Non-restrained Eaters Research Articles

“Neurotic people tend to eat less when disinhibited”: The mediating role of food-related cognitive flexibility in restrained eaters

ObjectivesThis study aims to reveal the individual differences in Neuroticism and cognitive flexibility among successful restrained eaters (SREs), unsuccessful restrained eaters (UREs), and non-restrained eaters (NREs). Moreover, this study is dedicated to investigating whether certain personality traits and cognitive flexibility could concurrently influence disinhibited eating behaviors among restrained eaters and reveal the pathways through which they interact. MethodsFemale participants aged 17 and 24 years (NREs = 23; SREs = 24; UREs = 23) were assessed with body mass index (BMI) and appetite state measurement, the Dutch Eating Behavior Questionnaire (DEBQ), the NEO Five-Factor Inventory (NEO-FFI), and the Positive and Negative Affect Schedule. To measure behavioral and neural responses related to cognitive flexibility, participants were required to complete a food-related switching task, and their brain activities were recorded through the technique of electroencephalography (EEG). Here we analyzed two widely investigated components—the N2 and P3 components that separately relate to conflict monitoring and response inhibition. ResultsThe behavioral performance of food-related task switching did not show significant between-group differences. However, in comparison to NREs and SREs, UREs elicited larger N2 and lower P3 amplitudes during task switching. In addition, UREs exhibited a lower level of Neuroticism than SREs and NREs. Furthermore, food-related task switching induced N2 amplitude fully mediated the association between Neuroticism and disinhibited eating behavior in restrained eaters controlled for BMI and negative affect. Importantly, when a parallel mediation model with N2 and P3 was built concurrently, N2 was still able to fully mediate the association. ConclusionAccording to behavioral and neural evidence, increased N2 amplitude induced by food-related task switching totally mediated the negative association between Neuroticism and disinhibited eating in restrained eaters.

Emulsion Colloidal Gastric Stability and Lipid Droplet Physical State Modulate Gastric Emptying and Short-Term Satiety in Healthy Men

Abstract Objectives The aim of this randomized crossover study was to investigate the influences of TAG droplet physical state at 37°C and emulsion gastric colloidal stability on gastric emptying (GE), postprandial lipemia and satiety in healthy men. It was hypothesized that emulsions susceptible to flocculation in the stomach would augment GE compared to acid stable emulsions, and that the acute lipemic and satiety responses would be attenuated for emulsions containing crystalline TAG and/or an acid unstable emulsifier. Methods Twenty % palm stearin or palm olein emulsions with similar particle size distributions where formulated using either Tween80 (acid stable emulsifier) or Span60 (acid unstable emulsifier). The four emulsions contained partially crystalline droplets that remained stable (SS) or destabilized (SU) or contained liquid droplets that remained stable (LS) or destabilized (LU) when exposed to simulated in vitro gastric conditions. Fifteen healthy adult male non-restrained eaters (mean ± SD age: 24.9 ± 4.5; BMI: 26.0 ± 2.0 kg/m2; fasting TAG: 0.9 ± 0.3 mmol/L) consumed 250 mL of one of the emulsions on four occasions separated by at least 6 days. Baseline fasting and 6-hr postprandial ultrasound gastric antrum measurements, satiety visual analogue scales (VAS), and blood samples for analysis of plasma TAG and hunger and satiety hormones were collected. Results Gastric antrum area decreased faster (P ≤ 0.01) for the acid unstable emulsions (SU and LU) indicating faster GE. Postprandial TAG response did not differ significantly between any of the emulsions, but there were differences in postprandial satiety responses. 3-hr incremental area under the curve (iAUC) was significantly lower for hunger (P = 0.021) and desire to eat (P = 0.031) ratings and 6-hr iAUC was significantly higher for ghrelin (P = 0.028) with LS compared to SU. Plasma PYY and GLP-1 change from baseline values were also higher following consumption of LS compared to LU (P = 0.028) (for PYY), and compared to SU (P = 0.008) and LU (P = 0.001) (for GLP-1). Conclusions Emulsion phase separation in the stomach was associated with delayed GE, which corresponded to enhanced satiety with the acid stable emulsion containing TAG in the liquid state. Funding Sources Canada's Natural Sciences and Engineering Research Council.

