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

Virtual reality assessment of a high-calorie food bias: Replication and food-specificity in healthy participants

BACKGROUND

Theoretical models and behavioural studies indicate faster approach behaviour for high-calorie food (approach bias) among healthy participants. A previous study with Virtual Reality (VR) and online motion-capture quantified this approach bias towards food and non-food cues in a controlled VR environment with hand movements. The aim of this study was to test the specificity of a manual approach bias for high-calorie food in grasp movements compared to low-calorie food and neutral objects of different complexity, namely, simple balls and geometrically more complex office tools.

METHODS

In a VR setting, healthy participants (N = 27) repeatedly grasped or pushed high-calorie food, low-calorie food, balls and office tools in randomized order with 30 item repetitions. All objects were rated for valence and arousal.

RESULTS

High-calorie food was less attractive and more arousing in subjective ratings than low-calorie food and neutral objects. Movement onset was faster for high-calorie food in push-trials, but overall push responses were comparable. In contrast, responses to high-calorie food relative to low-calorie food and to control objects were faster in grasp trials for later stages of interaction (grasp and collect). Non-parametric tests confirmed an approach bias for high-calorie food.

CONCLUSION

A behavioural bias for food was specific to high-calorie food objects. The results confirm the presence of bottom-up advantages in motor-cognitive behaviour for high-calorie food in a non-clinical population. More systematic variations of object fidelity and in clinical populations are outstanding. The utility of VR in assessing approach behaviour is confirmed in this study by exploring manual interactions in a controlled environment.

Beneficial effects of time-restricted fasting on cardiovascular disease risk factors: a meta-analysis

BACKGROUND

Cardiovascular disease continues to be a leading cause of mortality worldwide, highlighting the need to explore innovative approaches to improve cardiovascular health outcomes. Time-restricted fasting (TRF) is a dietary intervention that involves limiting the time window for food consumption. It has gained attention for its potential benefits on metabolic health and weight management. This study aims to investigate the impact of TRF on key risk factors, including body weight, glucose metabolism, blood pressure, and lipid profile.

METHODS

We conducted a systematic search in five databases (Scopus, Embase, PubMed, Cochrane, and Web of Science) for relevant studies up to January 2023. After applying inclusion criteria, 12 studies were eligible for analysis. Quality assessment was conducted using the ROB-2.0 tool and ROBINS-I. Risk of bias was mapped using Revman 5.3, and data analysis included Hartung-Knapp adjustment using R 4.2.2.

RESULTS

The group that underwent the TRF intervention exhibited a significant decrease in body weight (SMD: -0.22; 95%CI: -0.41, -0.04; P < 0.05) and fat mass (SMD: -0.19; 95%CI: -0.36, -0.02; P < 0.05), while maintaining lean mass (SMD: -0.09; 95%CI: -0.08, 0.26; P > 0.05).

CONCLUSION

TRF has shown potential as a treatment strategy for reducing total body weight by targeting adipose tissue, with potential improvements in cardiometabolic function.

The Psychological Impact of the Widespread Availability of Palatable Foods Predicts Uncontrolled and Emotional Eating in Adults

This study aimed to investigate the role of the psychological impact of environments rich in palatable foods on three aspects of eating behavior: cognitive restraint (CR), uncontrolled eating (UE), and emotional eating (EE). The hypotheses were as follows: (a) The psychological impact (i.e., motivation to eat) of an environment rich in palatable foods will positively predict CR, UE, and EE; (b) dieting will predict CR, UE, and EE; and (c) CR, UE, and EE will positively predict body mass index (BMI). This study had a cross-sectional design in which data were collected online from 413 subjects. The psychological impact of food-rich environments (food available, food present, and food tasted) was assessed using the Power of Food Scale (PFS), and CR, UE, and EE were assessed using the Three-Factor Eating Questionnaire (TFEQ-R18). Both instruments were tested for confirmatory factor analysis. The relationship between constructs was measured using partial least-square structural equation modeling (PLS-SEM). "Food available" positively predicted all TFEQ-R18 factors (p < 0.01). "Food present" positively predicted UE (p < 0.001) and EE (p = 0.01). People currently on a diet showed higher levels of CR (p < 0.001) and EE (p = 0.02). UE and EE positively predicted BMI. Thus, CR, UE, and EE were positively predicted by the motivation to consume palatable foods in varying proximity, suggesting that the presence of food and, more importantly, its general availability may be important determinants of eating behavior, particularly UE and EE. Health strategies should consider the influence of the food environment to prevent and better manage impairments in eating behavior. Sex differences suggest that special attention should be paid to women. Furthermore, dieting was associated with higher levels of EE, which in turn was associated with higher BMI. Weight loss interventions should consider this vulnerability.

Analysis of a State Police Academy Menu Cycle for Dietary Quality and Performance Nutrition Adequacy

Law enforcement officers have high rates of overweight and obesity. With diet as a leading risk factor, training academies present an opportunity for early-career nutrition intervention. Our purpose was to determine the dietary quality (DQ) and performance nutrition adequacy of a state police academy's cafeteria menu. This cross-sectional content analysis included six weeks (three daily meals, Monday-Friday) of a police academy menu. Nutrient content was determined by portioning menus, gathering food specifications, and performing nutrient analysis. DQ was assessed using the Healthy Eating Index (HEI) 2015. Statistical analyses included independent t-tests and Cohen's d. The total HEI score was 54/100. Subcomponent scores indicating adequacy included added sugar (5/5), total protein (4.97/5) and whole fruits (4.77/5). Seafood/plant proteins (0.33/5), fatty acid ratio (1.31/5), and dairy scores (1.59/10) needed significant improvement. The menu met the recommended intake for 13 of 19 nutrients investigated. Nutrients that did not meet adequacy were calories (% mean difference, needs-menu = 36.7%), carbohydrates (52.3%), vitamins D (82.5%) and E (66.7%), magnesium (44.1%), and potassium (41.8%). The academy menu leaves room for improvement in DQ and shortfall nutrients. By increasing low scores, the overall DQ of the menu will increase and supplement missing nutrients.

The dynamic network associations of food craving, restrained eating, hunger and negative emotions

OBJECTIVE

Food craving, restrained eating, hunger, and negative emotions may predict and reinforce one another. However, less is known about how they interact together as a complex system in daily life. Therefore, we used a dynamic network approach to examine the associations between food craving, restrained eating, hunger and negative emotions in daily life.

METHODS

Food craving, restrained eating, hunger and negative emotions were measured using ecological momentary assessment three times a day over ten days in a community sample in Israel (n = 123). A two-step multilevel vector auto-regression network analysis was used to estimate temporal, contemporaneous and between-persons networks.

RESULTS

In the temporal network, restrained eating was the most central predictor of eating behaviors and negative emotions, predicting food craving and hunger as well as sadness and loneliness. Food craving was also predicted by hunger and stress, and hunger predicted loneliness. In the contemporaneous network, food craving was associated with hunger and feeling bored, and higher anger was associated with lower restrained eating. Stress and sadness were central negative emotions in the models.

DISCUSSION

This study suggests possible temporal and contemporaneous relationships between food craving, restrained eating, hunger and negative emotions, emphasizing their complex interactions in daily life. Restrained eating and stress should be investigated as potential targets for interventions addressing food craving and overeating.

