Eating behavior following stress in women with and without bulimic symptoms

Daily stress and eating behaviors in adolescents and young adults: Investigating the role of cortisol reactivity and eating styles

Stress-related eating has been well documented in previous literature. However, there is limited research investigating the role of cortisol reactivity in daily stress-eating associations in samples of adolescents and young adults. 123 participants completed a baseline questionnaire and the Trier Social Stress Test in groups. Four saliva samples were taken at - 10, + 00, + 10 and + 40 min during the stress-induction task. Following this, participants completed an online daily diary each evening for 14 consecutive days to record daily stress and between-meal snack consumption. Multilevel modelling indicated that daily stress was positively associated with daily snack intake, particularly for ego-threatening and work/academic stressors. Emotional and external eating styles were found to moderate the stress-snacking relationship. Cortisol reactivity also moderated stress-eating associations, such that as cortisol reactivity levels increased from lower to higher levels, the impact of stress on eating decreased. The current findings highlight the importance of cortisol reactivity status and eating styles in understanding the complex relationship between daily stress and eating behavior in adolescents and young adults. Future research should continue investigating stress-eating associations in these groups and explore the role of other aspects of hypothalamic-pituitary-adrenal axis functioning.

Stress and eating behaviours in healthy adults: a systematic review and meta-analysis

Stress leads to detrimental health outcomes through direct biological and indirect behavioural changes. Stress can lead to disruption to normal eating behaviours, although the strength of these associations is unknown. This is the first meta-analysis to determine the strength of the stress-eating relationship in healthy adults and to explore the impact of potential moderators. Studies included had a clearly defined measure of stress (i.e., any noxious event or episode in one's environment with the exclusion of emotional distress) that was linked to non-disordered eating. Key terms were searched in Medline, PsycInfo and Ovid databases (23,104 studies identified). 54 studies (combined N = 119,820) were retained in the meta-analysis. A small, positive effect size was found for the stress-overall food intake relationship (Hedges' g = 0.114). Stress was associated with increased consumption of unhealthy foods (Hedges' g = 0.116) but decreased consumption of healthy foods (Hedges' g = -0.111). Only one significant moderator (restraint on stress-unhealthy eating) was identified. This meta-analysis identified the magnitude of the effect of stress on eating behaviour outcomes. Significant heterogeneity was observed that was not explained by the moderators examined. Further research on moderators of the stress-eating relationship is required and should distinguish effects for healthy versus unhealthy eating.

A Systematic Review of Genetic Polymorphisms Associated with Binge Eating Disorder

The genetic polymorphisms involved in the physiopathology of binge eating disorder (BED) are currently unclear. This systematic review aims to highlight and summarize the research on polymorphisms that is conducted in the BED. We looked for observational studies where there was a genetic comparison between adults with BED, in some cases also with obesity or overweight, and healthy controls or obesity/overweight without BED. Our protocol was written using PRISMA. It is registered at PROSPERO (identification: CRD42020198645). To identify potentially relevant documents, the following bibliographic databases were searched without a time limit, but until September 2020: PubMed, PsycINFO, Scopus, and Web of Science. In total, 21 articles were included in the qualitative analysis of the systematic review, as they met the eligibility criteria. Within the selected studies, 41 polymorphisms of 17 genes were assessed. Overall, this systematic review provides a list of potentially useful genetic polymorphisms involved in BED: 5-HTTLPR (5-HTT), Taq1A (ANKK1/DRD2), A118G (OPRM1), C957T (DRD2), rs2283265 (DRD2), Val158Met (COMT), rs6198 (GR), Val103Ile (MC4R), Ile251Leu (MC4R), rs6265 (BNDF), and Leu72Met (GHRL). It is important to emphasize that Taq1A is the polymorphism that showed, in two different research groups, the most significant association with BED. The remaining polymorphisms need further evidence to be confirmed.