Effects of negative mood state on event-related potentials of restrained eating subgroups during an inhibitory control task

Negative mood states are hypothesized to increase the risk for overeating among restrained eaters. However, neurophysiological features of inhibitory control during negative mood states among restrained eaters are poorly understood. To address this gap, we aimed to assess event related potentials (ERPs) associated with food-specific inhibitory control among successful restrained eaters (SREs, n = 17), unsuccessful restrained eaters (UREs, n = 18), and non-restrained eaters (NREs, n = 18) engaged in a food-related go/no-go task during negative versus neutral mood states. Compared to neutral mood states, negative mood states were related to comparatively greater no-go N2a amplitudes in the entire sample. Regarding group differences, no-go N2a amplitudes of SREs were greater than those of UREs across negative and neutral mood states. However, no-go P3 amplitudes of SREs decreased significantly during the negative mood state while no change was observed for other groups. Results suggest that negative mood states may interfere with conflict monitoring and behavioral inhibition in general, but inhibitory control over food may be enhanced among SREs during negative mood states relative to UREs. Results may provide psychophysiological bases for understanding why SREs succeed and UREs fail in controlling appetitive responses to external food cues.

Relation between cognitive restraint and weight: Does a content validity problem lead to a wrong axis of care?

The aim of this research is to examine the relation between weight and cognitive restraint (CR), which is the intention to control food intake in order to maintain or lose weight, in a general French population sample. Is CR more prevalent in individuals with obesity than overweight, underweight or normal-weight subjects in this cross-sectional study? Are people affected by obesity non-restrained eaters? A total of 507 French people (80.2% women and 19.8% men), aged 18-78 years, responded to an online questionnaire. It appears that the most used questionnaire measuring CR has content validity problems as it seems to measure effective control and not the intention. Therefore, a numeric scale was used to answer the questions. Even if it is not possible in this study to test a causal link with latent variable modelling, our results seem to show that people with obesity more frequently intend to eat less or to eat healthier and/or to eat less sugar and fat than other people in order to control their weight. However, people affected by obesity do not succeed in so doing. These results raise the question of treatments advocating the increase of self-control. Finally, it would be necessary to obtain a real, scientific consensus on what CR is and on how to measure it in order to study the most effective treatments for people with overweight or obesity.

Smoking by young women with restrained eating following a food prime in the context of an alternative distractor.

Female smokers with elevated dietary restraint (high restrainers) may smoke more than nonrestrained eaters after a disinhibiting food event. The current study aimed to determine whether high restrainers smoke merely to distract themselves from unplanned eating or whether the weight-control aspects of smoking play a role. Primary aims were to test the effect of restraint status and a food prime on smoking and eating behavior in the presence of an alternative distractor (a computer tablet) and to examine the role of expectancies. Utilizing a between-subject design, female smokers (N = 128) were randomized to receive a milkshake prime (Prime condition) or not (No-Prime). They then received access to tempting foods, cigarettes, and the computer tablet. As expected, higher dietary restraint predicted shorter latency to smoke and craving to smoke but not latency to use the tablet. Additionally, a pattern of proximal expectancy subscales associated with weight/appetite control predicted cigarette consumption. Neither restraint nor expectancies interacted with condition to predict smoking behavior. Findings suggest that dietary restrainers attempt to prevent food consumption by turning to cigarettes, beyond preference for other salient distracting stimuli. Thus, smoking appears to function as more than simply a distractor from eating, and it is also associated with strong beliefs about weight and appetite control. Results offer implications for assessment and intervention among individuals presenting for smoking cessation treatment, particularly young adult women. Specifically, assessment of dietary restraint and expectancies related to weight and appetite aspects of smoking may be important to consider for tailored interventions. (PsycINFO Database Record

Conductas de control de peso en mujeres adolescentes dietantes y su relación con insatisfacción corporal y obsesión por la delgadez

