Nonregulation of food intake in restrained, emotional, and external eaters

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.

See the cake and have it too? Investigating the effect of watching a TV cooking show on unhealthy food choices

This study tested whether exposure to food-related (vs. non-food related) TV content would increase unhealthy food choices in unsuccessful restrained eaters (i.e., chronic dieters with low perceived self-regulatory success; PSRS), decrease unhealthy food choices in successful restrained eaters (i.e., chronic dieters with high PSRS), and would not affect food choices in unrestrained eaters (i.e., non-dieters). As such, we attempted to (1) explain previous mixed findings on behavioral effects of exposure to food-related TV content, and (2) generalize previous findings on successful and unsuccessful restrained and unrestrained eaters' differential reactivity to isolated food cues (e.g., food words) to food cues embedded in TV content. In a one-factorial between-subjects experiment, participants viewed a cooking segment in which high-calorie cakes were prepared (n = 50) or a non-food segment (n = 62) of a TV show. The percentage of unhealthy (vs. healthy) food choices in a computerized choice task served as dependent variable. Eating restraint and PSRS were measured afterwards. In contrast to the hypothesis, no three-way interaction between TV content, eating restraint, and PSRS on the percentage of unhealthy food choices was found. However, it was found that overall, people with lower levels of PSRS made a higher percentage of unhealthy food choices compared to people with higher levels of PSRS. Contrasting findings from previous research using isolated food cues, this study showed no evidence of unsuccessful restrained eaters' heightened susceptibility to food cues in TV content, possibly explained by a lower salience of or attention to food cues.

More restriction, more overeating: conflict monitoring ability is impaired by food-thought suppression among restrained eaters

Numerous studies have shown that restrained eating is not an effective weight loss strategy. Restrained eaters often suppress their desires and thoughts about tasty food, which makes it more difficult to control themselves in subsequent eating behavior. The ego depletion impairs conflict monitoring abilities. Therefore, this study explored the effects of food thoughts suppression on restrained eaters' conflict monitoring. Therefore, this study used functional magnetic resonance imaging (fMRI) methods to explore changes in the activity of brain regions involved in conflict monitoring when restrained eaters choose between high- and low-calorie foods after either suppressing or not suppressing thoughts about food. The results showed that, compared to the control condition, after suppression of such thoughts, restrained eaters chose more high-calorie foods and displayed decreased activity in the dorsal anterior cingulate cortex-an important region in charge of conflict monitoring. At the same time, the functional coupling of the dorsal anterior cingulate cortex and the precuneus increased. Our findings suggest that restrained eaters' suppression of thoughts about tasty food could lead to a decline in their ability to monitor conflicts between current behaviors and goals, which in turn leads to unhealthy eating behavior.

Effect of dietary restraint and mood state on attentional processing of food cues

BACKGROUND AND OBJECTIVES

Research linking dietary restraint to attentional bias toward food cues has been equivocal, suggesting that dietary restraint may only influence attentional processing of food in certain contexts. The present study examined whether negative mood strengthens the association between dietary restraint and attention bias for food.

METHODS

Healthy female participants were randomized to either a neutral (n = 47) or negative mood (n = 49) induction. Participants then completed a visual search task featuring targets displayed adjacent to pictures of palatable food, musical instruments, or non-instrument filler objects. Attention bias for food was operationalized as shorter response latency when the target appeared adjacent to palatable food as compared to musical instruments. Attention bias was examined in a 2 (mood condition) × 2 (picture: food vs. instrument) × 2 (target location: match vs. mismatch) repeated measures ANCOVA, with dietary restraint as a continuous covariate and response latency as the dependent variable.

RESULTS

Though there was no evidence of an interaction between mood condition and dietary restraint, mood had an influence on attention allocation. Contrary to study hypotheses, individuals in the neutral mood condition, but not those in the negative mood condition, responded in a manner indicative of bias toward food.

LIMITATIONS

Additional research is necessary to validate the experimental task used in the present study to assess food-specific attentional bias.

CONCLUSIONS

Neutral mood may be associated with enhanced processing of palatable food cues. Critically, results do not support the hypothesized link between negative mood and attention bias for food.

