were further split into night (12-5:59 am) and day (6 am-11:59 pm). Mixed models tested whether intake of calories or carbohydrates was greater on days with than without hypoglycemia.

RESULTS

Fifty-nine percent, 23% and 18% of days had no hypoglycemia, clinical hypoglycemia and clinically serious hypoglycemia, respectively. Intake of calories and carbohydrates was not statistically significantly different on days with clinical hypoglycemia (57.2 kcal [95% CI -126.7, 241.5]; 12.6 g carbohydrate [95% CI -12.7, 38.0]) or clinically serious hypoglycemia (-74.0 kcal [95% CI -285.9, 137.9]; (-7.8 g carbohydrate [95% CI -36.8, 21.1]), compared to days without hypoglycemia. Differences by day and night were not statistically significant.

CONCLUSIONS

Among adolescents with T1D, daily intake of calories and carbohydrates did not differ on days with and without hypoglycemia. It is possible that hypoglycemic episodes caused by undereating relative to insulin dosing, followed by overeating, leading to a net neutral difference. Given the post-hoc nature of these analyses, larger studies should be designed to prospectively test the hypoglycemia-diet relationship.

A review of the relationship between eating behavior, obesity and functional brain network organization

Obesity is a major public health issue affecting nearly 40% of American adults and is associated with increased mortality and elevated risk for a number of physical and psychological illnesses. Obesity is associated with impairments in executive functions such as decision making and inhibitory control, as well as in reward valuation, which is thought to contribute to difficulty sustaining healthy lifestyle behaviors, including adhering to a healthy diet. Growing evidence indicates that these impairments are accompanied by disruptions in functional brain networks, particularly those that support self-regulation, reward valuation, self-directed thinking and homeostatic control. Weight-related differences in task-evoked and resting-state connectivity have most frequently been noted in the executive control network (ECN), salience network (SN) and default mode network (DMN), with obesity generally being associated with weakened connectivity in the ECN and enhanced connectivity in the SN and DMN. Similar disruptions have been observed in the much smaller literature examining the relationship between diet and disordered eating behaviors on functional network organization. The purpose of this narrative review was to summarize what is currently known about how obesity and eating behavior relate to functional brain networks, describe common patterns and provide recommendations for future research based on the identified gaps in knowledge.

One size does not fit all: Trajectories of body image development and their predictors in early adolescence

Background: Negative body image predicts many adverse outcomes. The current study prospectively examined patterns of body esteem development in early adolescence and identified predictors of developmental subtypes. Methods: 328 girls and 429 boys reported annually across a 4-year period (Mage at baseline = 11.14, SD = 0.35) on body esteem, appearance ideal internalization, perceived sociocultural pressures, appearance comparisons, appearance-related teasing, self-esteem, positive and negative affect, and dietary restraint. We performed latent class growth analyses to identify the most common trajectories of body esteem development and examine risk and protective factors for body image development. Results: Three developmental subgroups were identified: (a) high body esteem (39.1%); (b) moderate body esteem (46.1%); and (c) low body esteem (14.8%). Body esteem was stable within the low trajectory and there were minor fluctuations in the high and moderate trajectories. Greater appearance-related teasing, lower self-esteem, less positive affect, and higher dietary restraint predicted the low trajectory, whereas higher self-esteem and lower dietary restraint best predicted the high trajectory. Conclusions: Low body esteem appears to be largely stable from age 11 years. Prevention programming may be enhanced by incorporating components to address transdiagnostic resilience factors such as self-esteem and positive affect.

Comparing eating behaviours, and symptoms of depression and anxiety between Spain and Greece during the COVID-19 outbreak: Cross-sectional analysis of two different confinement strategies

OBJECTIVE

We compared eating behaviours, and depressive and anxiety symptoms in two countries with different confinement strictness strategies and different levels of COVID-19 pandemic.

METHOD

A web-based cross-sectional survey was administered during and shortly after the COVID-19 related lockdown in Spain and Greece. Multivariable linear regression analyses were performed to identify country differences associated with eating behaviour, and symptoms of depression and anxiety.

RESULTS

This study included 1,002 responders in Spain and 839 in Greece. The mean ± SD of restraint, emotional and external eating was 2.5 ± 0.79, 2.1 ± 0.81 and 2.6 ± 0.65 in Spain, whereas 2.7 ± 0.85, 2.3 ± 0.99 and 2.9 ± 0.74 in Greece. Spanish participants had lower average scores of restraint and external eating compared to Greek participants (p < .001), but no difference was seen for emotional eating. In Spain, 13.6%, and 12.3% of the survey respondents reported moderate to severe depressive and anxiety symptoms, respectively, whereas in Greece the respective values were 18.8 and 13.2%. After adjusting for several risk factors, a higher prevalence of anxiety symptoms was observed in Spain compared to Greece (p = .001), but no difference was seen for depressive symptoms.