Brain regulation of hunger and motivation: The case for integrating homeostatic and hedonic concepts and its implications for obesity and addiction

Obesity and other eating disorders are marked by dysregulations to brain metabolic, hedonic, motivational, and sensory systems that control food intake. Classic approaches in hunger research have distinguished between hedonic and homeostatic processes, and have mostly treated these systems as independent. Hindbrain structures and a complex network of interconnected hypothalamic nuclei control metabolic processes, energy expenditure, and food intake while mesocorticolimbic structures are though to control hedonic and motivational processes associated with food reward. However, it is becoming increasingly clear that hedonic and homeostatic brain systems do not function in isolation, but rather interact as part of a larger network that regulates food intake. Incentive theories of motivation provide a useful route to explore these interactions. Adapting incentive theories of motivation can enable researchers to better how motivational systems dysfunction during disease. Obesity and addiction are associated with profound alterations to both hedonic and homeostatic brain systems that result in maladaptive patterns of consumption. A subset of individuals with obesity may experience pathological cravings for food due to incentive sensitization of brain systems that generate excessive 'wanting' to eat. Further progress in understanding how the brain regulates hunger and appetite may depend on merging traditional hedonic and homeostatic concepts of food reward and motivation.

The Rise and Fall of Physiological Theories of the Control of Human Eating Behavior

Kuhns was the first to suggest that theories in science do not develop in small increments but rather in major leaps to paradigms that examine the same question through very different perspectives. Theories on the mechanism responsible for control of human food intake fall into Kuhn’s description. This article describes how the two major theories of the control of food intake in humans, the Glucostatic Theory, and the Lipostatic Theory, showed initial promise as explanations, but later deteriorated with the slow accumulation experimental data. The locus of theories considered eating behavior as a part of physiological system that regulates the storage of energy on the body. We challenge this fundamental belief with data which suggests that we must be ready to accept a major change in the way we think about eating behavior if we are ever to decrease the prevalence of obesity.

Food Captures Attention, but Not the Eyes: An Eye-Tracking Study on Mindset and BMI’s Impact on Attentional Capture by High-Caloric Visual Food Stimuli

Obesity is a worldwide pandemic and theories propose that attentional bias (AB) for food triggers craving and overeating, especially for people with obesity. However, empirical evidence is inconsistent, which may be due to methodological diversity and the double-sided nature of high-caloric palatable foods. That is, these foods simultaneously have a high hedonic and a low health value. So, depending on context and/or emotional state, people’s mindset while viewing foods may alternate between hedonic (taste) and health (calories) values, possibly affecting AB for food in opposite directions. This study tests how mindset and BMI (Body Mass Index) influences AB and food intake. We expect greater AB for food and more food intake in the hedonic compared to the health mindset, especially for people with obesity. Mindsets were induced using short video-clips in two sessions in counterbalanced order. Participants (35 with a healthy-weight-category BMI, 31 with obesity) performed a modified Additional Singleton paradigm where they searched for a neutral target among neutral fillers. On 90% of the trials, either a food or a neutral distractor appeared. Response latencies to the target and eye-movements to the distractor were recorded. Dependent variables included: response latencies, and eye-movement variables on the distractor: fixations (%), 1st fixation duration, dwell-time. Food intake was assessed in a bogus taste test. No significant effects emerged from the eye-movements analysis, whereas the analysis of response latencies showed an AB for food, not significantly moderated by BMI or mindset. Food intake was affected by mindset partly as expected, as participants ate more in the hedonic than in the health mindset when the hedonic mindset was induced in the second session. One AB measure (fixations) correlated positively with food intake. Finally, food captured attention – but not the eyes – and mindset affects food intake partly as expected.

Validity and reliability of the Dietary Rules Inventory (DRI)

BACKGROUND

Dietary rules are common in patients with eating disorders, and according to transdiagnostic cognitive behavioural theory for eating disorders, represent a key behaviour maintaining eating-disorder psychopathology. The aim of this study was to describe the design and validation of the Dietary Rules Inventory (DRI), a new self-report questionnaire that assesses dietary rules in patients with eating disorders.

METHODS

A transdiagnostic sample of 320 patients with eating disorders, as well as 95 patients with obesity and 122 healthy controls were recruited. Patients with eating disorders also completed the Dutch Eating Behaviour Questionnaire (DEBQ), the Eating Disorder Examination Questionnaire, the Brief Symptoms Inventory and the Clinical Impairment Assessment. Dietary rules were rated on a continuous Likert-type scale (0-4), rating how often (from never to always) they had been applied over the previous 28 days.

RESULTS

DRI scores were significantly higher in patients with eating disorders than in patients with obesity and healthy controls. Principal factor analysis identified that 55.8% of the variance was accounted for by four factors, namely 'what to eat', 'social eating', 'when and how much to eat' and 'caloric level'. Both global score and subscales demonstrated high internal and test-retest reliability. The DRI global score was significantly correlated with the DEBQ 'restrained eating' subscale, as well as eating-disorder and general psychopathology and clinical impairment scores, demonstrating good convergent validity.

CONCLUSIONS

These findings suggest that the DRI is a valid self-report questionnaire that may provide important clinical information regarding the dietary rules underlying dietary restraint in patients with eating disorders.

LEVEL OF EVIDENCE

V, descriptive study.

Persistence: A key factor in understanding the circumstances under which dietary restraint predicts restriction of caloric intake

Dietary restraint refers to the intention to restrict caloric intake, whereas dietary restriction refers to the actual intentional and sustained restriction of caloric intake for weight-control purposes. Findings regarding the relation between dietary restraint and restriction to date are inconsistent. Our study sought to clarify this complex relationship using a novel laboratory task. Participants (N = 103; 56.3% female) completed a Paced Visual Serial Addition Task (PVSAT). Participants were provided a choice between ending each of eight PVSAT rounds at any time and drinking a high-calorie Kool-Aid® mixture or correctly completing 10 consecutive computations to access to a zero-calorie mixture for each round. We measured participants' dietary restraint using the Three-Factor Eating Questionnaire - Restraint Subscale and measured persistence and dietary restriction using the PVSAT. Results indicated a positive association between persistence and restriction. Female participants demonstrated higher eating disorder psychopathology, dietary restraint, and dietary restriction compared to male participants. Restraint was positively associated with restriction the more individuals persisted, indicating that persistence is a potentially important modifier of the relation between dietary restraint and restriction. Our findings highlight the complexity of the relation between dietary restraint and restriction; that is, measures of dietary restraint alone may not reliably predict short-term dietary restriction during laboratory consumption tasks; however, other factors, such as persistence, may play critical roles.