Acute versus repeated chocolate exposure: Effects on intake and cravings in restrained and unrestrained eaters

The cue-reactivity model, which is based on conditioning processes, posits that repeated food exposure (in the absence of consumption) should decrease cue reactivity. To examine whether repeated chocolate exposure attenuates cravings and intake, relative to those exposed to an acute cue, a 2 (repeated vs acute cue) × 2 (restrained vs unrestrained eaters) design was employed. Fifty female participants were recruited. Repeated exposure reduced cravings in unrestrained eaters (relative to acute exposure), but increased cravings in restrained eaters. An interaction between restraint and exposure emerged on intake, such that restrained eaters ate less after acute exposure than did unrestrained eaters.

Inspiration or deflation? Feeling similar or dissimilar to slim and plus-size models affects self-evaluation of restrained eaters

The present studies examined the effect of perceiving images of slim and plus-size models on restrained eaters' self-evaluation. While previous research has found that such images can lead to either inspiration or deflation, we argue that these inconsistencies can be explained by differences in perceived similarity with the presented model. The results of two studies (ns=52 and 99) confirmed this and revealed that restrained eaters with high (low) perceived similarity to the model showed more positive (negative) self-evaluations when they viewed a slim model, compared to a plus-size model. In addition, Study 2 showed that inducing in participants a similarities mindset led to more positive self-evaluations after viewing a slim compared to a plus-size model, but only among restrained eaters with a relatively high BMI. These results are discussed in the context of research on social comparison processes and with regard to interventions for protection against the possible detrimental effects of media images.

Mere exposure to palatable food cues reduces restrained eaters' physical effort to obtain healthy food

We examined whether exposure to cues of attractive food reduces effortful behavior toward healthy foods for restrained eaters. After manipulating food pre-exposure, we recorded handgrip force while presenting participants with pictures of healthy food objects. Because participants were led to expect that they could obtain each object (not specified beforehand) by squeezing the handgrip as forcefully as possible while the object was displayed on the screen, the recorded handgrip force constitutes a measure of spontaneous effortful behavior. Results show that restrained eaters, but not unrestrained eaters, displayed less forceful action toward healthy food objects (i.e., lower exertion of force) when pre-exposed to tempting food cues. No effects were found on palatability perceptions of the healthy foods. The results provide further insight into why restrained eaters have difficulties in maintaining a low-calorie diet in food-rich environments.

Negative mood increases selective attention to food cues and subjective appetite

Following negative reinforcement and affect-regulation models of dysfunctional appetitive motivation, this study examined the effect of negative mood on objective and subjective cognitive indices of motivation for food; i.e., attentional bias for food cues and self-reported hunger/urge to eat, respectively. The study extended previous research on the effect of mood on food motivation by using (i) an experimental mood manipulation, (ii) an established index of attentional bias from the visual-probe task and (iii) pictorial food cues, which have greater ecological validity than word stimuli. Young female adults (n=80) were randomly allocated to a neutral or negative mood induction procedure. Attentional biases were assessed at two cue exposure durations (500 and 2000ms). Results showed that negative mood increased both attentional bias for food cues and subjective appetite. Attentional bias and subjective appetite were positively inter-correlated, suggesting a common mechanism, i.e. activation of the food-reward system. Attentional bias was also associated with trait eating style, such as external and restrained eating. Thus, current mood and trait eating style each influenced motivation for food (as reflected by subjective appetite and attentional bias). Findings relate to models of cognitive mechanisms underlying normal and dysfunctional appetitive motivation and eating behaviour.

Does Cognitive Distraction Lead to Overeating in Restrained Eaters?

Restrained eaters have been found to overeat after various events or so-called disinhibitors, such as eating a preload or strong emotional states. Little research has focused on why such events lead to a break of the restrained eaters' control and to overeating. The present study examines the role of cognitive distraction as a possible mechanism underlying these effects. Two experiments were conducted, both designed to test hypotheses derived from Wegner's Ironic Process Theory and focusing on the behavioural consequences of cognitive control over eating. In both experiments subjects were tested in a 2 (restrained/unrestrained) by 2 (distraction/no distraction) design. The results do not confirm the prediction flowing from the Ironic Process Theory: cognitive distraction does not lead to overeating in restrained eaters. Implications of these findings for the Boundary Model are also discussed.