Increased emotional eating during COVID-19 associated with lockdown, psychological and social distress

Due to the spread of COVID 2019, the Italian government imposed a lockdown on the national territory. Initially, citizens were required to stay at home and not to mix with others outside of their household (Phase 1); eventually, some of these restrictions were lifted (Phase 2). To investigate the impact of lockdown on emotional and binge eating, an online survey was conducted to compare measures of self-reported physical (BMI), psychological (Alexithymia), affective (anxiety, stress, and depression) and social (income, workload) state during Phase 1 and Phase 2. Data from 365 Italian residents showed that increased emotional eating was predicted by higher depression, anxiety, quality of personal relationships, and quality of life, while the increase of bingeing was predicted by higher stress. Moreover, we showed that higher alexithymia scores were associated by increased emotional eating and higher BMI scores were associated with both increased emotional eating and binge eating. Finally, we found that from Phase 1 to Phase 2 binge and emotional eating decreased. These data provide evidence of the negative effects of isolation and lockdown on emotional wellbeing, and, relatedly, on eating behaviour.

Stress as a potential moderator of ovarian hormone influences on binge eating in women

Previous research has demonstrated significant associations between increased levels of ovarian hormones and increased rates of binge eating (BE) in women. However, whereas all women experience fluctuations in ovarian hormones across the menstrual cycle, not all women binge eat in response to these fluctuations, suggesting that other factors must contribute. Stress is one potential contributing factor. Specifically, it may be that hormone-BE associations are stronger in women who experience high levels of stress, particularly as stress has been shown to be a precipitant to BE episodes in women. To date, no studies have directly examined stress as a moderator of hormone-BE associations, but indirect data (that is, associations between BE and stress and between ovarian hormones and stress) could provide initial clues about moderating effects. Given the above, the purpose of this narrative review was to evaluate these indirect data and their promise for understanding the role of stress in hormone-BE associations. Studies examining associations between all three phenotypes (that is, ovarian hormones, stress, and BE) in animals and humans were reviewed to provide the most thorough and up-to-date review of the literature on the potential moderating effects of stress on ovarian hormone-BE associations. Overall, current evidence suggests that associations between hormones and BE may be stronger in women with high stress levels, possibly via altered hypothalamic-pituitary-adrenal axis response to stress and increased sensitivity to and altered effects of ovarian hormones during stress. Additional studies are necessary to directly examine stress as a moderator of ovarian hormone-BE associations and identify the mechanisms underlying these effects.

Emotional eating and instructed food-cue processing in adolescents: An ERP study

We examined the P3 (250-500ms) and Late Positive Potential (LPP; 500-2000ms) event-related potentials (ERPs) to food vs. nonfood cues among adolescents reporting on emotional eating (EE) behavior. Eighty-six adolescents 10-17 years old were tested using an instructed food versus nonfood cue viewing task (imagine food taste) during high-density EEG recording. Self-report data showed that EE increased with age in girls, but not in boys. Both P3 and LPP amplitudes were greater for food vs. nonfood cues (food-cue bias). Exploratory analyses revealed that, during the LPP time period, greater EE was associated with a more positive food-cue bias in the fronto-central region. This heightened fronto-central food-cue bias LPP is in line with a more activated prefrontal attention system. The results suggest that adolescents with higher EE may engage more top-down cognitive resources to regulate their automatic emotional response to food cues, and/or they may exhibit greater reward network activation to food cues than do adolescents with lower EE, even in the absence of an emotional mood induction.

Dietary restraint: what's the harm? A review of the relationship between dietary restraint, weight trajectory and the development of eating pathology

Dietary restraint has historically been implicated as a risk factor for the development of eating pathology. Despite existing findings, recent research suggests that many individuals are capable of practicing dietary restraint without negative effects. In order to successfully incorporate the positive aspects of dietary restraint into interventions for healthy weight management, a nuanced examination of the relationship between dietary restraint and resulting eating patterns is necessary. Accordingly, the current review seeks to clarify the existing literature with regard to dietary restraint. First, this review examines the construct of dietary restraint and differentiates dietary restraint from related constructs, such as weight loss dieting. Second, it identifies situations in which dietary restraint has been linked with positive outcomes, such as healthy weight management and prevention of eating pathology. Altogether, it appears that dietary restraint can prove a beneficial strategy for those attempting to control their weight, as it does not relate to increased levels of eating pathology when practiced as part of a well-validated weight management programme.