Eating Behaviour among University Students: Relationships with Age, Socioeconomic Status, Physical Activity, Body Mass Index, Waist-to-Height Ratio and Social Desirability

Eating behaviour is of particular interest for research focusing on body weight status. However, little is known about the relationships of certain factors, especially social desirability, with self-reported eating behaviour such as cognitive restraint, uncontrolled eating, and emotional eating among young adult males and females. This study aimed to evaluate the relationships between eating behaviour and age, socioeconomic status (SES), physical activity (PA), body mass index (BMI), waist-to-height ratio (WHtR), and social desirability among university students. A cross-sectional study was conducted among 353 university students (59.2% females). Eating behaviour was assessed using the 13-item Three-Factor Eating Questionnaire (TFEQ-13). SES and PA were determined using self-reporting, and the Marlowe–Crowne Social Desirability Scale assessed social desirability. BMI and WHtR were calculated based on measured parameters. Associations between self-reported eating behaviour and other variables were assessed using Pearson’s correlation coefficient and multivariate general linear models. Cognitive restraint was positively correlated with BMI and WHtR in both males (r = 0.174, P = 0.036 and r = 0.194, P = 0.020, respectively) and females (r = 0.239, P < 0.001 and r = 0.165, P = 0.017, respectively), and emotional eating was positively correlated with BMI among females (r = 0.184, P = 0.008). Social desirability was negatively correlated with uncontrolled eating (r = −0.287, P < 0.001) and emotional eating (r = −0.301, P < 0.001) among females. There were no significant correlations between eating behaviour and age or socioeconomic status (P > 0.05). Multivariate analysis showed that, among males, PA had a main effect on emotional eating (ηp² = 0.044, F = 6.276, P = 0.013). Among females, cognitive restraint was positively associated with PA (ηp² = 0.034, F = 7.127, P = 0.008) and BMI (ηp² = 0.038, F = 7.959, P = 0.005), and emotional eating with BMI (ηp² = 0.032, F = 6.638, P = 0.011). Social desirability had the highest main effect on eating behaviour among females, being negatively associated with uncontrolled eating (ηp² = 0.077, F = 16.754, P < 0.001) and emotional eating (ηp² = 0.082, F = 18.046, P < 0.001). This study showed that PA, BMI, WHtR, and social desirability were associated with self-reported eating behaviour among university students. Social desirability bias should be considered when evaluating uncontrolled eating and emotional eating among females.

A meta-analysis of the relationship between eating restraint, impaired cognitive control and cognitive bias to food in non-clinical samples

AIM

Food restriction is argued to be a precursor for unhealthy preoccupation with food, possibly leading to the development of an eating disorder. We updated previous meta-analyses that examined the relationship between eating restraint and deficits in either general or food-related attentional and inhibitory control. We hypothesized that inconsistencies in the literature around eating restraint, impaired cognitive control, impulsivity and cognitive biases for food could be attributed to the scale used to measure eating restraint.

METHOD

A (preregistered) subgroup meta-analysis examined whether patterns of impaired cognitive control and cognitive bias for food in predominantly healthy (non-clinical) samples differed as a function of the scale used to measure eating restraint. A series of exploratory meta-analyses were carried out for specific attentional bias tasks. In total 57 datasets were included.

RESULTS

The subgroup analysis did not provide evidence that the relationship between eating restraint and impaired or biased cognitions differed significantly as a function of restraint scale. Heterogeneity across studies was high. When examining specific attentional bias tasks there was no evidence that increased eating restraint was associated with increased attentional bias or distraction by food cues, regardless of which scale was used to measure eating restraint.

CONCLUSIONS

There is little experimental evidence for the common narrative that increased eating restraint is related to impaired cognitive control generally or increased cognitive bias for food, in non-clinical samples.

The Relationship between Adults' Perceptions, Attitudes of COVID-19, Intuitive Eating, and Mindful Eating Behaviors

In total, 1224 Turkish adults (27.5 ± 9.6 years; 80.6% female) answered sociodemographic questions, and three instruments: Mindful Eating Questionnaire (MEQ), Intuitive Eating Scale-2 (IES-2), and COVID-19 Perception and Attitude Scale. Women's perceptions and attitudes toward COVID-19 indicated higher concerns than men (p < .001). It was found that IES-2 scores of all subjects increased as body mass index (BMI) decreased and education level increased (p < .001; p = .033, respectively). During the social isolation of COVID-19, the MEQ scores of married couples and those who did not eat take-out foods were higher (p = .027; p = .006, respectively). Interestingly, it was found that as the BMI of the subjects increased, their MEQ scores increased (p < .001). The COVID-19 pandemic, which has social and economic consequences, has a great impact on human health and causes sudden lifestyle changes through social distance and isolation at home. Although social isolation during the epidemic is a necessary precaution to protect public health, the results of this study support that it causes changes in intuitive eating, and mindful eating behaviors.

Randomized Trial Examining the Effect of a 12-wk Exercise Program on Hedonic Eating

PURPOSE

This efficacy trial tests the hypothesis that exercise training favorably affects hedonic eating (i.e., overeating, stress-induced overeating, disinhibited eating, eating when tempted), in a sample of women who are overweight or obese.

METHODS

Participants were inactive at baseline, self-identified as "stress eaters," and were randomized to 12 wk of moderate-intensity exercise training (EX; combination of supervised and objectively confirmed unsupervised sessions) or to a no-exercise control condition (CON). EX participants were given an exercise goal of 200 min·wk-1. No dietary instructions or weight control strategies were provided. Assessments occurred at baseline and 12 wk. Overeating episodes, stress-induced overeating, and dietary temptations were measured over 14 d at each assessment using ecological momentary assessment. Disinhibition and dietary restraint were assessed via a questionnaire.

RESULTS

Forty-nine participants (age, 40.4 ± 10.8 yr; body mass index, 32.4 ± 4.1 kg·m-2) enrolled, and 39 completed this study. Adherence to the exercise intervention was high (99.4% of all prescribed exercise). At week 12, the proportion of eating episodes that were characterized as overeating episodes was lower in EX versus CON (21.98% in EX vs 26.62% in control; P = 0.001). Disinhibition decreased in EX but not in CON (P = 0.02) and was driven by internal factors. There was a trend such that CON was more likely to give into dietary temptations (P = 0.08). Stress-induced overeating was low and did not differ between conditions (P = 0.61).

CONCLUSIONS

Exercise training reduced the likelihood of overeating and eating in response to internal cues in women who self-identified as stress eaters. This may be one pathway by which exercise affects body weight.

The food restriction wars: Proposed resolution of a primary battle

Research regarding the definition and consequences of dieting has generated controversy for years. This controversy has spilled over into the public domain, especially as eating disorders and obesity have become more prevalent. One of the earliest and longest-lasting controversies involves the restrained eating framework, which was originally developed by Herman and Polivy and also strongly influenced the development of the cognitive-behavioral model of bulimia nervosa. An alternative framework for understanding the role of dieting in nonclinical and clinical groups, called the Three-Factor Model of Dieting, took a sharply different approach to defining, and understanding the impact of, dieting. This paper provides a brief historical review of the development of these divergent perspectives and updates the Three Factor Model's critical distinction between restraining eating to prevent over-consumption and dieting to lose weight. We suggest that three historical trends impacted the development of Restraint Theory in ways that unfairly impugned dieting for weight control: the emergence of the new eating disorders of bulimia nervosa and binge eating disorder, a population-based increase in loss of control eating and a population-based increase in obesity. This update is aimed in part at encouraging new research to reconcile ongoing, unresolved issues between Herman and Polivy's restrained eating model and the Three-Factor model of Dieting model. Such research might also contribute to the public's understanding of the pros and cons of dieting and to new approaches to treating eating disorders and obesity.

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.