CONCLUSIONS

This study demonstrated high scores of inappropriate eating behaviours and a high frequency of depressive and anxiety symptoms in two Mediterranean countries during the COVID-19 outbreak. Our findings revealed that compared to Greek participants, Spanish participants, that faced more severe COVID-19 pandemic and stricter lockdown measures, were associated with lower restraint and external eating and increased anxiety symptoms, but not with depressive symptoms or emotional eating.

Does Eating Addiction Favor a More Varied Diet or Contribute to Obesity?-The Case of Polish Adults

The rapidly increasing prevalence of overweight and obesity indicates a need to search for their main causes. Addictive-like eating and associated eating patterns might result in overconsumption, leading to weight gain. The aim of the study was to identify the main determinants of food intake variety (FIV) within eating addiction (EA), other lifestyle components, and sociodemographic characteristics. The data for the study were collected from a sample of 898 Polish adults through a cross-sectional survey in 2019. The questionnaire used in the study included Food Intake Variety Questionnaire (FIVeQ), Eating Preoccupation Scale (EPS), and questions regarding lifestyle and sociodemographic factors. High eating addiction was found in more than half of the people with obesity (54.2%). In the study sample, physical activity at leisure time explained FIV in the greatest manner, followed by the EPS factor: eating to provide pleasure and mood improvement. In the group of people with obesity, the score for this EPS factor was the best predictor of FIV, in that a higher score was conducive to a greater variety of food intake. Sociodemographic characteristics differentiated FIV only within groups with normal body weight (age) and with overweight (education). In conclusion, food intake variety (FIV) was associated with physical activity at leisure time, and then with EPS factor “Eating to provide pleasure and mood improvement”, whereas sociodemographic characteristics were predictors of FIV only within groups identified by body mass index (BMI). Nevertheless, our observations regarding the eating to provide pleasure and mood improvement factor and its associations with food intake variety indicate a need for further research in this area. Future studies should also use other tools to explicitly explain this correlation.

Psychological distress in patients with obstructive sleep apnoea: The role of hostility and coping self-efficacy

We aimed to assess whether hostility and coping self-efficacy are associated with psychological distress in obstructive sleep apnoea patients. Furthermore, we examined whether coping self-efficacy mediates the association between hostility and psychological distress. We included 150 obstructive sleep apnoea patients (Apnoea-Hypopnoea Index ⩾5; 68% male; mean age: 48.9 ± 9.5 years). Regression models showed that hostility and poor coping self-efficacy were strongly associated with psychological distress in obstructive sleep apnoea patients. All assessed coping self-efficacy dimensions mediated the association between hostility and psychological distress. Coping self-efficacy for stopping unpleasant emotions and thoughts showed the strongest association with a lower level of psychological distress.

Daily self-weighing and weight gain prevention: a longitudinal study of college-aged women

Daily self-weighing has been suggested as an important factor for weight loss maintenance among samples with obesity. This study is a secondary analysis that examined daily self-weighing in association with weight and body composition outcomes over 2 years among young women with vulnerability for weight gain. Women (N = 294) of varying weight status completed self-weighing frequency questionnaires and weight was measured in the clinic at baseline, 6 months, 1, and 2 years; DXA scans were completed at baseline, 6 months and 2 years. Multilevel models examined the relationship between daily self-weighing (at any point in the study) and trajectories of BMI and body fat percentage. Daily self-weighing was associated with significant declines in BMI and body fat percent over time. Future research is needed to examine causal relations between daily self-weighing and weight gain prevention. Nonetheless, these data extend the possibility that daily self-weighing may be important for prevention of unwanted weight gain.

Effect of the CRF1-receptor antagonist pexacerfont on stress-induced eating and food craving

RATIONALE

In rodents, antagonism of receptors for corticotropin-releasing factor (CRF) blocks stress-induced reinstatement of drug or palatable food seeking.

OBJECTIVE

To test anticraving properties of the CRF₁ antagonist pexacerfont in humans.

METHODS

We studied stress-induced eating in people scoring high on dietary restraint (food preoccupation and chronic unsuccessful dieting) with body-mass index (BMI) >22. In a double-blind, between-groups trial, 31 "restrained" eaters were stabilized on either pexacerfont (300 mg/day for 7 days, then 100 mg/day for 21 days) or placebo. On day 15, they underwent a math-test stressor; during three subsequent visits, they heard personalized craving-induction scripts. In each session, stress-induced food consumption and craving were assessed in a bogus taste test and on visual analog scales. We used digital video to monitor daily ingestion of study capsules and nightly rating of food problems/preoccupation on the Yale Food Addiction Scale (YFAS).

RESULTS

The study was stopped early due to an administrative interpretation of US federal law, unrelated to safety or outcome. The bogus taste tests suggested some protective effect of pexacerfont against eating after a laboratory stressor (r _effect = 0.30, 95 % CL = -0.12, 0.63, Bayes factor 11.30). Similarly, nightly YFAS ratings were lower with pexacerfont than placebo (r _effect = 0.39, CI 0.03, 0.66), but this effect should be interpreted with caution because it was present from the first night of pill ingestion, despite pexacerfont's slow pharmacokinetics.