IntroductionObsession with thinness and body dissatisfaction can lead adolescents to follow unsupervised diets, which could result in risky weight control behaviors such as fasting, vomiting, use of diuretics and laxatives. The aim of the current study is to examine weight control behaviors in dieting adolescents and relate them to body dissatisfaction (BD) and obsession with thinness (OT). MethodsA cross-sectional study was conducted on 439 adolescents from Valparaiso public schools to investigate risky weight control behaviors due to BD and OT scales from the Eating Disorders Inventory-2 (EDI-2), comparing restrained eaters and non-restrained eaters. ResultsA total of 43% adolescents had followed a weight loss diet without medical supervision. The dieters had higher BD and OT values. Moderate to severe food restriction, based on expert judgment, was observed in 29.6%, and differences in the presence and severity of purging behaviors were found between the 2 groups. ConclusionsOne third of the adolescents studied followed diets without professional supervision and had higher BD and OT values, as well as risky weight control behaviors. Overweight and obese adolescents followed more restrictive diets and developed riskier weight control behaviors.

Attentional Biases Toward Food-Related Information Among Restrained Eaters Based on the Goal Conflict Model of Eating

A considerable number of studies have identified selective attentional biases toward food-related information in restrained eaters. However, to date, the nature of information-processing biases that differentiate successful from unsuccessful restrained eaters has yet to be clarified. Based on Stroebe’s (2008) goal conflict model of eating, the current study was designed to investigate components of attentional bias among successful restrained eaters, unsuccessful restrained eaters, and non-restrained eaters under two conditions: a hedonic goal condition and a restrained goal condition. We hypothesized that within the hedonic goal condition, rapid avoidance would be observed in successful restrained eaters and disengagement difficulties would be displayed among unsuccessful restrained eaters. Conversely, within the restrained goal condition, rapid avoidance of palatable food cues would be present within both categories of restrained eating. From an initial sample of 907 Chinese undergraduate women, we recruited 60 successful restrained eaters, 60 unsuccessful restrained eaters and 60 non-restrained eaters based on scoring cut-offs from the Dutch Eating Behaviour Questionnaire (van Strien et al., 1986; 2007) to participate in dot probe research. In Experiment 1, a hedonic goal was activated prior to the dot probe task that featured palatable and neutral cues. Results of 3 (Group) × 3 (Prime Location) × 2 (Food Palatability) analyses of variance indicated disengagement difficulties related to palatable food cues among unsuccessful restrained eaters, rapid avoidance of these cues among successful restrained eaters, and no biases in responses to palatability cues among non-restrained eaters. In Experiment 2, a restrained goal was activated subliminally following hedonic goal activation before the dot probe task. Among unsuccessful restrained eaters, disengagement difficulties and rapid avoidance of palatable food cues. In successful restrained eaters, only rapid avoidance was shown. In conclusion, results indicated that successful restrained eaters showed a tendency to avoid palatable food cues while unsuccessful restrained eaters showed a tendency to approach to palatable food cues. On this basis, researchers should consider the distinction between successful and unsuccessful restrained eating when assessing attentional biases corresponding to restrained eating.

The effects of bulking, viscous and gel-forming dietary fibres on satiation

The objective was to determine the effects of dietary fibre with bulking, viscous and gel-forming properties on satiation, and to identify the underlying mechanisms. We conducted a randomised crossover study with 121 men and women. Subjects were healthy, non-restrained eaters, aged 18-50 years and with normal BMI (18.5-25 kg/m²). Test products were cookies containing either: no added fibre (control), cellulose (bulking, 5 g/100 g), guar gum (viscous, 1.25 g/100 g and 2.5 g/100 g) or alginate (gel forming, 2.5 g/100 g and 5 g/100 g). Physico-chemical properties of the test products were confirmed in simulated upper gastrointestinal conditions. In a cinema setting, ad libitum intake of the test products was measured concurrently with oral exposure time per cookie by video recording. In a separate study with ten subjects, 4 h gastric emptying rate of a fixed amount of test products was assessed by ¹³C breath tests. Ad libitum energy intake was 22 % lower for the product with 5 g/100 g alginate (3.1 (sd 1.6) MJ) compared to control (4.0 (sd 2.2) MJ, P< 0.001). Intake of the other four products did not differ from control. Oral exposure time for the product with 5 g/100 g alginate (2.3 (sd 1.9) min) was 48 % longer than for control (1.6 (sd 0.9) min, P= 0.01). Gastric emptying of the 5 g/100 g alginate product was faster compared to control (P< 0.05). We concluded that the addition of 5 g/100 g alginate (i.e. gel-forming fibre) to a low-fibre cookie results in earlier satiation. This effect might be due to an increased oral exposure time.