Effects of exercise and restrained eating behaviour on appetite control

Obesity is a global epidemic; increased consumption of energy-dense food and reduced physical activity levels are likely to be the main drivers. Previous cross-sectional research has shown that sedentary males, unlike their active counterparts, are unable to compensate for previous energy intake (EI). Using a longitudinal design a 6-week exercise intervention was found to improve short-term appetite control, leading to a more ‘sensitive’ eating behaviour in response to previous EI, both acutely at a test meal and for the next 24 h. Although the mechanisms whereby acute and chronic exercise improves short-term appetite remain unknown, post-ingestive satiety peptides are likely to be involved. Acute exercise was found to increase postprandial levels of polypeptide YY, glucagon-like peptide-1 and pancreatic polypeptide but to have no impact on ghrelin, suggesting that exercise can trigger physiological changes in satiety hormone secretion that could help in appetite control and weight maintenance. In the context of an increased availability of highly-palatable food, dietary restraint may be increasingly important. Although restraint has been associated with abnormal eating behaviour, in the laboratory no counter-regulation was found in restrained eaters when presented with a buffet meal 60 min after a high-energy preload or when a pasta-meal was presented 3 h after preloading. Although restraint was not found to impact on polypeptide YY or TAG, lower postprandial glucose and insulin plasma levels were observed in restrained eaters, together with increased feelings of fullness. In conclusion, short-term appetite control seems to be favourably modified by exercise, while the impact of restraint on appetite seems to be more complex.

Measurement of dietary restraint: validity tests of four questionnaires

This study tested the validity of four measures of dietary restraint: Dutch Eating Behavior Questionnaire, Eating Inventory (EI), Revised Restraint Scale (RS), and the Current Dieting Questionnaire. Dietary restraint has been implicated as a determinant of overeating and binge eating. Conflicting findings have been attributed to different methods for measuring dietary restraint. The validity of four self-report measures of dietary restraint and dieting behavior was tested using: (1) factor analysis, (2) changes in dietary restraint in a randomized controlled trial of different methods to achieve calorie restriction, and (3) correlation of changes in dietary restraint with an objective measure of energy balance, calculated from the changes in fat mass and fat-free mass over a six-month dietary intervention. Scores from all four questionnaires, measured at baseline, formed a dietary restraint factor, but the RS also loaded on a binge eating factor. Based on change scores, the EI Restraint Scale was the only measure that correlated significantly with energy balance expressed as a percentage of energy required for weight maintenance. These findings suggest that, of the four questionnaires tested, the EI Restraint Scale was the most valid measure of the intent to diet and actual caloric restriction.

Construct validation of the Restraint Scale in normal-weight and overweight females

The Restraint Scale (RS) is a widely used measure to assess restrained eating. The purpose of this study was to examine the construct validity of the RS in a sample of normal-weight (n=349) and overweight (n=409) females using confirmatory factor analyses of the RS in relation to other measures for dieting, overeating and body dissatisfaction. Following Laessle et al. [(1989a). A comparison of the validity of three scales for the assessment of dietary restraint. Journal of Abnormal Psychology, 98, 504-507], we assumed a three-factor structure: (1) overeating and disinhibitory eating, (2) dieting and restriction of food intake, and (3) body dissatisfaction and drive for thinness. Analyses revealed that the RS loaded significantly on all three factors for both samples, confirming its multifactorial structure. However, the RS appears to capture these constructs differently in overweight and normal-weight females such that the RS may overestimate restraint in overweight individuals. This may explain the greater effectiveness of the RS in predicting counter-regulation in normal-weight than in overweight samples of dieters.