CONCLUSIONS

The findings may support further investigation of the anticraving properties of CRF₁ antagonists, especially for food.

Impulse control and restrained eating among young women: Evidence for compensatory cortical activation during a chocolate-specific delayed discounting task

Theory and associated research indicate that people with elevated restrained eating (RE) scores have higher risk for binge eating, future bulimic symptom onset and weight gain. Previous imaging studies have suggested hyper-responsive reward brain area activation in response to food cues contributes to this risk but little is known about associated neural impulse control mechanisms, especially when considering links between depleted cognitive resources related to unsuccessful RE. Towards illuminating this issue, we used a chocolate-specific delayed discounting (DD) task to investigate relations between RE scores, behavior impulsivity, and corresponding neural impulse control correlates in a functional magnetic resonance imaging (fMRI) study of 27 young women. Specifically, participants were required to choose between more immediate, smaller versus delayed, larger hypothetical chocolate rewards following initial consumption of a chocolate. As predicted, RE scores were correlated positively with behavior impulse control levels. More critically, higher RE scores were associated with stronger activation in impulse control region, the dorsal-lateral prefrontal cortex (DLPFC) during the completion of difficult decision trials reflecting higher cognitive demands and resource depletion relative to easy decision trials. Exploratory analyses revealed a positive correlation between RE scores and activity in a reward system hub, the right striatum. Moreover, a positive correlation between left DLPFC and striatum activation was posited to reflect, in part, impulse control region compensation in response to stronger reward signal among women with RE elevations. Findings suggested impulse control lapses may contribute to difficulties in maintaining RE, particularly when cognitive demands are high.

Spontaneous regional brain activity links restrained eating to later weight gain among young women

Theory and prospective studies have linked restrained eating (RE) to risk for future weight gain and the onset of obesity, but little is known about resting state neural activity that may underlie this association. To address this gap, resting fMRI was used to test the extent to which spontaneous neural activity in regions associated with inhibitory control and food reward account for potential relations between baseline RE levels and changes in body weight among dieters over a one-year interval. Spontaneous regional activity patterns corresponding to RE were assessed among 50 young women using regional homogeneity (ReHo) analysis, which measured temporal synchronization of spontaneous fluctuations within a food deprivation condition. Analyses indicated higher baseline RE scores predicted more weight gain at a one-year follow-up. Furthermore, food-deprived dieting women with high dietary restraint scores exhibited more spontaneous local activity in brain regions associated with the expectation and valuation for food reward [i.e., orbitofrontal cortex (OFC)/ventromedial prefrontal cortex (VMPFC)] and reduced spontaneous local activity in inhibitory control regions [i.e., bilateral dorsal-lateral prefrontal cortex (DLPFC)] at baseline. Notably, the association between baseline RE and follow-up weight gain was mediated by decreased local synchronization of the right DLPFC in particular and, to a lesser degree, increased local synchronization of the right VMPFC. In conjunction with previous research, these findings highlight possible neural mechanisms underlying the relation between RE and risk for weight gain.

The relative contributions of body image evaluation and investment in the prediction of dietary restraint in men

This study examined the importance of body image evaluation and investment to predict dietary restraint in men ( N = 272). Measures of physical activity, evaluation, investment and dietary restraint were completed. A hierarchical regression was conducted to predict dietary restraint from physical activity and body mass index (entered on the first step), body image evaluation (entered on the second step) and investment (entered on the final step). The overall regression was significant, F(4, 271) = 15.12, p < .001, R2adj = .17). Body mass index, physical activity and body image investment were significant positive predictors of dietary restraint. The present findings emphasize measuring body image investment.

Development and aetiology of body dissatisfaction in adolescent boys and girls

This longitudinal study aims to describe the development of body dissatisfaction (BD), measured with the Contour Drawing Rating Scale, between the ages of 14 and 18, and to identify factors associated with BD at age 18, among 413 adolescents. Between the ages of 14 and 18, the proportion of girls wanting to be thinner increased, although it remained unchanged among boys. A ratio of 1:2 girls and 1:5 boys reported having seriously tried to lose weight. Factors associated with BD in girls at age 18 were (1) wanting to be thinner, (2) body mass index (BMI), (3) weight control behaviours and (4) negative comments about weight. Factors associated with BD in boys at age 18 were (1) wanting to be thinner or bigger, (2) BMI, (3) having experienced sexual intercourse and (4) negative comments about weight. The high prevalence of BD and weight-related concerns suggest a need for early interventions.