Effects of thought suppression on eating behaviour in restrained and non-restrained eaters

Recent research has shown that suppressing food related thoughts can cause a subsequent increase in consumption relative to groups not suppressing, or thinking about food. The present study examined whether the effects of thought suppression on subsequent eating behaviour would interact with participants restrained eating status. One hundred and sixteen female participants were split into three groups. One third suppressed thoughts of chocolate, one third thought about chocolate and the final third thought about anything they wished. Following this, participants took part in a task where they rated two brands of chocolate on several taste characteristics. Participants were unaware that the dependent variable was the amount of chocolate consumed and not taste preference. Participants also completed measures of dietary restraint, craving, guilt and thought suppression. Results indicated that restrained eaters in the suppression condition consumed significantly more chocolate than restrained eaters in the expression or control condition. Participants low on restraint ate statistically equivalent amounts in all three groups. In addition, participants reporting frequent use of thought suppression (assessed by the White Bear Suppression Inventory) reported greater chocolate cravings.

Body dissatisfaction mediates the relationship between self-esteem and restrained eating in female undergraduates.

Introduction Restrained eating is generally defined as a persistent fixation on dieting, weight, and food, such that the type and amount of food eaten is restricted for the purpose of weight loss or maintenance (Ruderman, 1985). Much to their dismay, restrained eaters commonly experience weight fluctuations, due to alternations between dieting and pronounced lapses in dietary adherence (Ruderman, 1985). Dietary restriction has been implicated as a risk factor in the development of obesity, binge-eating, and clinically diagnosable eating disorders, such as bulimia nervosa (Stice, Presnell, & Spangler, 2002). Although there are several qualitative differences in the psychological characteristics of restrained eaters and individuals with bulimia nervosa, there is evidence of similarities, including a willingness to describe oneself in negative terms, low self-esteem, heightened social anxiety, and body dissatisfaction (Striegel-Moore, Silberstein, & Rodin, 1993). Ruderman and Besbeas (1992) concluded that while dieting may not be the sole cause of bulimia nervosa, dietary restriction and lapses may be necessary for its development. Consequently, restricted eating and dietary lapses among restrained eaters should be studied with the ultimate goal of preventing eating disorders. Although preventing eating disorders is a key objective in researching restrained eaters, the restrained eating lifestyle also should be studied because of the distress it causes individuals in its own right. Much research indicates that when exposed to personally-relevant stressors, restrained eaters' eating becomes disinhibited, resulting in the consumption of significantly larger quantities of food than when not distressed (Heatherton, Striepe, & Wittenberg, 1998; Oliver, Huon, Zadro, & Williams, 2001; Tanofsky-Kraff, Wilfley, & Spurrell, 2000). Disinhibition itself is then an additional stressor, not only due to the potential weight gain caused by the overeating, but also because the disinhibited eating is perceived by restrained eaters as a reflection of their inability to control their eating. In turn, this may generalize to a broader feeling of personal inefficacy and low self-esteem (Polivy, Heatherton, & Herman, 1988). Interestingly, non-restrained eaters tend to eat less when distressed than when they are not distressed, albeit these findings are not quite as robust (Heatherton et al., 1998). Researchers have hypothesized that non-restrainers' appetites are suppressed as a result of stress. Restrained eating is a widespread problem with approximately 25% of college women describing themselves as restrainers (Rand & Kuldau, 1991). Thus, further study of the mechanisms and causes of the dietary disinhibition component is warranted. Evidence suggests that several factors may play an important role in the disinhibition effect, and yet there are many unknowns due to mixed findings across studies. One factor that may contribute to dietary disinhibition is self-esteem. The spiral explains the relationship between self-esteem and dietary restraint by suggesting that lowered self-esteem is caused by failed dietary restraint. Specifically, when restrainers consume more than they deem acceptable, they view themselves as failures with limited self-discipline. Such beliefs develop into general feelings of inefficacy and low self-esteem (Heatherton & Polivy, 1992; Polivy, et al., 1988). Lower self-esteem and feelings of inefficacy may lead to further lapses in dietary restraint, leading to even lower self-esteem. Thus, self-esteem spirals downwards as a function of restraint failure. A second model explaining the relationship between self-esteem and dietary restraint is the cognitive-behavioral model of bulimia nervosa (Vitousek, 1996). This model proposes that the link between self-esteem and dietary restraint is not direct, but is instead mediated by overconcern with weight and shape (Byrne & McLean, 2002). …