Perspective: Time-Restricted Eating Compared with Caloric Restriction: Potential Facilitators and Barriers of Long-Term Weight Loss Maintenance

A growing body of literature examines the potential benefits of a time-based diet strategy referred to as time-restricted eating (TRE). TRE, a type of intermittent fasting, restricts the time of eating to a window of 4-12 h/d but allows ad libitum intake during eating windows. Although TRE diets do not overtly attempt to reduce energy intake, preliminary evidence from small studies suggests that TRE can lead to concomitant reduction in total energy, improvements in metabolic health, and weight loss. Unique features of the TRE diet strategy may facilitate adherence and long-term weight loss maintenance. In this Perspective, we explore the potential multilevel (i.e., biological, behavioral, psychosocial, environmental) facilitators and barriers of TRE for long-term weight loss maintenance in comparison with the more commonly used diet strategy, caloric restriction (CR). Compared with CR, TRE may facilitate weight loss maintenance by counteracting physiological adaptations to weight loss (biological), allowing for usual dietary preferences to be maintained (behavioral), preserving executive functioning (psychosocial), and enabling individuals to withstand situational pressures to overeat (environmental). However, TRE may also pose unique barriers to weight loss maintenance, particularly for individuals with poor baseline diet quality, internal or social pressures to eat outside selected windows (e.g., grazers), and competing demands that interfere with the scheduling of eating. Future studies of TRE in free-living individuals should consider the multiple levels of influence impacting long-term adherence and weight loss maintenance. Ultimately, TRE could be one strategy in a toolkit of tailored diet strategies to support metabolic health and weight loss maintenance.

Commentary on: "What is restrained eating and how do we identify it?": Unveiling the elephant in the room

This paper is a commentary on Polivy, Herman and Mills' (2020) article, entitled "What is restrained eating and how do we identify it?". Polivy et al.'s paper makes a useful contribution by providing guidelines to researchers for choosing the most appropriate measure of restraint for their research questions. However, the authors assume that restrained eating can be appropriately conceptualized as a trait, an assumption I question. They also assume that restrained eating has a causal influence on the outcomes (e.g., counterregulatory eating, negative affect eating, binge eating) with which it has been associated, which I also question. Finally, they ignored a second prominent model for conceptualizing dieting behavior, the Three-Factor Model of Dieting. The Three-Factor Model decomposes the construct of restrained eating into two types of dieting (current weight loss dieting and weight suppression) that do appear to be causally related to eating control and one type (restrained eating to avoid excessive consumption) that modulates likelihood of overeating but does not cause it. I conclude by noting that scientific progress is best served by promoting, not avoiding, discussion and debate about a multiplicity of perspectives on topics of interest, especially when incompatible hypotheses and data exist on such topics.

The Relationship between Restrained Eating, Body Image, and Dietary Intake among University Students in China: A Cross-Sectional Study

This study aims to explore the association between restrained eating, body image, and dietary intake among Chinese college students. This cross-sectional study included 1301 college students at two universities in Hunan Province. Electronic questionnaires were used to collect information including students’ demographic characteristics, restrained eating, perception of body weight, body satisfaction, and dietary intake. Anthropometric measurements were collected to calculate body mass index (BMI). The prevalence of high restrained eating was 52.8%. Students who were dissatisfied with their bodies or overestimated their body weight showed a higher tendency toward high restrained eating (p < 0.05). Students with high restrained eating tended to eat fruits and eggs more frequently, while the frequency of eating domestic animals and poultry, sugar-sweetened beverages, and fast food were the opposite. Moreover, high restrained eating was a risk factor for low dietary diversity (odds ratio (OR) = 1.384, 95% confidence interval: 1.002~1.912). The high incidence of restrained eating among Chinese college students and its energy-restricted diets that may lead to possible health implications require attention. Further studies are needed to investigate the characteristics of college students’ restrained eating to tailor appropriate interventions for forming positive body images and promoting healthy eating behaviors, thus, improving dietary quality.

Modeling of food intake among restrained and unrestrained eaters

The Theory of Normal Eating suggests that how much others eat sets an upper limit for how much it is appropriate to eat. This study tested the hypothesis that restrained eaters, who typically eat less than they want to, would be more responsive to a high-intake norm than would unrestrained eaters. Data were combined from 8 experimental studies (total N = 735 female participants; 305 restrained eaters, 430 unrestrained eaters). Each study: (a) included a low-intake norm, a high-intake norm, and a no-norm control condition; (b) measured participants' food intake; and (c) included the Restraint Scale as a measure of dietary restraint. There were no differences between restrained unrestrained eaters in the no-norm control condition or in the magnitude of the inhibition effect (i.e., the difference between the low-intake norm condition and the control condition). There was, however, a restraint difference in the magnitude of the augmentation effect (i.e., the difference between the high-intake norm condition and the control condition). Restrained eaters showed a larger augmentation effect (d = 0.58; 95% CI = 0.29, 0.87) than did unrestrained eaters (d = 0.20; 95% CI = -0.05, 0.45). Social norms provide an upper limit for acceptable food intake, with high-intake norms permitting (but not requiring) individuals to indulge themselves. The fact that restrained eaters were more responsive to the high-intake norm than were unrestrained eaters suggests that the high-intake norm gives restrained eaters permission to indulge when they typically eat less than they want to.

Cognitive Restructuring vs. Defusion: Impact on craving, healthy and unhealthy food intake

Coping with food cravings is crucial for weight management. Individuals tend to use avoidance strategies to resist food cravings and prevent overeating, but such strategies may not result in the benefits sought. This study compared the effects of two cognitive techniques (Restructuring vs. Defusion) for dealing with food cravings in terms of their impact on healthy vs. unhealthy eating behavior (i.e., consumption of chocolate and/or carrots following the intervention). Sixty-five participants (M_age = 19.65 years) received either a 30-minute face-to-face instruction on cognitive restructuring (CR) or cognitive defusion (CD) along with 15 min of practice, or 45 min of obesity education and discussion (control). To examine craving and eating choices following the intervention, participants received bags of chocolate and carrots and were asked to carry these with them at all times over the next week, exchanging the bags every 2 days. Participants in the CD group ate fewer chocolates (M = 11.74) compared to CR (M = 17.06) and Control groups (M = 29.18) during the experimental week. The groups did not differ in number of carrot pieces eaten, though the CD group ate more carrots than chocolates. CD resulted in fewer self-reported cravings compared to CR and CO groups. At a final taste test, both CD and CR groups ate significantly fewer chocolates compared to the CO group. CD appears to be an effective technique in managing food craving and to present some advantages over CR.

Food Reward and Food Choice. An Inquiry Through The Liking and Wanting Model

What if consumers are getting obese because eating less calories is more difficult for persons that have a higher pleasure and desire towards food (Ikeda et al., 2005) and food companies do not help given only a two extreme option choice to satisfy their needs (i.e., low calories vs. high calories or healthy vs. unhealthy)? Reward systems are being described with a new conceptual approach where liking—the pleasure derived from eating a given food—and wanting—motivational value, desire, or craving—can be seen as the significant forces guiding eating behavior. Our work shows that pleasure (liking), desire (wanting), and the interaction between them influence and are good predictors of food choice and food intake. Reward responses to food are closely linked to food choice, inducing to caloric overconsumption. Based on the responses given to a self-administered questionnaire measuring liking and wanting attitudes, we found three different segments named ‘Reward lovers,’ ‘Half epicurious,’ and ‘Non indulgents’. Their behavior when choosing food is quite different. Results show differential effects on caloric consumption depending on segments. The introduction of more food choices that try to balance their content is a win-win strategy for consumers, companies, and society.