Worry or craving? A selective review of evidence for food-related attention biases in obese individuals, eating-disorder patients, restrained eaters and healthy samples

Living in an ‘obesogenic’ environment poses a serious challenge for weight maintenance. However, many people are able to maintain a healthy weight indicating that not everybody is equally susceptible to the temptations of this food environment. The way in which someone perceives and reacts to food cues, that is, cognitive processes, could underlie differences in susceptibility. An attention bias for food could be such a cognitive factor that contributes to overeating. However, an attention bias for food has also been implicated with restrained eating and eating-disorder symptomatology. The primary aim of the present review was to determine whether an attention bias for food is specifically related to obesity while also reviewing evidence for attention biases in eating-disorder patients, restrained eaters and healthy-weight individuals. Another aim was to systematically examine how selective attention for food relates (causally) to eating behaviour. Current empirical evidence on attention bias for food within obese samples, eating-disorder patients, and, even though to a lesser extent, in restrained eaters is contradictory. However, present experimental studies provide relatively consistent evidence that an attention bias for food contributes to subsequent food intake. This review highlights the need to distinguish not only between different (temporal) attention bias components, but also to take different motivations (craving v. worry) and their impact on attentional processing into account. Overall, the current state of research suggests that biased attention could be one important cognitive mechanism by which the food environment tempts us into overeating.

Elevated objectively measured but not self-reported energy intake predicts future weight gain in adolescents

BACKGROUND

Although obesity putatively occurs when individuals consume more calories than needed for metabolic needs, numerous risk factor studies have not observed significant positive relations between reported caloric intake and future weight gain, potentially because reported caloric intake is inaccurate.

OBJECTIVE

The present study tested the hypothesis that objectively measured habitual energy intake, estimated with doubly labeled water, would show a stronger positive relation to future weight gain than self-reported caloric intake based on a widely used food frequency measure.

DESIGN

Two hundred and fifty-three adolescents completed a doubly labeled water (DLW) assessment of energy intake (EI), a food frequency measure, and a resting metabolic rate (RMR) assessment at baseline, and had their body mass index (BMI) measured at baseline and at 1- and 2-year follow-ups.

RESULTS

Controlling for baseline RMR, elevated objectively measured EI, but not self-reported habitual caloric intake, predicted increases in BMI over a 2-year follow-up. On average, participants under-reported caloric intake by 35%.

CONCLUSIONS

RESULTS provide support for the thesis that self-reported caloric intake has not predicted future weight gain because it is less accurate than objectively measured habitual caloric intake, suggesting that food frequency measures can lead to misleading findings. However, even objectively measured caloric intake showed only a moderate relation to future weight gain, implying that habitual caloric intake fluctuates over time and that it may be necessary to conduct serial assessments of habitual intake to better reflect the time-varying effects of caloric intake on weight gain.

Effortless inhibition: habit mediates the relation between self-control and unhealthy snack consumption

In contrast to prevailing beliefs, recent research suggests that trait self-control promotes health behavior not because those high in self-control are more successful at resisting single temptations, but rather because they develop adaptive habits. The present paper presents a first empirical test of this novel suggestion by investigating the mediating role of habit in explaining the relation between self-control and unhealthy snacking behavior. Results showed that self-control was negatively associated with unhealthy snack consumption and unhealthy snacking habits. As hypothesized, the relation between self-control and unhealthy snack intake was mediated by habit strength. Self-control was not associated with fruit consumption or fruit consumption habits. These results provide the first evidence for the notion that high self-control may influence the formation of habits and in turn affect behavior. Moreover, results imply that self-control may be particularly influential in case of inhibiting unhealthy food intake rather than promoting healthy food intake.

A twin study of differences in the response of plasma ghrelin to a milkshake preload in restrained eaters

BACKGROUND

Genetic, physiological, and psychological factors can affect food intake, but twin studies can distinguish inherited from environmental contributors. We examined the influence of attempted cognitive control of eating ("restrained eating") on levels of appetite-regulating hormones.

METHODS

Sixteen female, monozygotic twin pairs, discordant for Restraint Scale score (i.e., one twin a restrained eater with score>15 whereas the co-twin was unrestrained), were selected from the University of Washington Twin Registry. Serial plasma ghrelin concentrations were monitored during meals and a preload study paradigm involving intake of a milkshake followed by an ad libitum ice cream "taste test."

RESULTS

Body weight, body mass index, resting energy expenditure, and fasting leptin levels were very similar between restrained and unrestrained twins. In a preload study, twins ate similar amounts of ice cream shortly after drinking identical milkshakes (mean±SD; restrained 239±158 vs. unrestrained 228±132kcal; P=0.83). However, ghrelin concentrations during the preload study were significantly higher (P=0.03) in restrained twins than in their unrestrained co-twins. Regardless of restraint status, ghrelin levels prior to the preload study were prospectively and positively associated with ice cream intake (P=0.001).

CONCLUSIONS

Compared to their unrestrained co-twins, restrained twins had higher endogenous ghrelin levels during a preload study, but ate similar amounts. This finding is consistent with exertion of cognitive control relative to the state of physiologic appetite stimulation. Moreover, these findings in twins suggest that higher ghrelin levels result from restrained eating behavior and not from genetic predisposition.