The Stice model of overeating: Tests in clinical and non-clinical samples

The present study tested the dual pathway model of Stice [. A review of the evidence for a sociocultural model of bulimia nervosa and an exploration of the mechanisms of action. Clinical Psychology Review, 14, 633-661 and . A prospective test of the dual-pathway model of bulimic pathology: mediating effects of dieting and negative affect. Journal of Abnormal Psychology, 110, 124-135.] in a non-clinical sample of female adolescents and a clinical sample of female eating disorder patients. The model assumes that negative affect and restrained eating mediates the link between body dissatisfaction and overeating. We also tested an extended version of the model postulating that negative affect and overeating are not directly related, but indirectly through lack of interoceptive awareness and emotional eating. Structural equation modelling was used to test our models. First, in the two samples, body dissatisfaction and drive for thinness were associated with overeating/binge eating. In both clinical and adolescent sample, we found support for the negative affect pathway and not for the restraint pathway. Lack of interoceptive awareness and emotional eating appear to (partly) explain the association between negative affect and overeating. Emotional eating was much more strongly associated with overeating in the clinical than in the adolescent sample. In sum, we found substantial evidence for the negative affect pathway in the dual pathway model. The link between body dissatisfaction and overeating in this respect might be explained by the fact that negative affect, due to body dissatisfaction, is related to a lack of awareness of personal feelings and to eating when dealing with negative emotions, which on its turn is associated with overeating.

Absence of a disinhibition effect of alcohol on food consumption

Alcohol is frequently mentioned as a disinhibitor of restrained eating behavior although only a small number of studies have investigated this disinhibition effect. The present study was conducted to fill this gap. A total of 116 female college students participated in a questionnaire-based assessment and a taste-test experiment. Before the taste test, half of the participants consumed a preset amount of alcohol-laced orange juice, the other half were given plain orange juice. The dependent variable was the amount of savory crackers eaten during the taste test. The Dutch Eating Behavior Questionnaire (DEBQ), the Three-Factor Eating Questionnaire (TFEQ), and the Restraint Scale (RS) were used to measure eating behavior dimensions, which formed the independent variables in various regression analyses. No disinhibition effect was found. On the contrary, participants scoring high on restraint (DEBQ, TFEQ) proved to consume even less food than those having lower scores. Participants that rated high on the scales measuring tendency toward overeating consumed more food than participants with low scores. These results support earlier contentions that the validity of the Restraint Theory's statement that dieting leads to overeating is questionable.

Tendency toward overeating and restraint as predictors of food consumption

Restrained eaters have repeatedly been found to overeat following a preload, which phenomenon is called the disinhibition effect. Remarkably, the disinhibition effect is only found when the restraint scale (RS) is used, and never when other measures of restraint, like the three-factor eating questionnaire (TFEQ) or the Dutch eating behavior questionnaire (DEBQ) are applied. Recent research has shown that tendency toward overeating appears to be a better predictor of food consumption than dietary restraint. The present study examines the predictive value of preload, tendency toward overeating and dietary restraint. An experiment was carried out with 209 female participants with the aim to evaluate whether the results of the study [Int J Eating Disorders 28 (2000) 333] are robust. In addition to the RS, the TFEQ and DEBQ were used to measure restraint and tendency toward overeating. Again, no disinhibition effect occurred, confirming the results of the previous study. Restraint, as measured by the three questionnaires, was not related to food consumption. In contrast, tendency toward overeating was significantly related to food consumption. Restraint theory's contentions that dieting leads to overeating might be valid for only some dieters, namely those with a high tendency toward overeating.

Ice-cream consumption, tendency toward overeating, and personality

OBJECTIVE

The exploration of the mechanisms underlying the tendency toward overeating by investigating the Dutch Eating Behavior Questionnaire (DEBQ)/Revised Eating Disorders Inventory (EDI-R) disinhibition, in sequence to the milkshake-ice cream study (van Strien, Cleven, and Schippers, in press).

METHOD

In hierarchical multiple regression analyses, the relative predictive power for ice-cream consumption was assessed, that is, emotional versus external versus bulimic eating using scales of the DEBQ and the EDI-R. In nonplanned stepwise multiple regression analyses, the association was assessed between these three types of eating behaviors and non-eating-related EDI-R scales.