How dieting might make some fatter: modeling weight cycling toward obesity from a perspective of body composition autoregulation

The notion that dieting makes some people fatter has in the past decade gained considerable interest from both epidemiological predictions and biological plausibility. Several large-scale prospective studies have suggested that dieting to lose weight is associated with future weight gain and obesity, with such predictions being stronger and more consistent among dieters who are in the normal range of body weight rather than in those with obesity. Furthermore, the biological plausibility that dieting predisposes people who are lean (rather than those with overweight or obesity) to regain more body fat than what had been lost (referred to as fat overshooting) has recently gained support from a re-analysis of data on body composition during weight loss and subsequent weight recovery from the classic longitudinal Minnesota Starvation Experiment. These have revealed an inverse exponential relationship between the amount of fat overshot and initial adiposity, and have suggested that a temporal desynchronization in the recoveries of fat and lean tissues, in turn residing in differences in lean-fat partitioning during weight loss vs. during weight recovery (with fat recovery faster than lean tissue recovery) is a cardinal feature of fat overshooting. Within a conceptual framework that integrates the relationship between post-dieting fat overshooting with initial adiposity, the extent of weight loss and the differential lean-fat partitioning during weight loss vs. weight recovery, we describe here a mathematical model of weight cycling to predict the excess fat that could be gained through repeated dieting and multiple weight cycles from a standpoint of body composition autoregulation.

Psychometric properties of Power of Food Scale in Iranian adult population: gender-related differences in hedonic hunger

PURPOSE

The present study was performed to develop the Persian version of Power of Food Scale (PFS) questionnaire (PFS-P) and to assess the hedonic hunger in Iranian adult population. In addition, associations between individual differences, including sex and body mass index (BMI) and the appetitive motives measured by the PFS-P were assessed.

METHODS

Eight hundred and twenty participants were studied. The PFS-P, the International Physical Activity Questionnaire, the Three-Factor Eating Questionnaire, and a questionnaire pertaining to demographic characteristics were completed for all participants.

RESULTS

The Cronbach's alpha values for the factors "food available", "food present" and "food taste" were 0.87, 0.85, and 0.78, respectively. The intraclass correlation coefficient ranged from 0.80 to 0.97 for the factors of PFS-P. Good content, face, criterion, and construct validity were observed for the PFS-P. In addition, a good reliability was found for both aggregate score of the PFS-P and the scores of its three factors. Relatively strong associations were found between BMI and the PFS-P score (r = 0.43). The hedonic hunger was significantly higher in women than men (p < 0.001).

CONCLUSIONS

The findings of the present study provide further evidence in support of the suitability of PFS as a valid instrument to measure hedonic hunger. PFS-P can be used as a valid and reliable measure to assess hedonic hunger in Iranian populations. In addition, a moderately strong correlation was observed between BMI and hedonic hunger scores. This study revealed that women may experience hedonic hunger more than men.

LEVEL OF EVIDENCE

Level V, cross-sectional descriptive study.

Rethinking Food Reward

The conscious perception of the hedonic sensory properties of caloric foods is commonly believed to guide our dietary choices. Current and traditional models implicate the consciously perceived hedonic qualities of food as driving overeating, whereas subliminal signals arising from the gut would curb our uncontrolled desire for calories. Here we review recent animal and human studies that support a markedly different model for food reward. These findings reveal in particular the existence of subcortical body-to-brain neural pathways linking gastrointestinal nutrient sensors to the brain's reward regions. Unexpectedly, consciously perceptible hedonic qualities appear to play a less relevant, and mostly transient, role in food reinforcement. In this model, gut-brain reward pathways bypass cranial taste and aroma sensory receptors and the cortical networks that give rise to flavor perception. They instead reinforce behaviors independently of the cognitive processes that support overt insights into the nature of our dietary decisions.

Relationships Among Dietary Cognitive Restraint, Food Preferences, and Reaction Times

Objective

To assess the associations between dietary cognitive restraint, disinhibited eating, and how taste and health perceptions relate to food preference; and further, whether cognitive restraint and disinhibited eating are associated with food preference decision reaction time.

Methods

Five hundred and seventeen adults participated in the study. Dietary cognitive restraint and disinhibited eating were assessed using the shortened Three-Factor Eating Questionnaire (TFEQ-R18). Participants also completed a dietary decision-making task to examine their food-related decisions. Participants were presented with 50 food items and asked to rate them for health and for taste. Participants were then presented with a reference food item and comparison items one at a time and asked to indicate which of the two foods they would prefer to eat.

Results

Participants with higher levels of cognitive restraint were more sensitive to health perceptions whereas those with higher levels of disinhibited eating were more sensitive to taste perceptions when indicating food preference. Reaction time analysis corroborated these results. Being classified as high for cognitive restraint was associated with faster reaction times if the preferred food was rated as healthier than the referent food. Conversely, being classified as high for disinhibited eating was associated with faster reaction times if the preferred food was rated as tastier than the referent food.

Conclusion

The dietary decision-making task appears to capture distinct aspects of dietary restraint and disinhibition and may be useful in future studies to measure and/or alter levels of dietary restraint and disinhibition.

The Metabolic Concept of Meal Sequence vs. Satiety: Glycemic and Oxidative Responses with Reference to Inflammation Risk, Protective Principles and Mediterranean Diet

With increasing exposure to eating opportunities and postprandial conditions becoming dominant states, acute effects of meals are garnering interest. In this narrative review, meal components, combinations and course sequence were questioned vis-à-vis resultant postprandial responses, including satiety, glycemic, oxidative and inflammatory risks/outcomes vs. protective principles, with reference to the Mediterranean diet. Representative scientific literature was reviewed and explained, and corresponding recommendations discussed and illustrated. Starting meals with foods, courses and/or preloads high in innate/added/incorporated water and/or fibre, followed by protein-based courses, delaying carbohydrates and fatty foods and minimizing highly-processed/sweetened hedonic foods, would increase satiety-per-calorie vs. obesogenic passive overconsumption. Similarly, starting with high-water/fibre dishes, followed by high-protein foods, oils/fats, and delayed/reduced slowly-digested whole/complex carbohydrate sources, optionally closing with simpler carbohydrates/sugars, would reduce glycaemic response. Likewise, starting with foods high in innate/added/incorporated water/fibre/antioxidants, high monounsaturated fatty acid foods/oils, light proteins and whole/complex carbohydrate foods, with foods/oils low in n-6 polyunsaturated fatty acids (PUFA) and n-6:n-3 PUFA ratios, and minimal-to-no red meat and highly/ultra-processed foods/lipids, would reduce oxidative/inflammatory response. Pyramids illustrating representative meal sequences, from most-to-least protective foods, visually communicate similarities between axes, suggesting potential unification for optimal meal sequence, consistent with anti-inflammatory nutrition and Mediterranean diet/meal principles, warranting application and outcome evaluation.