Sex differences in the association between dietary restraint, insulin resistance and obesity

BACKGROUND & AIMS

Restrained food consumption may alter metabolic function and contribute to eventual weight gain; however, sex differences in these relationships have not been assessed. The objective of this study was to examine the relationship between restrained eating and insulin resistance and the influence of body mass index and sex on this relationship in a large community sample of both men and women. We hypothesized that restrained eating would be related to insulin resistance and this relationship would be influenced by sex and body mass index.

METHODS

In this cross-sectional, observational study, we studied 487 individuals from the community (men N = 222, women N = 265), who ranged from lean (body mass index 18.5-24.9 kg/m(2), N = 173), overweight (body mass index 25-29.9 kg/m(2), N = 159) to obese (body mass index >30 kg/m(2), N = 155) weight categories. We assessed restrained eating using the Dutch Eating Behavior Questionnaire and obtained fasting morning plasma insulin and glucose on all subjects.

RESULTS

In men, but not in women, restrained eating was related to homeostatic model assessment of insulin resistance (HOMA-IR) (p < 0.0001). Furthermore, HOMA-IR was significantly higher in men who were high- versus low-restrained eaters (p = 0.0006).

CONCLUSIONS

This study is the first to report sex differences with regard to the relationship between restrained eating and insulin resistance. Our results suggest that high restrained eating is associated with insulin resistance in men but not in women.

Characteristics of individuals who report present and past weight loss behaviours: results from a Canadian university community

PURPOSE

To characterise individuals who reported present and past weight loss behaviours on psycho-behavioural factors known to influence body weight, e.g. overeating, dietary restriction.

METHODS

An online questionnaire was distributed to a university community. Questions pertaining to present weight loss, previous weight loss, eating behaviour tendencies, perceived stress and sleep quality were answered by 3,069 individuals. Body weight and height were self-reported.

RESULTS

Present and past weight loss behaviours were prevalent in the sample, with 33.3 % of the participants who reported trying to lose weight, 33.1 % who reported having previously lost weight (>10 lbs), and 18.8 % who reported repeated weight loss behaviour (i.e. present and past weight loss behaviours). Trying to lose weight and previous weight loss were both independently associated with increased risk for psycho-behavioural characteristics known to be associated with obesity, e.g. overeating tendencies, perceived stress, short sleep duration. This risk was particularly elevated among the underweight/normal-weight individuals who reported repeated weight loss behaviours. Indeed, adjusted odds ratios for reporting restrictive and overeating tendencies, perceived stress and short sleep for these individuals were significantly higher compared to their underweight/normal-weight peers who did not report repeated weight loss behaviours (adjusted odds ratios 4.7, 2.7, 1.8, and 1.8, respectively, p < 0.01 to <0.0001).

CONCLUSIONS

Normal-weight individuals reporting weight loss behaviours are characterised by a psycho-behaviour profile which may further increase their risk of weight gain.

Dieting and restrained eating as prospective predictors of weight gain

Research in normal weight individuals paradoxically suggests that measures of attempted eating restriction might represent robust predictors of weight gain. This review examined the extent to which measures of dieting (e.g., self-reported weight loss dieting in the past year) and dietary restraint (e.g., the Cognitive Restraint scale from the Three-Factor Eating Questionnaire) have prospectively predicted weight change. We located and reviewed 25 prospective studies containing 40 relevant comparisons. Studies were limited to those in which participants were non-obese (with a mean BMI between 18.5 and 30) and averaged at least 12 years old. Neither measure predicted future weight loss. Fifteen of the 20 comparisons (75%) that examined measures of dieting significantly predicted future weight gain whereas only 1 of 20 (5%) that examined restrained eating measures did so. Two plausible explanations for these findings are that: (1) dieters and restrained eaters do not differ in terms of an underlying proneness toward weight gain, but restrained eating represents a more effective means of preventing it; and (2) normal weight individuals who diet do so because they are resisting a powerful predisposition toward weight gain which dieting ultimately fails to prevent. Recent dieting in non-obese individuals may be a valuable proxy of susceptibility to weight gain. This easily assessed characteristic could identify individuals for whom obesity prevention interventions would be particularly appropriate.

Eating Motives and the Controversy over Dieting: Eating Less Than Needed versus Less Than Wanted

Anti-dieting sentiment has grown in recent years. Critics of restrained eating suggest that it evokes counter-regulatory responses that render it ineffective or even iatrogenic. However, restrained eaters are not in negative energy balance and overweight individuals show reduced eating problems when losing weight by dieting. A distinction is often drawn between physiological and psychological hunger, and neuroscience research has shown that there is a neurophysiological reality underlying this distinction. The brain has a homeostatic system (activated by energy deficits) and a hedonic system (activated by the presence of palatable food). The omnipresence of highly palatable food in the environment may chronically activate the hedonic appetite system, producing a need to actively restrain eating not just to lose weight but to avoid gaining it. Just as restricting energy intake below homeostatic needs produces physiological deprivation, restricting intake of palatable foods may produce "perceived deprivation" despite a state of energy balance. In summary, the motivation to eat more than one needs appears to be every bit as real, and perhaps every bit as powerful, as the motivation to eat when energy deprived.