RESULTS

Emotional eating was the most important variable for ice-cream consumption. External eating was borderline significant and bulimic eating nonsignificant when emotional and external eating had been partialled out. Emotional eating was best predicted by the EDI-R scales Asceticism, Interoceptive Awareness, and Social Insecurity.

DISCUSSION

Results are consistent with psychosomatic theory, which focuses on emotional eating as the result of confusion and apprehension in recognizing and accurately responding to emotional and visceral states related to hunger and satiety.

Dietary restraint, attributional styles for eating, and preloading effects

A total of 319 undergraduates completed the Restraint Scale and an Eating Attributional Style Questionnaire (EASQ). Subsequently, 101 female students participated in the classic preloading experiment. The results indicated that restrained eating was associated with an external locus of control attribution style, particularly for indulgent food consumption (ELCifc). Partial preloading effects for Restraint were found: The amount consumed increased as a function of Restraint in the preload condition. A more complete pattern of preloading was found for the ELCifc attribution style. In addition, the relationship between Restraint and food consumed in the preload condition was no longer significant with the ELCifc attribution style partialled out. The findings supported the hypotheses that: (a) restrained eaters display an external attribution style of learned helplessness and (b) related cognitions serve as a cause of preloading effects.

Success and failure in the measurement of restraint: notes and data

OBJECTIVE

The clarification of the present confusion about the confounding of success and failure in the measurement of restrained eating.

METHOD

Close inspection of results regarding the Restraint Scale (RS) and the restraint scales of homogeneous measures of restrained eating, for example, the restraint scales of the Three-Factor Eating Questionnaire (TFEQ) and the Dutch Eating Behaviour Questionnaire (DEBQ).

RESULTS

Various studies have led to the distinction of two different types of confounding of success and failure in the measurement of restrained eating. The first confounding is associated with the RS and the inability of its scores to differentiate between inhibition and disinhibition of restraint in one person, as a result of variance across time within one person in food intake and binging. The second type of confounding applies to the homogeneous measures of restrained eating, for example, the restraint scales of the TFEQ and DEBQ. Here the confounding is associated with the inability of their restraint scores to differentiate between dieters with low versus high susceptibility toward failure of restraint, as a result of variance across persons in food intake and binging.

DISCUSSION

In contrast to the first confounding, the confounding of successful and unsuccessful dieters in subjects with high restraint scores can be easily unconfounded, by using a two-factorial classification including both scores on "pure" measures of restraint and scales for tendency toward overeating. For future research, the distinction between successful and unsuccessful dieters is an important first step in clarifying why some dieters do overeat under certain conditions.

The concurrent validity of a classification of dieters with low versus high susceptibility toward failure of restraint

It has been experimentally shown that the population of high restrained eaters consists of two subpopulations, i.e., those with a low and those with a high susceptibility toward failure of restraint. Only those who combined high restraint with high scores on the disinhibition scale of the TFEQ (Three-Factor Eating Questionnaire) showed overeating after a preload. The aim of the present study was to assess the concurrent validity of a two-factorial classification using the Dutch Eating Behavior Questionnaire (DEBQ) scales for restraint, emotional and external eating, as well as the bulimia scale of the Eating Disorder Inventory (EDI) for locating dieters with low or high susceptibility toward failure. It was examined whether the resulting two-group classification is associated with self-reported behaviors and features of psychopathology, which are generally thought to differentiate both groups of dieters. The results indicated that the two-group classification was indeed associated with many of these behaviors and features of psychopathology. It was concluded that this classification has a good concurrent validity.

Are Most Dieters Unsuccessful? An Alternative Interpretation of the Confounding of Success and Failure in the Measurement of Restraint

Since Ogden's 1993 study, the concept of restrained eating as measured by the restrained eating scale of the Dutch Eating Behaviour Questionnaire (DEBQ-R) has been further explored. In the present study, as in Ogden's study, most subjects did not differentiate between items relating to attempts at dieting and actual dieting. Ogden's conceptualization of the confounding of successful and failed restraint in the measurement of restraint, however, was not supported. First, there was no indication that trying to eat less is associated with unsuccessful dieting and actually eating less with successful dieting. Secondly, in contrast to Ogden, in our study the highest restraint score was found in subjects with low susceptibility toward failure of restraint. The results are discussed in terms of an alternative interpretation of the confounding of success and failure in the measurement of restraint. Instead of a confounding of success and failure within a subject (successful restraint is followed by failure of restraint), it would be better interpreted in terms of a difference in eating behaviour between subjects. Within the population of restraint eaters there are two subpopulations: those with a low versus those with a high tendency toward overeating - successful and failed dieters, respectively.