Behavioral and neurodevelopmental precursors to binge-type eating disorders: support for the role of negative valence systems

BACKGROUND

Pediatric loss-of-control (LOC) eating is a robust behavioral precursor to binge-type eating disorders. Elucidating precursors to LOC eating and binge-type eating disorders may refine developmental risk models of eating disorders and inform interventions.

METHOD

We review evidence within constructs of the Negative Valence Systems (NVS) domain, as specified by the Research Domain Criteria framework. Based on published studies, we propose an integrated NVS model of binge-type eating-disorder risk.

RESULTS

Data implicate altered corticolimbic functioning, neuroendocrine dysregulation, and self-reported negative affect as possible risk factors. However, neuroimaging and physiological data in children and adolescents are sparse, and most prospective studies are limited to self-report measures.

CONCLUSIONS

We discuss a broad NVS framework for conceptualizing early risk for binge-type eating disorders. Future neural and behavioral research on the developmental trajectory of LOC and binge-type eating disorders is required.

Urinary cortisol and psychopathology in obese binge eating subjects

BACKGROUND

Investigations on the relationship between obesity, binge eating and the function of hypothalamic-pituitary-adrenal (HPA) axis have led to inconsistent results. General psychopathology affects HPA axis function. The present study aims to examine correlations between binge eating, general psychopathology and HPA axis function in obese binge eaters.

METHODS

Twenty-four hour urinary free cortisol (UFC/24 h) was measured in 71 obese binge eating women. The patients were administered psychometric tests investigating binge eating, psychopathology and clinical variables. The relationship between binge eating, psychopathology and urinary cortisol was investigated, controlling for age and BMI.

RESULTS

We found an inverse correlation between UFC/24 h and binge eating, depression, obsessive-compusive symptoms, somatization and sensitivity. In a regression model a significant inverse correlation between urinary cortisol and psychopathology was confirmed.

CONCLUSIONS

Urinary cortisol levels in obese patients with binge eating disorder show an inverse correlation with several dimensions of psychopathology which are considered to be typical of a cluster of psychiatric disorders characterized by low HPA axis function, and are very common in obese binge eating patients. If these results are confirmed, UFC/24 h might be considered a biomarker of psychopathology in obese binge eaters.

Satiety-related hormonal dysregulation in behavioral variant frontotemporal dementia

OBJECTIVE

To investigate whether patients with behavioral variant frontotemporal dementia (bvFTD) have dysregulation in satiety-related hormonal signaling using a laboratory-based case-control study.

METHODS

Fifty-four participants (19 patients with bvFTD, 17 patients with Alzheimer disease dementia, and 18 healthy normal controls [NCs]) were recruited from a tertiary-care dementia clinic. During a standardized breakfast, blood was drawn before, during, and after the breakfast protocol to quantify levels of peripheral satiety-related hormones (ghrelin, cortisol, insulin, leptin, and peptide YY) and glucose. To further explore the role of patients' feeding abnormalities on hormone levels, patients were classified into overeating and nonovereating subgroups based on feeding behavior during separate laboratory-based standardized lunch feeding sessions.

RESULTS

Irrespective of their feeding behavior in the laboratory, patients with bvFTD, but not patients with Alzheimer disease dementia, have significantly lower levels of ghrelin and cortisol and higher levels of insulin compared with NCs. Furthermore, while laboratory feeding behavior did not predict alterations in levels of ghrelin, cortisol, and insulin, only patients with bvFTD who significantly overate in the laboratory demonstrated significantly higher levels of leptin compared with NCs, suggesting that leptin may be sensitive to particularly severe feeding abnormalities in bvFTD.