Changes in emotional state and cognition following administration of low-, medium- and high-energy foodstuff: the effect of dieting and dietary restraint

The aim of this study was to investigate changes in emotional state, food perception and cognition following administration of small quantities of low-, medium- or high-energy food. Thirty-eight female dieters and non-dieters aged 18–51 years (mean BMI=24.6 kg m−2) were asked to rate their emotional state before and after consumption and dietary restraint was determined using the Three-Factor Eating Questionnaire (Stunkard & Messick, 1985). The results showed that participants felt fuller and more energetic as energy content increased, whereas perception of “healthiness” and “safeness” of food decreased. Higher levels of anxiety were observed after ingestion of the medium-energy than after the low-energy food. Irrespective of the energy content, restrained eaters felt significantly more energetic than non-restrained eaters, whereas dieters reported significantly lower positive mood ratings than non-dieters following food administration. Although no significant effect of dietary restraint, dieting or energy content was observed on working memory, dieters’ performance was lower after consumption of a high-energy food. In conclusion, the study provided further evidence that energy content and psychological features of foods can alter emotional state and it can be tentatively suggested from these data that psychologically mediated changes in emotional responses to food and, more specifically, participants’ dieting behaviour should be taken into account when assessing the effects of nutrition on mood and cognition.

Smoking for weight control: Effect of priming for body image in female restrained eaters

Women are more likely than men to believe that smoking helps to control their weight, and this relationship may be more pronounced in those with eating disturbances, such as eating restraint. Restrained eaters have been shown to be more susceptible to media portrayals of idealized body image, like those used in tobacco advertising. The primary aim of this study was to examine the effect of an implicit prime for body image on expectations that smoking can control weight in restrained and non-restrained eaters. Participants were 40 females, who smoked an average of 7.65 (S.D. = 4.38) cigarettes per day. Participants were presented with a bogus task of rating slides; either participants viewed 30 slides of nature scenes (neutral prime); or viewed 30 slides depicting fashion models (body image prime). Participants then completed questionnaires that assessed smoking expectancies, smoking history, and eating restraint. As hypothesized, restrained eaters who viewed the slides depicting models had greater likelihood ratings that smoking helps to control appetite and manage weight, in comparison to restrained eaters who viewed the control slides and non-restrained eaters who viewed either type of slides. There were no other group differences across the remaining smoking expectancy factors. Images similar to those used in tobacco advertising targeting women had the ability to elicit stronger beliefs that smoking is beneficial for weight control in a group of women who are at heightened risk for such beliefs.

Counterregulatory eating behavior in multiple item test meals

Restrained eaters have been shown to disinhibit their eating when under stressful situations. However, the majority of laboratory studies that have demonstrated this effect utilized a single test food, typically ice cream. There is a lack of research investigating if this interaction is still evident when multiple foods are offered, and if so, the food choices that restrained and non-restrained eaters make when under stressful situations. The present study examined the impact of stress on food choices in individuals with varying degrees of restraint. Several classes of foods were offered (i.e., high fat/high sugar; low fat/high sugar; high fat/low sugar; low fat/low sugar). A total of 153 females were randomly assigned to either a stress or no-stress situation, and then both groups participated in a taste test. There was no significant difference in total amount of consumption between restrained and non-restrained eaters when under stress. However, further analyses found that restrained eaters under stress consumed more potato chips than those who were not under stress. Findings are discussed in terms of possible limitations of the stress-induced eating paradigm for restrained eaters.