Eating Behaviors in Healthy Young Adult Twin Pairs Discordant for Body Mass Index

We aimed to study the eating behavioral traits that associate with body mass index (BMI) among BMI-discordant twin pairs. This cross-sectional study examined self-reported eating behaviors in 134 healthy young adult twin pairs (57 monozygotic [MZ] and 77 same-sex dizygotic [DZ]), of whom 29 MZ and 46 DZ pairs were BMI discordant (BMI difference ≥ 3 kg/m2). In both MZ and DZ BMI-discordant pairs, the heavier co-twins reported being less capable of regulating their food intake optimally than their leaner co-twins, mainly due to ‘frequent overeating’. Furthermore, the heavier co-twins reported augmented ‘disinhibited eating’, ‘binge-eating scores’ and ‘body dissatisfaction’. The twins agreed more frequently that the heavier co-twins (rather than the leaner co-twins) ate more food in general, and more fatty food, in particular. No significant behavioral differences emerged in BMI-concordant twin pairs. Overeating — measured by ‘frequent overeating’, ‘disinhibited eating’ and ‘binge-eating score’ — was the main behavioral trait associated with higher BMI, independent of genotype and shared environment.

Nutritional strategies of British professional and amateur natural bodybuilders during competition preparation

BACKGROUND

To prepare for competition, bodybuilders employ strategies based around: energy restriction, resistance training, cardiovascular exercise, isometric "posing", and supplementation. Cohorts of professional (PRO) natural bodybuilders offer insights into how these strategies are implemented by elite competitors, and are undocumented in the scientific literature.

METHODS

Forty-seven competitors (33 male (8 PRO, 25 amateur (AMA), 14 female (5 PRO, 9 AMA) participated in the study. All PROs were eligible to compete with the Drug Free Athletes Coalition (DFAC), and all AMAs were recruited from the British Natural Bodybuilding Federation (BNBF). Competitors in these organisations are subject to a polygraph and are drug tested in accordance with the World Anti-Doping Agency. We report the results of a cross-sectional study of drug free bodybuilders competing at BNBF qualifying events, and the DFAC and World Natural Bodybuilding Federation finals. Participants completed a 34-item questionnaire assessing dietary intake at three time points (start, middle and end) of competition preparation. Participants recorded their food intake over a 24-h period in grams and/or portions. Dietary intakes of PRO and AMA competitors were then compared. Repeated measures ANOVA was used to test if nutrient intake changed over time, and for associations with division.

RESULTS

Male PROs reported significantly (p < 0.05) more bodybuilding experience than AMAs (PRO: 12.3 +/- 9.2, AMA: 2.4 +/- 1.4 yrs). Male PROs lost less body mass per week (PRO: 0.5 +/- 0.1, AMA: 0.7 +/- 0.2%, p < 0.05), and reported more weeks dieting (PRO: 28.1 +/- 8.1, AMA: 21.0 +/- 9.4 wks, P = 0.06). Significant differences (p < 0.05) of carbohydrate and energy were also recorded, as well as a difference (p = 0.03) in the estimated energy deficit (EED), between male PRO (2.0 +/- 5.5 kcal) and AMA (- 3.4 +/- 5.5 kcal) competitors.

CONCLUSIONS

Longer diets and slower weight loss utilized by PROs likely contributed towards a lower EED compared to the AMAs. Slower weight loss may constitute an effective strategy for maintaining energy availability and muscle mass during an energy deficit. These findings require corroboration, but will interest bodybuilders and coaches.

Relationship between Hedonic Hunger and Health Interest on Habit and Sodium Intake Patterns in Food Consumption

Many people are motivated to eat healthily but find it difficult to override established and less healthy habits. Habits, by their nature, are unconscious and cued by the environment, thus making them powerful determinants of behavior. This study examined how hedonic hunger and health interest are related to habit and whether sodium consumption is mediated by hedonic hunger, health interest, and habit. A total of 117 students of Universitas Brawijaya took part in the study. Data analysis were done using Partial Least Square (PLS) and a semi-quantitative food frequency questionnaire (SQ-FFQ). PLS was used to analyze the influence of the relationship between independent and dependent variables. SQ-FFQ was used to determine sodium intake in grams/day. The average sodium intake in this study was 2.47 grams/day. This analysis shows that hedonic hunger and health interest had a significant impact on health habits but not on sodium intake.

Brain structures associated with eating behaviors in normal-weight young females

Eating behaviors play an important role in individuals' development, and restrained eaters have a higher risk of obesity in the future. In the present study, we used the Three-Factor Eating Questionnaire to measure restrained eating, uncontrolled eating, and emotional eating in 158 young, normal-weight, Chinese women. We developed a multiple linear regression model to identify significant structural brain changes associated with the above-mentioned eating behaviors. Uncontrolled eating scores were positively associated with the gray matter volume (GMV) of the cerebellum, and negatively associated with the GMV on the left side of the anterior cingulate cortex, middle cingulate cortex, and supplementary motor areas, indicating that uncontrolled eating behaviors not only are less inhibitory but also appear to be associated with the low-level processing of appetite. Increased GMV on the right side of the precuneus was associated with a higher level of restrained eating, which might be thus related to a lower sensitivity to behavioral inhibition in young females who follow a diet. In addition, we did not find a relationship between emotional eating behavior and GMV. Our findings show that eating-behavior-related structural brain changes may lead to a decrease in inhibition and an increase in food sensitivity.

Effects of Palatable Food Versus Thin Figure Conflicts on Responses of Young Dieting Women

Many young women use dieting to achieve a thinner figure yet most tend to fail as a result of heightened responsiveness to palatable food environments and increases in hedonic cravings. In this preliminary study, we developed a novel palatable food vs. thin figure conflict task to assess conflicting motives associated with eating among young women. Forty young dieting women [mean body mass index (BMI) = 22.98 kg/m², SD = 3.81] completed a food vs. figure conflict task within a 2 (distractor image: food vs. figure) × 2 (word-image congruence: congruent vs. incongruent) within-subjects design. Results supported the view that this new task could effectively capture conflict costs. Dieting young women displayed stronger food conflicts than figure conflicts based on having longer response delays and higher error rates in the food conflict condition than the figure conflict condition. Although young women often proclaimed "dieting" to achieve or maintain a good figure, dieters appeared to exhibit stronger preferences for palatable food cues relative to thin figure cues. These results provide important information for understanding automatic processing biases toward palatable foods and underscore the need for research extensions in other cultural contexts to determine whether such biases are universal in nature.

The Effects of Positive Affect and Episodic Future Thinking on Temporal Discounting and Healthy Food Demand and Choice Among Overweight and Obese Individuals: Protocol for a Pilot 2×2 Factorial Randomized Controlled Study

BACKGROUND

Unhealthy behaviors (eg, poor food choices) contribute to obesity and numerous negative health outcomes, including multiple types of cancer and cardiovascular and metabolic diseases. To promote healthy food choice, diet interventions should build on the dual-system model to target the regulation and reward mechanisms that guide eating behavior. Episodic future thinking (EFT) has been shown to strengthen regulation mechanisms by reducing unhealthy food choice and temporal discounting (TD), a process of placing greater value on smaller immediate rewards over larger future rewards. However, these interventions do not target the reward mechanisms that could support healthy eating and strengthen the impact of EFT-anchored programs. Increasing positive affect (PosA) related to healthy food choices may target reward mechanisms by enhancing the rewarding effects of healthy eating. An intervention that increases self-regulation regarding unhealthy foods and the reward value of healthy foods will likely have a greater impact on eating behavior compared with interventions focused on either process alone.