CONCLUSIONS

Despite a tendency to overeat, patients with bvFTD have a hormonal profile that should decrease food intake. Aberrant hormone levels may represent a compensatory response to the behavioral or neuroanatomical abnormalities of bvFTD.

Beneficial Effects of a Protein Free, High Carbohydrate Meal on Rat Coping Behavior and Neurotransmitter Levels During Heat Stress

This study examined effects of a single protein-free (PROT-free), high carbohydrate meal (0% protein, 82% carbohydrate) or control meal (20% protein, 62% carbohydrate) on coping behavior and neurotransmitter levels of male Fischer 344 rats. Meals varying in protein/carbohydrate ratio differentially affect transport of neurotransmitter precursors into the brain and alter neurotransmission. The meals were studied in animals exposed to heat stress and normothermic control animals. Coping behavior was assessed using the Porsolt swim test (N = 39). In other rats, dopamine (DA), epinephrine (EPI), norepinephrine (NE) and serotonin in the striatum were assessed using in vivo microdialysis (N = 35). In control-fed rats, heat stress impaired Porsolt performance in comparison to normothermic controls (p <0.05). The PROT-free, high carbohydrate meal protected animals from adverse effects of stress on coping performance as it reduced the effect of heat stress more than 90%. Significant changes in striatal DA and EPI efflux were observed as a consequence of the nutritional manipulation and heat exposure. It is concluded a single PROT-free, high carbohydrate meal improves ability to cope with heat stress and alters neurotransmission. The neurochemical basis for these effects may be a change in DA efflux, although other mechanisms cannot be ruled out.

Cortisol response and desire to binge following psychological stress: comparison between obese subjects with and without binge eating disorder

While stress and negative affect are known to precede "emotional eating", this relationship is not fully understood. The objective of this study was to explore the relationship between induced psychological stress, hypothalamic-pituitary-adrenal (HPA) axis activity, and eating behavior in binge eating disorder (BED). The Trier Social Stress Test (TSST) was applied in obese participants with (n=8) and without BED (n=8), and normal weight controls (n=8). Psychological characteristics, eating-related symptoms, and cortisol secretion were assessed. Baseline stress, anxiety and cortisol measures were similar in all groups. At baseline desire to binge was significantly higher among the BED group. While the TSST induced an increase in cortisol levels, a blunted cortisol response was observed in the BED group. In the BED group, a positive correlation was found between cortisol (area under the curve) levels during the TSST and the change in VAS scores for desire to binge. Post-TSST desire to binge and sweet craving were significantly higher in the BED group and correlated positively with stress, anxiety, and cortisol response in the BED group only. These results suggest chronic down-regulation of the HPA axis in participants with BED, and a relationship between psychological stress, the acute activation of the HPA axis, and food craving.

Emotion and eating disorder symptoms in patients with anorexia nervosa: an experimental study

OBJECTIVE

To evaluate the effect of negative emotion on self-reported eating disorder symptoms and objectively-measured eating behavior in patients with anorexia nervosa (AN).

METHOD

Twenty-eight females with AN were randomized to a negative or neutral mood induction followed by a test meal. Participants completed assessments one week before the experimental session, before (pretest) and after (posttest) the mood induction, and after the test meal.

RESULTS

Participants in the negative emotion condition had an increase in negative affect from pretest to posttest that was accompanied by significantly greater increases in self-reported eating disorder symptoms than were exhibited by participants in the neutral emotion condition, who had no increase in negative affect. There was no effect of emotion condition on eating behavior.

DISCUSSION

Results suggest that negative emotions influence the expression of cognitive eating disorder symptoms in individuals with AN, which may have implications for the identification of treatment targets.

Salivary cortisol and binge eating disorder in obese women after surgery for morbid obesity

BACKGROUND

Binge eating episodes characterized by loss of control are hypothesized to be accompanied by changes in hypothalamic pituitary adrenal (HPA) axis functioning. Cortisol is an end product of this neuroendocrine stress system.

PURPOSE

The aim of this study was to examine the cortisol levels and the awakening cortisol response (ACR) in obese persons showing binge eating after surgery for morbid obesity.