Is beauty in the eye of the beholder?: Effects of weight and shape on attractiveness ratings of female line drawings by restrained and nonrestrained eaters

This study tested the differences between restrained and nonrestrained eaters' attractiveness perceptions of female line drawings, of their own figures, and the ideal female figure. Female line drawings varied systematically in body weight and in waist and hip circumference. Forty-six female undergraduate students, 23 nonrestrainers and 23 restrainers, rated stimuli in attractiveness, identified the figure which best represented their own body type (PAF), and the ideal body figure (IF) according to the Restraint Scale [RS; Herman, C. P., & Polivy, J. (1980). Restrained eating. In: A. Stunkard (Ed.), Obesity (pp. 208–225). Philadelphia, PA: Saunders]. Restrainers did not generally differ from nonrestrainers in attractiveness ratings or in their choice of IF. However, differences between IF and PAF were larger in restrainers than in nonrestrainers because restrainers chose PAFs with larger hips than nonrestrainers did. This difference between the restraint groups was independent of between-group differences in hip size. This discrepancy between IF and PAF may contribute to the restrainers' motivation to diet.

Indoor lighting preferences and bulimic behavior

Previous research suggests that evening constitutes a high-risk environment that increases the probability of binge eating and purging. One possible explanation for this finding is that exposure to dimmer light promotes behavioral disinhibition , thus undermining self-regulatory control and adherence to one's dietary standards, resulting in the disinhibited eating that is the hallmark of bulimia. Two studies ( n =245 and 156) tested the hypothesis that individual differences in preference for dimmer lighting while eating are directly associated with bulimic behavior in restrained eaters but unrelated to bulimic behavior in nonrestrained eaters. Undergraduates completed questionnaire measures of indoor lighting preferences, dietary restraint, bulimic behavior, and several other variables. Results of both studies showed that, as hypothesized, preference for dimmer light while eating correlated positively with bulimic behavior in restrained eaters ( r s between 0.31 and 0.58) but was unrelated to bulimic behavior in nonrestrained eaters. Study 3 found that participants who reported clinically significant levels of bulimic symptomatology preferred dimmer lighting while eating than did participants who were identical in dietary restraint but whose bulimic symptomatology was not clinically significant. The discussion applies Carver and Scheier's [Carver, C. S., & Scheier, M. F., 1998. On the self regulation of behaviour . Cambridge: Cambridge University Press] self-regulation theory to explain individual differences in lighting preference as they pertain to bulimia.

Memory bias for forbidden food cues in restrained eaters

Research on the cognitive patterns characteristic of women high in dietary restraint indicates an attentional bias favoring the early-stage selective processing of forbidden food words. The current study was conducted to determine whether highly restrained women also show a later stage memory bias for forbidden food words. Sixty-seven university females encoded a list of 30 words (15 forbidden food words, 15 animal control words) presented in an incidental learning task. Participants were then asked to freely recall as many words as they could remember. Scores on the Restraint Scale were used to classify participants as either high (N = 29) or low (N = 38) in dietary restraint. Contrary to prediction, high-restraint women did not remember more forbidden food words than low-restraint women. High-restraint women did, however, remember fewer animal control words than low-restraint women, suggesting a deficit in memory for material outside of the food-schema domain in restrained eaters relative to nonrestrained eaters. Consistent with hypothesis, only women in the high-restraint group remembered more forbidden food than animal control words, indicating a relative memory bias for forbidden food words only among restrained eaters. The results thus provide only partial support for Bemis-Vitousek and Hollon's theory that restrained eaters have cognitive structures (schema) which may support more elaborative encoding and/or greater memory accessibility of personally relevant (i.e., forbidden food) information and which may underlie self-reported food preoccupation among clinical and nonclinical restrained eaters.