Reducing excessive gestational weight gain: lessons from the weight control literature and avenues for future research

Excessive gestational weight gain is a prevalent problem and an independent predictor of future obesity in both mothers and offspring. Intervention research to prevent excessive gestational weight gain is still in its infancy but results to date have been quite modest. Research in weight control outside of pregnancy over the past 30 years has been more robust and identified several key components of effective programs, including use of caloric restriction, daily diet self-monitoring, self-weighing, behavior therapy and ongoing patient-provider contact. The aim of this article is to summarize intervention components shown to be effective in promoting successful weight control outside of pregnancy and explore potential applications in pregnancy. Available evidence suggests that the strategies shown to be effective for weight control outside of pregnancy may also promote better weight control in pregnancy, but several lines for future investigation remain.

Evidence-based guideline of the German Nutrition Society: carbohydrate intake and prevention of nutrition-related diseases

The relative contribution of nutrition-related chronic diseases to the total disease burden of the society and the health care costs has risen continuously over the last decades. Thus, there is an urgent necessity to better exploit the potential of dietary prevention of diseases. Carbohydrates play a major role in human nutrition - next to fat, carbohydrates are the second biggest group of energy-yielding nutrients. Obesity, type 2 diabetes mellitus, dyslipoproteinaemia, hypertension, metabolic syndrome, coronary heart disease and cancer are wide-spread diseases, in which carbohydrates could have a pathophysiologic relevance. Correspondingly, modification of carbohydrate intake could have a preventive potential. In the present evidence-based guideline of the German Nutrition Society, the potential role of carbohydrates in the primary prevention of the named diseases was judged systematically. The major findings were: a high carbohydrate intake at the expense of total fat and saturated fatty acids reduces the concentrations of total, LDL and HDL cholesterol. A high carbohydrate consumption at the expense of polyunsaturated fatty acids increases total and LDL cholesterol, but reduces HDL cholesterol. Regardless of the type of fat being replaced, a high carbohydrate intake promotes an increase in the triglyceride concentration. Furthermore, a high consumption of sugar-sweetened beverages increases the risk of obesity and type 2 diabetes mellitus, whereas a high dietary fibre intake, mainly from whole-grain products, reduces the risk of obesity, type 2 diabetes mellitus, dyslipoproteinaemia, cardiovascular disease and colorectal cancer at varying evidence levels. The practical consequences for current dietary recommendations are presented.

Eating attitudes and behaviours in elite Canadian athletes with a spinal cord injury

Athletes with a spinal cord injury (SCI) appear to have relatively modest energy requirements despite demanding training regimes. Virtually nothing is known about the factors which influence the energy intake of those with a SCI including food related attitudes and behaviours. Using a cross-sectional observational design, three aspects of eating attitudes were measured using the Three-Factor Eating Questionnaire (TFEQ) along with six days of self-reported dietary intake and anthropometrics. Between March 2007 and May 2009, a total of 32 Canadian athletes with a SCI (n=24 men, n=8 women) completed the study. The TFEQ scales showed a cognitive dietary restraint score of 10.8±4.7, disinhibition score of 2.8±1.8 and hunger score of 3.1±2.2. When the group was split into high and low restraint groups using a median of 11.5, no differences were detected in any of the absolute parameters of reported dietary intake although the higher restraint group had protein intakes account for a greater proportion of total energy. Those with higher restraint scores also had a relatively higher disinhibition score. While the cognitive dietary restraint scores for the women were similar to other able-bodied populations, the scores for men were higher than population norms from other studies. The scores for disinhibition and hunger were lower than reported ranges from able-bodied subjects. These athletes may be actively monitoring or limiting dietary intake to avoid the high prevalence of obesity associated with a SCI or perhaps to maintain an ideal body composition for their sport performance.

Mental contrasting of a dieting wish improves self-reported health behaviour

Mentally contrasting a desired future with present reality standing in its way promotes commitment to feasible goals, whereas mentally indulging in a desired future does not. Dieting students (N = 134) reported their most important dieting wish that they deemed attainable within a 2-week period. Then, they were directed to mentally contrast or indulge in thoughts and images about the named dieting wish. A control condition was given no directions. Two weeks after the experiment, dieters retrospectively rated their behaviour change: in the mental contrasting condition they reported having eaten relatively fewer calories overall, fewer high-calorie food and more low-calorie food compared to those in the indulging and control conditions, and they also reported having been more physically active. This transfer effect from one health domain to another suggests a more generalised effect of mental contrasting versus indulging and control than previously assumed.