METHOD

Sixteen obese women with binge eating disorder (BED) and 18 obese women without BED participated in the study. Means+/-SD: age 43 +/- 15, body mass index 40 +/- 8. Salivary cortisol, anthropometric assessments, and the eating disorder examination interview were taken.

RESULTS

Women with BED showed a significantly lower waist-to-hip ratio and cortisol levels during the day than women without BED, whereas the ACR did not differ.

CONCLUSION

Our cross-sectional study in a small sample generates the hypothesis that neuroendocrine regulation differs between obese women with and without BED after obesity surgery. This finding needs replication in future studies that should also examine the causal direction of the observed association.

Impact of stressors in a natural context on release of cortisol in healthy adult humans: a meta-analysis

Increased hypothalamic-pituitary-adrenal (HPA) activation, culminating in elevated circulating cortisol levels is a fundamental response to stressors. In animals, this neuroendocrine change is highly reliable and marked (approximately 5-10-fold elevations), whereas in humans, the increase of cortisol release is less pronounced, and even some potent life-threatening events (anticipation of surgery) only elicit modest cortisol increases. Meta-analysis of factors that influenced the increase of cortisol release in a laboratory context pointed to the importance of social evaluative threats and stressor controllability in accounting for the cortisol rise. The present meta-analysis, covering the period from 1978 through March 2007, was undertaken to identify the factors most closely aligned with cortisol increases in natural settings. It appeared that stressor chronicity was fundamental in predicting cortisol changes; however, this variable is often confounded by the stressor type, the stressor's controllability, as well as contextual factors, making it difficult to disentangle their relative contributions to the cortisol response. Moreover, several experiential factors (e.g. previous stressor experiences) may influence the cortisol response to ongoing stressors, but these are not readily deduced through a meta-analysis. Nevertheless, there are ample data suggesting that stressful events, through their actions on cortisol levels and reactivity, may influence psychological and physical pathology.

The moderating effect of avoidant coping on restrained eaters' risk for disinhibited eating: implications for dietary relapse prevention

Avoidant coping style was tested as a moderating variable for the effect of ego threat on chronic dieters' (restrained eaters) risk for disinhibited eating. Young women (n=146) were randomly assigned to a speech threat or to a no threat condition and then participated in a bogus ice cream taste test. Analyses of covariance revealed that restrained eaters who scored higher on a standardized measure of avoidant coping consumed significantly more ice cream than restrained eaters who scored lower on avoidant coping regardless of the threat condition to which they were assigned. The findings suggest that dieters prone to using avoidant coping strategies may be particularly vulnerable to overeating and, therefore, could be at risk for lapses in dietary restraint. Hence, dietary relapse prevention programs might target dieters who tend to use avoidant coping strategies for cognitive-behavioral therapy to teach them adaptive coping skills.

Stress response and binge eating disorder

In clinical practice, obese patients report stress as a primary trigger for binge eating. However, the biological mechanism underlying this relationship is poorly understood. This paper presents, a theoretical overview of how cortisol secretion, a major component of the stress response, could play a role in binge eating, given that exogenous glucocorticoids can lead to obesity by increasing food intake. I will discuss findings from recent studies demonstrating links between laboratory stress, cortisol, food intake and abdominal fat in humans. Cortisol is elevated following laboratory stressors in women with anorexia nervosa (AN), bulimia nervosa (BN), and obesity, but has not been widely studied in women with binge eating disorder (BED). Additionally, I will review recent findings demonstrating a greater cortisol response to stress in obese women with BED compared to non-BED.

The effect of glucose and mental stress on cutaneous microvascular endothelial function

Glucose and mental stress, independently, have been found to impair arterial endothelial function (an indicator of vascular health). The present study sought to determine whether the combination of glucose and stress would have a greater effect on microvascular endothelial function than each on its own. To assess endothelial function, surges in skin blood flow (reactive hyperemia), following the release of cuff pressure to the upper arm at 200 mmHg for 5 min, were measured with laser Doppler flowmetry in 40 young, healthy females. Endothelial function did not change significantly following a 5-min mathematics stressor or the consumption of 75 g of glucose. However, the combination of glucose and stress impaired endothelium-dependent dilatation 30 min after glucose consumption. These findings suggest that combinations of vascular risk factors may be more threatening to cardiovascular health than singularly occurring factors.