OBJECTIVE

This study aimed to introduce a protocol that tests the independent and interactive effects of EFT and PosA on TD, food choice, and food demand in overweight and obese adults.

METHODS

This protocol describes a factorial, randomized, controlled pilot study that employs a 2 (affective imagery: positive, neutral) by 2 (EFT: yes, no) design in which participants are randomized to 1 of 4 guided imagery intervention arms. In total, 156 eligible participants will complete 2 lab visits separated by 5 days. At visit 1, participants complete surveys; listen to the audio guided imagery intervention; and complete TD, food demand, and food choice tasks. At visit 2, participants complete TD, food demand, and food choice tasks and surveys. Participants complete a daily food frequency questionnaire between visits 1 and 2. Analyses will compare primary outcome measures at baseline, postintervention, and at follow-up across treatment arms.

RESULTS

Funding notification was received on April 27, 2017, and the protocol was approved by the institutional review board on October 6, 2017. Feasibility testing of the protocol was conducted from February 21, 2018, to April 18, 2018, among the first 32 participants. As no major protocol changes were required at the end of the feasibility phase, these 32 participants were included in the target sample of 156 participants. Recruitment, therefore, continued immediately after the feasibility phase. When this manuscript was submitted, 84 participants had completed the protocol.

CONCLUSIONS

Our research goal is to develop novel, theory-based interventions to promote and improve healthy decision-making and behaviors. The findings will advance decision-making research and have the potential to generate new neuroscience and psychological research to further understand these mechanisms and their interactions.

TRIAL REGISTRATION

ISRCTN Registry ISRCTN11704675; http://www.isrctn.com/ISRCTN11704675 (Archived by WebCite at http://www.webcitation.org/760ouOoKG).

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/12265.

Validation of the German Version of the Power of Food Scale in a General Population Sample

OBJECTIVE

The Power of Food Scale (PFS) is a self-report instrument for assessing appetitive motivation in the absence of caloric needs. The study aim was to validate the German PFS version in a large population sample.

METHODS

Complete information on all PFS items was available from 2,421 respondents (age ≥14) of a nationally representative sample of the German population. We examined the psychometric properties of the German PFS version and provided population-based normative data.

RESULTS

The 3-factor structure of the original scale was replicated in confirmatory factor analysis. The German PFS version demonstrated good internal consistency (α = 0.92 for the total scale). It was well accepted by the respondents, as indicated by a low proportion of missing item values (≤0.56%). While no significant differences were observed in the PFS mean scores between men and women, the scores increased across BMI categories. PFS was positively correlated with a measure of global eating disorder psychopathology (Eating Disorder Examination-Questionnaire 8) and the ultra-brief Patient Health Questionnaire for depression and anxiety.

CONCLUSIONS

Our findings suggest that the German PFS version has adequate psychometric properties and good reliability for measuring hedonic hunger in the general population. The provided population-based norms can be used for individual assessment.

Features and Trajectories of Eating Behavior in Weight-Loss Maintenance: Results from the German Weight Control Registry

OBJECTIVE

Eating behaviors such as dietary restraint and disinhibition caused by emotional and external cues play a relevant role in weight-loss maintenance.

METHODS

Four hundred forty individuals with successful weight-loss maintenance included in the prospective German Weight Control Registry completed the Dutch Eating Behavior Questionnaire. Participants were categorized into the following two weight groups: stable weight trajectory (WS) (n = 280) and unstable weight trajectory (WUS) (n = 160) over the 2-year assessment period.

RESULTS

Those with successful weight-loss maintenance had significantly higher scores on the restrained and emotional eating subscales compared with a general population (GP) sample. At baseline, the WS individuals had lower restrained, emotional, and external eating scores compared with the WUS individuals. Over the 2-year follow-up period, the trajectories of the restraint scores decreased in both groups but stayed elevated compared with the GP sample. Scores of the emotional and external eating subscales remained stable in the WS group but increased in the WUS group.

CONCLUSIONS

A certain degree of restraint seems to be necessary for successful weight-loss maintenance; however, high emotional and external eating may counteract this effect, resulting in weight regain in the long run.

What does self-reported "dieting" mean? Evidence from a daily diary study of behavior

Dieting is often recommended as a means of weight loss, yet research consistently shows that self-reported dieting does not result in weight loss. Toward resolving this discrepancy, this study assessed the daily dietary intake and weight control strategies of people who self-identified as dieting. College women (N = 266) provided a report of their eating pattern (dieting, "watching what I eat," and/or "eating healthy") followed by three daily diaries (24-hour recalls of dietary intake and weight control strategies) elicited on randomly selected days during a one-month period. Dieters were expected to report fewer daily calories, more daily exercise, and more daily weight control strategies than non-dieters. At baseline, 122 participants (45.9%) endorsed both "watching" and "eating healthy" ("Concerned Eaters") while 55 (20.7%) endorsed current dieting along with "watching" and "eating healthy" ("Dieters"). Just 3 (1.1%) endorsed dieting only, and 31 (11.7%) endorsed no eating pattern ("Unconcerned Eaters"). Dieters' mean BMI was in the overweight range; the mean BMIs of other groups were in the normal weight range. Dieters did not consistently endorse dieting across diaries. Nevertheless, Dieters reported fewer daily calories, and more overall weight control strategies, including more healthy weight control strategies, than Concerned Eaters. Across groups, participants' weights did not change significantly during the study. Dieters appear to engage in weight control strategies which could result in weight loss; however, their reports of whether they are dieting vary across days, suggesting a need for more consistent behavior. These results have clinical and research implications in the area of weight loss.

Conceptualizing body dissatisfaction in eating disorders within a self-discrepancy framework: a review of evidence

Body dissatisfaction, the negative subjective evaluation of one's body, is associated with many negative psychological and physical health consequences. One conceptualization of body dissatisfaction includes an experience of discrepancy between perceived actual and ideal body shapes. This paper reviews the literature on three facets of body dissatisfaction from the framework of self-discrepancy theory: perceptions of current weight, ideal body weight, and the relative importance of conforming to ideals. We review components of body dissatisfaction among healthy individuals and eating-disordered individuals. We also address the conceptualization's relationship among body dissatisfaction, weight history, and dieting to expand the impact of body dissatisfaction research and to provide more information on the nature and treatment of eating disorders.

A Low Energy-Dense Diet in the Context of a Weight-Management Program Affects Appetite Control in Overweight and Obese Women

Background

Low energy-dense (LED) foods reduce energy intake (EI); whether this effect is sustained over time and during weight loss is unknown.

Objective

This trial examined the effects of LED compared with high energy-dense (HED) meals on appetite, EI, and control over eating in the laboratory and during a weight-management program that encourages unrestricted intake of LED foods [Slimming World, UK (SW)] compared with a self-led Standard Care program [NHS weight-loss plan (SC)].