Food reinforcement and obesity. Psychological moderators

The relative reinforcing value of food (RRV(food)) provides an index of the motivation to eat. Research has shown that RRV(food) is higher in obese individuals than their non-obese peers, is associated with greater energy intake, predicts weight gain and interacts with impulsivity to predict energy intake. This study was designed to determine whether dietary restraint, dietary disinhibition or hunger moderate the effect of RRV(food) on the weight status and energy intake in 273 adults of various body mass index (BMI) levels. Hierarchical regression was used to assess the independent effects of RRV(food) on BMI and energy intake, controlling for age, sex, income, education, minority status, and RRV(reading). Results showed that greater RRV(food), but not RRV(reading), was associated with greater BMI and energy intake. Dietary disinhibition and dietary restraint moderated the relationship between RRV(food) and BMI, with dietary disinhibition being a stronger moderator of this relationship (r(2)=0.20) than dietary restraint (r(2)=0.095). In addition, dietary disinhibition moderated the effect of RRV(food) on energy intake. These results replicate the importance of RRV(food) as a predictor of obesity, and show that psychological factors moderate the effect of food reinforcement on body weight and energy intake. This trial was registered at clinicaltrials.gov as NCT00962117.

Relation of dietary restraint scores to activation of reward-related brain regions in response to food intake, anticipated intake, and food pictures

Prospective studies indicate that individuals with elevated dietary restraint scores are at increased risk for future bulimic symptom onset, suggesting that these individuals may show hyper-responsivity of reward regions to food and food cues. Thus, we used functional magnetic resonance imaging (fMRI) to examine the relation of dietary restraint scores to activation of reward-related brain regions in response to receipt and anticipated receipt of chocolate milkshake and exposure to pictures of appetizing foods in 39 female adolescents (mean age=15.5 ± 0.94). Dietary restraint scores were positively correlated with activation in the right orbitofrontal cortex (OFC) and bilateral dorsolateral prefrontal cortex (DLPFC) in response to milkshake receipt. However, dietary restraint scores did not correlate with activation in response to anticipated milkshake receipt or exposure to food pictures. Results indicate that individuals who report high dietary restraint have a hyper-responsivity in reward-related brain regions when food intake is occurring, which may increase risk for overeating and binge eating.

Cognitive biases to healthy and unhealthy food words predict change in BMI

The current study explored the predictive value of cognitive biases to food cues (assessed by emotional Stroop and dot probe tasks) on weight change over a 1-year period. This was a longitudinal study with undergraduate students (N = 102) living in shared student accommodation. After controlling for the effects of variables associated with weight (e.g., physical activity, stress, restrained eating, external eating, and emotional eating), no effects of cognitive bias were found with the dot probe. However, for the emotional Stroop, cognitive bias to unhealthy foods predicted an increase in BMI whereas cognitive bias to healthy foods was associated with a decrease in BMI. Results parallel findings in substance abuse research; cognitive biases appear to predict behavior change. Accordingly, future research should consider strategies for attentional retraining, encouraging individuals to reorient attention away from unhealthy eating cues.

Lifestyle factors and other health measures in a Canadian university community

With the increasing prevalence of obesity, there is a continuous search for effective obesity-prevention and health-promotion interventions. These interventions should be based on factors that have the potential to influence body weight and health. This study describes various health-related factors in a Canadian university community with the aim of developing more specific obesity interventions. A total of 3143 individuals completed an online questionnaire made up of 3 sections--on physical activity (PA), food habits, and other relevant lifestyle factors. The sampling error was +/-3.3% with a 95% confidence interval. Results showed that 22.9% of students and 37.3% of staff members were either overweight or obese. Students had less desirable eating patterns than staff members in terms of fish, energy drink, and regular milk product intake, and both groups reported undesirable breakfast consumption and quality. Nevertheless, results also showed that a high percentage of individuals in both groups did not meet the recommendations for vegetable, fruit, and fish intake, or PA. Only a few gender differences were observed in eating habits. Soft drink and energy drink consumption was higher and breakfast consumption was lower in men, whereas a higher percentage of women did not meet the recommendations for vegetable, fruit, or fish consumption. Dieting behaviours, disinhibition susceptibility, and moderate-intensity (MIPA) were the 3 lifestyle factors most highly associated with overweight and obesity in both groups. Results also suggest that female students were highly preoccupied with their body weight. This study shows that overweight and obesity are problems in a university community, and that they are associated with many health-related lifestyle behaviours. Although most of the lifestyle factors and health measures examined are similar across groups and genders, some differences call for the development of health-promotion programs with specific targeting strategies.

Impact of restraint and disinhibition on PYY plasma levels and subjective feelings of appetite

The impact of eating behaviours on circulating levels of appetite-regulating hormones remains largely unknown. The aims of this study were to assess the role of restraint and disinhibition on fasting/postprandial peptide YY (PYY) plasma levels and subjective feelings of appetite in normal-weight individuals and to determine whether the effect was energy load dependent. 33 participants (12 men) were classified as restrained/unrestrained and low/high in disinhibition based on Three Factor Eating Questionnaire-18R and Dutch Eating Behaviour Questionnaire. The impact of restraint/disinhibition on PYY plasma levels and feelings of appetite was measured, after a 500kcal and 1000kcal breakfast, using a randomised crossover design. Restraint did not impact on either fasting or postprandial PYY plasma levels, but participants with high disinhibition had a tendency towards a blunted postprandial PYY response. Moreover, restrained eaters reported lower ratings of prospective food consumption postprandially, and a tendency towards higher fullness/lower hunger. In conclusion, circulating PYY is unaffected by restrained eating behaviour, despite being associated with increased fullness and reduced hunger in the fed state. High levels of disinhibition tend to be associated with a blunted PYY response and this may contribute towards the susceptibility to overconsumption and increased risk of weight gain characteristic of this trait.