Cortisol Stress Response Is Positively Correlated with Central Obesity in Obese Women with Binge Eating Disorder (BED) before and after Cognitive-Behavioral Treatment

Stress is the most commonly reported trigger of binge eating, and high cortisol levels are positively related to both central body fat and food intake after laboratory stress. We therefore examined waist circumference (WHR) and cortisol stress responsivity after a cold pressor stress test (CPT) in 22 obese (BMI > 27) women (11 BED, 11 non-BED). BMI and WHR did not differ between groups. The BED group had higher morning basal cortisol than the non-BED group (P = .03) and greater AUC cortisol after CPT, after controlling for AUC insulin (P = .04). In the BED group, WHR was related to AUC cortisol (P = .002) and peak cortisol stress responsivity (P = .003). Twenty (10 non-BED, 10 BED) were randomized to a 6-week treatment program (CBT + Diet) or Wait-List (WL) control group. There were no BED group or treatment-group differences in WHR, morning basal cortisol, or AUC cortisol after CPT. The relationship between WHR and both AUC cortisol (P = .002) and peak cortisol stress responsivity after CPT (P = .008) remained significant in the BED group. In BED, there is a hyperactive HPA axis related to abdominal obesity that persists even after treatment, suggesting that cortisol might be a primary factor in the disorder.

Cortisol, hunger, and desire to binge eat following a cold stress test in obese women with binge eating disorder

OBJECTIVE

Increased basal cortisol levels have been found in bulimia nervosa. After stress, increased cortisol levels have been associated with increased food intake in healthy women. Therefore, we assessed cortisol, hunger, and desire to binge eat after a cold pressor test (CPT) among women with binge eating disorder (BED).

METHODS

Twenty-two obese (body mass index [BMI] = 36.7 +/- 6.5 SD) females (11 non-BED, 11 BED) completed the Zung depression scale and underwent the CPT, hand submerged in ice water for 2 minutes. Over 60 minutes, periodic ratings of hunger and desire to binge eat were obtained, just before blood draws for cortisol, as well as insulin. On a separate day, participants had a 1-mg oral dexamethasone suppression test (DST).

RESULTS

The BED group had higher depression scores than the non-BED (p = .04), but depression was not a significant covariate for the cortisol response or to DST. After controlling for contraceptive use (n = 3), the BED group had higher basal cortisol than the non-BED group (p = .03), but cortisol did not differ after DST (p = .40). The BED group had nearly significant greater cortisol AUC after the CPT (p = .057) after controlling for insulin AUC and contraceptive use (p = .057). The BED group also had greater AUC for hunger (p = .03) and desire to binge eat (p = .02) after the CPT.

CONCLUSION

These findings support our hypothesis of a hyperactive HPA-axis in BED, which may contribute to greater hunger and binge eating.

Do changes in mood and concerns about weight relate to smoking relapse in the postpartum period?

The majority of women who quit smoking during pregnancy will resume smoking during the postpartum period. Little is known, however, about the predictors of postpartum relapses to smoking. Changes in mood and increases in concerns about weight are common during the postpartum period, and these factors may affect women's postpartum smoking behavior. In this paper, we present a model of the relationship among mood, weight concerns and postpartum smoking. Data from previous postpartum relapse prevention trials are reviewed and evidence of a connection between changes in mood and weight concerns to postpartum relapse is presented. Directions for future research on the prevention of smoking relapses during the postpartum period, and the roles of mood and weight concerns in smoking relapse are presented.