Methods

Overweight and obese women [n = 96; mean ± SD age: 41.03 ± 12.61 y; mean ± SD body mass index (in kg/m2): 34.00 ± 3.61] were recruited from the SW or SC programs. Primary outcomes included appetite, food preferences (liking and wanting for LED and HED foods), cravings, and evening meal EI (LED, HED) in response to calorie-matched LED (≤0.8 kcal/g) and HED (≥2.5 kcal/g) breakfast and lunch meals. Probe-day tests were conducted at weeks 3 and 4 and repeated at weeks 12 and 13 in a within-day crossover design. Secondary outcomes, including body weight and program experience, were measured from weeks 1 to 14 in a parallel-group design. Dietary compliance was monitored with the use of weighed food diaries at weeks 3 and 12.

Results

Intention-to-treat (ITT) and completers analyses showed that the SW group lost more weight than the SC group [ITT: -5.9% (95% CI: -4.7%, -7.2%) compared with -3.5% (-2.3%, -4.8%), P < 0.05; completers: -6.2% (-4.8%, -7.6%) compared with 3.9% (-2.5%, -5.2%), P < 0.05]. The SW group reported greater control over eating and more motivation to continue the program compared with the SC group. LED meals increased sensations of fullness and reduced hunger on probe days (P < 0.001). Total-day EI was 1057 ± 73 kcal less (95% CI: 912, 1203 kcal; 36%) under LED compared with HED conditions (P < .001). Liking for LED and HED foods and wanting for HED foods were lower before lunch under LED compared with HED conditions, and liking decreased to a greater extent after the LED lunch. The SW group reported fewer cravings under LED compared with HED conditions (P < 0.05). On probe days, appetite and EI outcomes did not differ between weeks 3 and 12 or between the SW and SC groups.

Conclusion

LED meals improve appetite control in women attempting weight loss and the effect is sustainable. Consumption of LED meals likely contributed to weight loss in the SW program. This study was registered at clinicaltrials.gov as NCT02012426.

Testing a mobile mindful eating intervention targeting craving-related eating: feasibility and proof of concept

Theoretically driven smartphone-delivered behavioral interventions that target mechanisms underlying eating behavior are lacking. In this study, we administered a 28-day self-paced smartphone-delivered intervention rooted in an operant conditioning theoretical framework that targets craving-related eating using mindful eating practices. At pre-intervention and 1-month post-intervention, we assessed food cravings among adult overweight or obese women (N = 104; M age = 46.2 ± 14.1 years; M BMI = 31.5 ± 4.5) using ecological momentary assessment via text message (SMS), self-reported eating behavior (e.g., trait food craving), and in-person weight. Seventy-eight participants (75.0%) completed the intervention within 7 months ('all completers'), and of these, 64 completed the intervention within 3 months ('timely completers'). Participants experienced significant reductions in craving-related eating (40.21% reduction; p < .001) and self-reported overeating behavior (trait food craving, p < .001; other measures ps < .01). Reductions in trait food craving were significantly correlated with weight loss for timely completers (r = .30, p = .020), this pattern of results was also evident in all completers (r = .22, p = .065). Taken together, results suggest that smartphone-delivered mindful eating training targeting craving-related eating may (1) target behavior that impacts a relative metabolic pathway, and (2) represent a low-burden and highly disseminable method to reduce problematic overeating among overweight individuals. ClinicalTrials.gov registration: NCT02694731.

Mediation and modification of genetic susceptibility to obesity by eating behaviors

Background: Many genetic variants show highly robust associations with body mass index (BMI). However, the mechanisms through which genetic susceptibility to obesity operates are not well understood. Potentially modifiable mechanisms, including eating behaviors, are of particular interest to public health.Objective: Here we explore whether eating behaviors mediate or modify genetic susceptibility to obesity.Design: Genetic risk scores for BMI (BMI-GRSs) were calculated for 3515 and 2154 adults in the Fenland and EDEN (Etude des déterminants pré et postnatals de la santé et du développement de l'enfant) population-based cohort studies, respectively. The eating behaviors-emotional eating, uncontrolled eating, and cognitive restraint-were measured through the use of a validated questionnaire. The mediating effect of each eating behavior on the association between the BMI-GRS and measured BMI was assessed by using the Sobel test. In addition, we tested for interactions between each eating behavior and the BMI-GRS on BMI.Results: The association between the BMI-GRS and BMI was mediated by both emotional eating (EDEN: P-Sobel = 0.01; Fenland: P-Sobel = 0.02) and uncontrolled eating (EDEN: P-Sobel = 0.04; Fenland: P-Sobel = 0.0006) in both sexes combined. Cognitive restraint did not mediate this association (P-Sobel > 0.10), except among EDEN women (P-Sobel = 0.0009). Cognitive restraint modified the relation between the BMI-GRS and BMI among men (EDEN: P-interaction = 0.0001; Fenland: P-interaction = 0.04) and Fenland women (P-interaction = 0.0004). By tertiles of cognitive restraint, the association between the BMI-GRS and BMI was strongest in the lowest tertile of cognitive restraint, and weakest in the highest tertile.Conclusions: Genetic susceptibility to obesity was partially mediated by the "appetitive" eating behavior traits (uncontrolled and emotional eating) and, in 3 of the 4 population groups studied, was modified by cognitive restraint. High levels of cognitive control over eating appear to attenuate the genetic susceptibility to obesity. Future research into interventions designed to support restraint may help to protect genetically susceptible individuals from weight gain.

Effects of Chocolate Deprivation on Implicit and Explicit Evaluation of Chocolate in High and Low Trait Chocolate Cravers

Diet failures are often attributed to an increase in cravings for attractive foods. However, accumulating evidence shows that food cravings actually decrease during energy-restricting weight-loss interventions. The current study aimed at elucidating possible mechanisms that may explain how and under which circumstances food cravings in- or decrease during dieting. Specifically, decreases in food cravings during weight-loss diets may be due to effects of energy restriction (homeostatic changes) and to effects of avoiding specific foods (hedonic changes). Thus, we used a selective, hedonic deprivation (i.e., restricting intake of a specific food in the absence of an energy deficit) that precludes homeostatic changes due to energy restriction. Furthermore, interindividual differences in food craving experiences might affect why some individuals are more prone to experience cravings during dieting than others. Thus, we investigated whether a selective deprivation of chocolate would in- or decrease craving and implicit preference for chocolate as a function of trait-level differences in chocolate craving. Participants with high and low trait chocolate craving (HC, LC) refrained from consuming chocolate for 2 weeks but otherwise maintained their usual food intake. Both groups underwent laboratory assessments before and after deprivation, each including explicit (i.e., state chocolate craving) and implicit measures (i.e., Single Category Implicit Association Test, SC-IAT; Affect Misattribution Procedure, AMP). Results showed that hedonic deprivation increased state chocolate craving in HCs only. HCs also showed more positive implicit attitudes toward chocolate than LCs on the SC-IAT and the AMP irrespective of deprivation. Results help to disambiguate previous studies on the effects of dieting on food cravings. Specifically, while previous studies showed that energy-restricting diets appear to decrease food cravings, the current study showed that a selective, hedonic deprivation in the absence of an energy deficit increases food cravings. However, this effect can only be observed for individuals with high trait craving levels. Thus, if attractive foods are strictly avoided through a selective deprivation, HCs are at risk to experience craving bouts in the absence of an energy deficit. As implicit preference was unaffected by chocolate deprivation, strong implicit preference for chocolate likely characterize a stable mechanism that drives consumption in HCs.