The association of restrained eating with weight change over time in a community-based sample of twins

We investigated the association of restrained eating with BMI and weight gain while controlling for the influence of genes and shared environment. Participants were 1,587 twins enrolled in the University of Washington Twin Registry (UWTR). Restrained eating was assessed by the Herman and Polivy Restraint Scale. Height and weight were self-reported on two occasions. Analyses used generalized estimating equations or multiple linear regression techniques. Restraint Scale scores were positively associated with both BMI (adjusted beta = 0.39 kg/m(2); 95% confidence interval (CI) = 0.34-0.44; P < 0.001) and weight gain (adjusted beta = 0.33 pounds; 95% CI = 0.17-0.49; P < 0.001). High Restraint Scale scorers had an adjusted mean BMI of 27.9 kg/m(2) (95% CI = 27.4-28.4) as compared to intermediate (mean = 25.5 kg/m(2); 95% CI = 25.2-25.8) and low scorers (mean = 23.0 kg/m(2); 95% CI = 22.7-23.3). In within-pair analyses among 598 same-sex twin pairs, the adjusted association between Restraint Scale scores and BMI persisted even when genetic and shared environmental factors were controlled for (adjusted beta = 0.18; 95% CI = 0.12-0.24; P < 0.001), as did the association with weight gain (adjusted beta = 0.37; 95% CI = 0.13-0.61; P = 0.003). In stratified analyses, dizygotic (DZ) twins differed more in BMI for a given difference in the Restraint Scale score than monozygotic (MZ) twins, for whom genetics are 100% controlled (adjusted beta = 0.32; 95% CI = 0.20-0.44 vs. adjusted beta = 0.10; 95% CI = 0.04-0.16; P = 0.001 for test of interaction). These data demonstrate that observed relationships between BMI, weight gain, and restrained eating, as assessed by the Restraint Scale, have a strong environmental influence and are not solely due to shared genetic factors.

Gender Differences in Depressive Symptoms During Adolescence: The Contributions of Weight-Related Concerns and Behaviors

A theoretical model of gender differences in depressive symptoms during adolescence was evaluated using data from Waves I and II of the National Longitudinal Study of Adolescent Health. The theoretical model under examination was primarily informed by the gender-additive model of gender differences in depressive symptoms during adolescence proposed by Stice and Bearman (2001). In the model, it was posited that BMI would be associated with perceiving oneself as overweight, which would then lead to a higher probability of dieting, which would be associated with greater depressive symptoms. Participants were 10,864 male and female adolescents. Gender did not moderate any of the model pathways, but mediation analysis indicated that gender differences in changes in depressive symptoms were mediated by perceived weight status and dieting. Findings suggest that one explanation for girls' higher depressive symptoms in adolescence relative to boys is girls' greater tendencies to perceive themselves as overweight and to diet.

Risk factors and prodromal eating pathology

Prospective studies have identified factors that increase risk for eating pathology onset, including perceived pressure for thinness, thin-ideal internalization, body dissatisfaction, dietary restraint, and negative affect. Research also suggests that body dissatisfaction and dietary restraint may constitute prodromal stages of the development of eating disorders. Prevention trials indicate that interventions that reduce pressure to be thin, thin-ideal internalization, body dissatisfaction, and negative affect significantly reduce eating disorder symptoms. Further, there is evidence that selective prevention programs that target young women at elevated risk for eating pathology by virtue of thin-ideal internalization, body dissatisfaction, and negative affect produce significant larger intervention effects than do universal programs offered to unselected populations. Thus, research on risk factors and prodromal stages of eating pathology has assisted in the design of efficacious prevention programs and the identification of high-risk individuals to target with these interventions; additional research in this area may lead to even more effective prevention programs.

Change in eating and body related behaviors during the first year of university

Significant changes in BMI, disordered eating, and body image dissatisfaction occur during the first year of university. However, previous research has not yet isolated the key factors that lead to these changes. This study sought to add to the body of research in this area by investigating students' eating attitudes, behaviors, body image, and weight at the beginning and the end of the first year of university. Participants were initially 64 male and female university students from two universities: one rural and one urban. Twenty-eight percent of the participants completed assessments at two time points. These included a series of questionnaires designed to measure disordered eating, body image dissatisfaction and weight. These changes were different for males and females. Substantial changes in eating behaviors, attitudes, body image and BMI occur during the first year of university. Concrete knowledge about these changes might help students adapt to university life.