Effects of chronic restraint stress on feeding behavior and on monoamine levels in different brain structures in rats

Monoaminergic systems are important modulators of the responses to stress. Stress may influence feeding behavior, and the involvement of monoamines in the control of food intake is well recognized. We investigated the effects induced by chronic-restraint stress, 1 h a day, for 40 days, on eating behavior and on monoamines in distinct brain structures. Increased consumption of sweet pellets, and not of peanuts, was observed. Dopamine (DA), serotonin (5-HT), and their metabolites were measured by HPLC-EC. After chronic restraint, the results observed were decreased 5-HT in hippocampus, with increased 5-HIAA/5-HT; decreased 5-HIAA levels in cortex; reduction in DA in hippocampus, and increased levels in amygdala and hypothalamus; HVA increased in cortex, as well as HVA/DA ratio, while DOPAC/DA decreased. HVA decreased in hypothalamus, as well as HVA/DA, and DOPAC/DA and HVA/DA decreased in the amygdala. These results suggest that restraint stress differentially affects the activity of central dopaminergic and serotonergic neurons, and this may be related to the effects observed in eating behavior.

Carbohydrate ingestion, blood glucose and mood

A series of studies have reported that a high carbohydrate meal, or diets high in carbohydrate, were associated with feeling less energetic. However, after a drink containing pure sugar most studies report no effect. Meals almost exclusively carbohydrate increase the availability of tryptophan and hence serotonin synthesis in the brain, however, a small amount of protein blocks this mechanism making it an uncommon response. In many individuals, poor mood stimulates the eating of palatable high carbohydrate/high fat foods that stimulate the release of endorphins. There is a tendency for those with lower blood glucose, when performing cognitively demanding tasks, to report poorer mood. In a range of situations an association between a tendency for blood glucose levels to fall rapidly, and irritability, has been found. Differences in the ability to control blood glucose levels influence the association between carbohydrate intake and mood. There is a need in future research to contrast the impact of carbohydrate on mood in those distinguished because of their pre-existing psychological and physiological functioning.

The Yale Interpersonal Stressor (YIPS): affective, physiological, and behavioral responses to a novel interpersonal rejection paradigm

Given links between interpersonal functioning and health as well as the dearth of truly interpersonal laboratory stressors, we present a live rejection paradigm, the Yale Interpersonal Stressor (YIPS), and examine its effects on mood, eating behavior, blood pressure, and cortisol in two experiments. The YIPS involves one or more interaction(s) between the participant and two same-sex confederates in which the participant is made to feel excluded and isolated. In Experiment 1, 50 female undergraduates were randomly assigned to the YIPS or a control condition. Participants in the YIPS condition experienced greater negative affect and less positive affect than did those in the control condition. Further, restrained eaters ate more following the YIPS than did nonrestrained eaters. In Experiment 2, 25 male and female undergraduates completed the YIPS. The YIPS induced significant increases in tension, systolic blood pressure (SBP), and diastolic blood pressure (DBP) from baseline, while significantly decreasing positive affect. The YIPS appeared particularly relevant for women, resulting in significantly greater increases in cortisol and SBP for women compared to men. The YIPS, then, provides an alternative to traditional, achievement-oriented laboratory stressors and may allow for the identification of individuals most vulnerable to interpersonal stress.

Interaction between repeated restraint stress and concomitant midazolam administration on sweet food ingestion in rats

Emotional changes can influence feeding behavior. Previous studies have shown that chronically stressed animals present increased ingestion of sweet food, an effect reversed by a single dose of diazepam administered before testing the animals. The aim of the present study was to evaluate the response of animals chronically treated with midazolam and/or submitted to repeated restraint stress upon the ingestion of sweet food. Male adult Wistar rats were divided into two groups: controls and exposed to restraint 1 h/day, 5 days/week for 40 days. Both groups were subdivided into two other groups treated or not with midazolam (0.06 mg/ml in their drinking water during the 40-day treatment). The animals were placed in a lighted area in the presence of 10 pellets of sweet food (Froot loops). The number of ingested pellets was measured during a period of 3 min, in the presence or absence of fasting. The group chronically treated with midazolam alone presented increased ingestion when compared to control animals (control group: 2.0 +/- 0.44 pellets and midazolam group: 3.60 +/- 0.57 pellets). The group submitted to restraint stress presented an increased ingestion compared to controls (control group: 2.0 +/- 0.44 pellets and stressed group: 4.18 +/- 0.58 pellets). Chronically administered midazolam reduced the ingestion in stressed animals (stressed/water group: 4.18 +/- 0.58 pellets; stressed/midazolam group: 3.2 +/- 0.49 pellets). Thus, repeated stress increases appetite for sweet food independently of hunger and chronic administration of midazolam can decrease this behavioral effect.