The effects of sucrose and maize oil on subsequent food intake and mood

The effects of sucrose and oil preloads were explicitly compared in a single-blind controlled trial using a between-subjects design. Eighty adult subjects (forty-three male, thirty-seven female) aged 18-50 years received at 11.00 hours one of four yoghurt preloads. All were 80 g low-fat, unsweetened yoghurt (188 kJ), containing additionally (1) saccharin (control, 23 kJ), or (2) 40 g sucrose (859 kJ), (3) 40 g maize oil (1569 kJ), (4) 20 g sucrose, 20 g maize oil (1213 kJ). Subjects were normal eaters and of normal weight (male mean weight: 68.8 (SD 3.2) kg, BMI 21.8 (SD 1.6) kg/m2; female mean weight: 53.7 (SD 5.1) kg, BMI 20.4 (SD 1.2) kg/m2). Food intake was measured with a food diary and mood with ten single Likert scales. ANOVA was conducted using preload type (saccharin, sucrose, oil, sucrose + oil), sex (male, female) and early v. late breakfast times as factors. Mood was analysed using the same design, with time of rating (immediate, 60 min, 120 min) as an additional factor. Men ate more after the saccharin preload than after the other preloads, but did not vary the time of their next solid food. Women increased the intermeal interval only after the oil preload, which also had the highest energy content value, but did not vary the energy content of their next solid food. The saccharin preload decreased rated tiredness at 2 h compared with the sucrose preload, possibly due to its lower energy content. The preloads containing sucrose or sucrose + oil increased calmness between 1 and 2 h afterwards, compared with the saccharin preload. It is concluded that both sucrose and oil increase the intermeal interval in men, but that women are less sensitive to preloading. The mood effects suggest that tiredness after carbohydrate at 2 h may in part be a decrease in rated energy compared with the increased rated energy found after a preload with low energy content. Carbohydrate may genuinely increase calmness. These effects apply to non-restrained eaters of normal weight.

Dietary Restraint and the Selective Processing of Forbidden and Nonforbidden Food Words

The present study examined whether restrained eaters relative to nonrestrained eaters show greater preoccupation with forbidden foods than nonforbidden foods using a modified Stroop color-naming task. Fourteen restrained eaters and 14 nonrestrained eaters completed a computerized Stroop task, involving naming the ink color of forbidden food words, nonforbidden food words, and animal control words. Subjects also rated all food words on perceived “forbiddenness” (degree to which subjects were avoiding each food in efforts to control body weight). As hypothesized, Stroop interference for both types of food words was greater for restrained eaters than nonrestrained eaters. Contrary to hypothesis, restrained eaters did not demonstrate greater interference when color naming forbidden versus nonforbidden food words. However, restrained eaters rated only forbidden foods as more highly forbidden than nonrestrained eaters. The finding that dietary restraint was associated with the selective processing of both forbidden and nonforbidden food words may suggest that restrained eaters are more preoccupied with both types of foods than nonrestrained eaters. Alternatively, the Stroop may tap differences in the personal relevance of food cues between restrained eaters and nonrestrained eaters occurring early in the information processing chain, prior to restrained eaters' later classification of food words as bad versus good (forbidden vs. nonforbidden).

Acute effects of mycoprotein on subsequent energy intake and appetite variables

The effect of mycoprotein, a food produced by continuous fermentation of Fusarium graminearum (Schwabe), on energy intake and appetite was investigated. Female subjects, all classified as nonrestrained eaters, participated in two 3-d study periods. Subjects weighed food consumed on the day before the study, on the day of the meal, and on the following day. Subjects were presented with an isoenergetic meal containing either mycoprotein or chicken and visual analogue scales were completed immediately premeal, postmeal, and at hourly intervals for 3 h. Energy intake was significantly reduced the day of the study (by 24%) and the next day (by 16.5%) after eating mycoprotein compared with chicken. When measured 3 h after consumption, prospective food consumption and desire to eat decreased after mycoprotein compared with chicken. Evidence is increasing that fiber can have an effect on appetite and we have demonstrated that fiber-containing mycoprotein also has this affect.

Restrained and nonrestrained eaters' orienting responses to food and nonfood odors

Dietary restraint was assessed by Stunkard and Messick's (1985) three-factor eating questionnaire, using the restraint subfactor score only in normal-weight college students ( n = 41). The subjects were then assessed for skin conductance orienting responses (ORs) to food and nonfood odors when hungry and sated (after a standard breakfast and after an overnight fast). Subjects also rated their hunger and each odorant for pleasantness on separate 7-point scales. Results indicated that restrained eaters oriented less to odors than did nonrestrained subjects. Food deprivation did not differentially affect the ORs in restrained and nonrestrained eaters. The ORs, however, tended to be decreased in all of subjects who had had breakfast. Finally, nonrestrained subjects rated food and nonfood odors approximately equal in pleasantness, while the restrained eaters rated food odors as more pleasant than the nonfood odors. These results suggest that restrained eaters must certainly process odor stimuli related to foods, but also suggests that orienting to these salient (informative) cues is restricted. Perhaps in defense of the diet, restrained eaters learn methods/responses (cognitive strategies, instructional sets) to block orienting to food related cues such as odors.