A problematic counter-regulation experiment: implications for the link between dietary restraint and overeating

The current study failed to find any evidence of laboratory counter-regulation amongst restrained eaters given a preload, regardless of the measures of dietary restraint used to classify subjects, including dieting status on the day of the study. Furthermore, there was no evidence to suggest that high restrainers characteristically overeat or experience a sense of loss of control over eating in naturalistic settings. These findings indicate that the link between dietary restraint and overeating or bulimic episodes is, at most, a weak one. Future investigations must incorporate more detailed and sensitive measures of both restraint and overeating if analogue studies are to be useful for understanding the process involved in clinically significant episodes of overeating or binge eating.

Eating style and eating behaviour in adolescents

The relationship between eating style, attitudes towards food and food intake was investigated in 846 British adolescent schoolchildren. Eating style was assessed with the Dutch Eating Behaviour Questionnaire, attitudes towards food with a series of specially prepared questions, and food intake with a diet history taken by a dietitian. The results showed that restraint, external and emotional eating were associated with very different profiles of attitudes and behaviour. Restrained subjects had a higher body weight, more negative attitudes towards food, a lower likelihood of overeating and a lower overall energy intake. External eaters had a lower body weight, positive attitudes to food, and reported a higher energy intake. Emotional eaters fell in between in some ways, with some signs of situational loss of control combined with a negative attitude towards overeating. While external eating appeared to be attenuated by restraint, emotional eating was enhanced by it. The implications of these eating styles for later patterns of eating and weight are discussed.

No counterregulation after breaking the external restraint of children

At the present, it is unknown how restraint and binge eating/counterregulation are exactly related. Earlier studies on this relationship suffer from two main shortcomings: the studies are all correlational in nature or could not rule out the contribution of confounding variables such as weight loss. The present study investigated whether a break of restraint is a sufficient condition for the occurrence of counterregulation by studying a restrained sample which is not liable to dieting practices and weight loss. The externally imposed restraint on children with regard to eating sweets was broken. However, after breaking their external restraint the children did not counterregulate. It is discussed whether restraint of food intake is really as important for binge eating as it is claimed to be or whether it is merely a consequence or an epiphenomenon of binge eating.

A case of bulimia successfully treated by cue exposure

In the present case-study, a 22-year-old female patient with a 7-year history of bulimia nervosa was treated by cue-exposure. During cue-exposure sessions the relationship between CS (stimuli associated with binge-eating behaviour) and UCS (the sensations related to the intake of binge food) was broken. As predicted, the patients' craving for food declined within as well as between cue exposure sessions and a radical decrease in the frequency of binge-eating persisted for at least nine months. Although during the therapy no explicit attention was paid to the patient's low mood and irrational self-talk, mood was improved and beliefs were less irrational after cue-exposure and at the follow-ups. The data suggest that cue exposure may be an effective part of the treatment of bulimia nervosa.

Restrained eaters are rapidly habituating sensation seekers

Several authors have pointed to similarities between eating disorders and addictive behaviors. In earlier studies, addicts were found to score high on the Sensation Seeking Scale (SSS) and to habituate rapidly to neutral stimuli. In this study, we found experimental support for an addiction model of eating disorders: restrained eaters also scored significantly higher on the Sensation Seeking Scale and also habituated significantly quicker to a series of neutral stimuli than unrestrained eaters. No clear evidence was found for the hypothesis that restrained eaters score lower on measurements of anxiety. It is hypothesized that rapid habituation promotes sensation seeking, which may be manifested in excessive consumption of either drugs or food. Restraint may be a strategy to prevent negative consequences of sensation seeking and excessive consumption. The model is related to earlier experimental findings.