Stress, dietary restraint and food intake

OBJECTIVE

The purpose of this study was to examine the associations between work stress and nutritional status in relation to dietary restraint in a community sample of adults.

METHODS

The design included a cross-sectional and a longitudinal study element. Ninety staff members (58 women and 32 men) of a large department store were assessed on four occasions over a 6-month period with measures of diet, weight, and perceived stress. Work stress was indexed in terms of the hours of work over the past 7 days, which provided an objective indicator of demand.

RESULTS

Participants worked an average of 47 hours on the high-work-stress session compared with 32 hours on the low-work-stress session. The highest work-stress session was compared with the lowest work-stress session in the longitudinal analyses, and the moderating effects of gender and restrained eating were examined. High-workload periods were associated with higher energy and saturated fat and sugar intake. There was a significant moderating effect of restrained eating, with a hyperphagic response to work stress in restrained eaters, compared with no effect in unrestrained eaters.

CONCLUSION

The results indicate that the associations between restraint and stress-induced eating that have been observed in the laboratory extend to the real-life setting. They raise the possibility that restrained eaters are particularly vulnerable to adverse effects of stress on health, through influences on food intake.

To eat or not to eat: affective and physiological mechanisms in the stress-eating relationship

The current study aggregated methods from the cardiovascular reactivity and dietary restraint paradigms in an attempt to advance our understanding of stress-induced eating behavior. Seventy-seven female subjects completed a protocol consisting of distinct baseline, stress-induction, and recovery phases during which we monitored blood pressure, heart rate, and self-reported affect. Food was inconspicuously made available to participants during the recovery phase. Our results replicated the restraint x affect level interaction observed in the restraint literature, while showing that physiological measures could further explain distressed eating behavior. Physiological arousal was found reliably to predict reduced food consumption, but only among unrestrained eaters. Analysis of the recovery data showed that food consumption was associated with impaired physiological recovery rates for restrained but not for unrestrained participants. We believe that our results help to reconcile findings in the stress, eating, and dietary restraint fields and offer support for recently developed theories of stress-induced overeating.

Interaction of stress, smoking, and dietary restraint in women

Smoking cessation often results in weight gain but certain subtypes of smokers may be more likely than others to gain weight. Women high in dietary restraint ("restrainers") increase food intake and gain more weight than nonrestrainers during smoking cessation. Restrainers have also been reported to increase food intake following laboratory stressors. Therefore, the present study was designed to measure the influence of stress on food intake and subjective distress during acute smoking abstinence in restrained and nonrestrained women. Participants were 48 women, 18-40 years old, comprising six groups (n = 8 per group) in a 2 x 3 x 2 design. Groups consisted of two levels of restraint (restrained and nonrestrained) and three levels of smoking (ad lib. smokers, abstinent smokers, and nonsmokers), whereas the within-participant manipulation involved two sessions differing in stress (stress and control). Snack foods were available for consumption. Results showed that distress, measured by the Stress-Arousal Checklist and visual analogue measures of tension and anxiety, was higher in the stress session for all groups except for restrainers who smoked ad lib. Furthermore, distress was significantly higher in smoke-abstinent restrainers during the stress session than all other conditions. However, despite differences in distress, no effect was observed for food intake. Desire for a cigarette showed a sharper increase over the stress session for restrainers compared with nonrestrainers but did not differ in the control session. These data suggest that restrainers may use smoking to reduce distress and may increase smoking, but not eating, during stress.