Self-reported dieting success is associated with cardiac autonomic regulation in current dieters

Evaluating campaign concepts aimed at replacing sugar-sweetened beverages with water

ISSUE ADDRESSED

The study addresses the global health concern of sugar overconsumption, particularly focusing on the prevalence of sugar-sweetened beverage consumption among young people.

METHODS

The study tested three different health promotion campaign concepts, designed to reduce sugar-sweetened beverage intake and promote water consumption as a healthier alternative. A total of 402 young adults (18-29) were recruited from a university campus and an online panel. Participants were randomly assigned to view one of three campaign images: one advocating for substituting sugar-sweetened beverages with water, and two exclusively promoting water consumption. These images were assessed through an online survey, which included questions on emotional response, salience, attitudes and intentions towards various beverages.

RESULTS

Participants exposed to the campaign emphasising the benefits of water showed a greater intention to increase water consumption and reduce both sugar- and non-sugar-sweetened beverages compared with the other groups. There were no significant differences observed for the beverage choice task across the campaigns.

CONCLUSIONS

The findings suggest that messaging focusing on the benefits of water holds promise in encouraging healthier beverage consumption intentions among young adults. The lack of significant differences in the beverage choice task across the campaigns indicates a need for further research to explore long-term behaviour change effects. SO WHAT?: By highlighting the benefits of water consumption, campaigns may have the potential to positively influence beverage choices and promote healthier habits. Continued research in this area can provide valuable insights for developing more impactful interventions aimed at reducing sugar-sweetened beverage consumption.

On the measurement and correlates of plate clearing: examining a German version of the Plate Clearing Tendency Scale

PURPOSE

Plate clearing-eating a meal in its entirety-is common and may be a factor contributing to obesity. For the assessment of individual differences in plate clearing tendencies, Robinson et al. (Obesity 23:301-304, 2015) developed the Plate Clearing Tendency Scale (PCTS). However, little is known about the psychometric properties of this scale and its correlates.

METHODS

In the current study, participants (N = 207, 76% female) completed a German translation of the PCTS and other questionnaires online.

RESULTS

A one-factor structure had good model fit and the PCTS had acceptable internal reliability and good test-retest reliability across an average of four and a half weeks. Higher plate clearing tendencies related to more frequent parental encouragement to clear one's plate in childhood and to stronger food waste concerns but were unrelated to sex, body weight, self-control, and eating behaviors. However, higher plate clearing tendencies related to higher body weight in unsuccessful dieters.

CONCLUSION

The current study shows that the PCTS has sound psychometric properties and that plate clearing tendencies appear to be largely driven by food waste concerns and not by automatic eating habits or low eating-related self-control. In dieters, however, high plate clearing tendencies may contribute to low dieting success and hinder weight loss.

LEVEL OF EVIDENCE

No level of evidence, basic science.

Resting state heart rate variability in clinical and subthreshold disordered eating: A meta-analysis

OBJECTIVE

Research has demonstrated mixed results regarding the direction of the association between vagal activation and disordered eating. The current meta-analysis examined studies testing the link between resting-state heart rate variability indices of vagal activation (vmHRV), and both clinical and subthreshold disordered eating.

METHOD

A systematic search of the literature resulted in the inclusion of studies that were correlational (associations between HRV and disordered eating symptoms) and that examined group differences (e.g., control group vs. disordered eating group), for a total of 36 samples.

RESULTS

Findings indicated a small but reliable association of vmHRV with disordered eating, r = 0.12, indicating greater vagal activation in individuals with disordered eating compared to those with little or no disordered eating behavior. Moderation analyses identified predictors of the vmHRV/disordered eating association. Bulimia nervosa was found to have a large, positive effect size with vmHRV, r = 0.60, which was significantly greater than all other types of disordered eating, Q _T = 10.74, p = .047. Compared to subthreshold disordered eating, clinical eating disorders demonstrated significant, persistent increased vagal activation with a medium, reliable effect size, r = 25, Q_T = 3.94, p = .045.

CONCLUSION

These insights contribute to an improved understanding of the pathophysiology in disordered eating.

Food Addiction Symptoms and Amygdala Response in Fasted and Fed States

Few studies have investigated the underlying neural substrates of food addiction (FA) in humans using a recognised assessment tool. In addition, no studies have investigated subregions of the amygdala (basolateral (BLA) and central amygdala), which have been linked to reward-seeking behaviours, susceptibility to weight gain, and promoting appetitive behaviours, in the context of FA. This pilot study aimed to explore the association between FA symptoms and activation in the BLA and central amygdala via functional magnetic resonance imaging (fMRI), in response to visual food cues in fasted and fed states. Females (n = 12) aged 18-35 years completed two fMRI scans (fasted and fed) while viewing high-calorie food images and low-calorie food images. Food addiction symptoms were assessed using the Yale Food Addiction Scale. Associations between FA symptoms and activation of the BLA and central amygdala were tested using bilateral masks and small-volume correction procedures in multiple regression models, controlling for BMI. Participants were 24.1 ± 2.6 years, with mean BMI of 27.4 ± 5.0 kg/m² and FA symptom score of 4.1 ± 2.2. A significant positive association was identified between FA symptoms and higher activation of the left BLA to high-calorie versus low-calorie foods in the fasted session, but not the fed session. There were no significant associations with the central amygdala in either session. This exploratory study provides pilot data to inform future studies investigating the neural mechanisms underlying FA.

Heart-rate variability: a biomarker to study the influence of nutrition on physiological and psychological health?

As the influence of diet on health may take place over a period of decades, there is a need for biomarkers that help to identify those aspects of nutrition that have either a positive or a negative influence. The evidence is considered that heart-rate variability (HRV) (the time differences between one beat and the next) can be used to indicate the potential health benefits of food items. Reduced HRV is associated with the development of numerous conditions for example, diabetes, cardiovascular disease, inflammation, obesity and psychiatric disorders. Although more systematic research is required, various aspects of diet have been shown to benefit HRV acutely and in the longer term. Examples include a Mediterranean diet, omega-3 fatty acids, B-vitamins, probiotics, polyphenols and weight loss. Aspects of diet that are viewed as undesirable, for example high intakes of saturated or trans-fat and high glycaemic carbohydrates, have been found to reduce HRV. It is argued that the consistent relationship between HRV, health and morbidity supports the view that HRV has the potential to become a widely used biomarker when considering the influence of diet on mental and physical health.

A Pilot Study on the Effects of Slow Paced Breathing on Current Food Craving

Heart rate variability biofeedback (HRV-BF) involves slow paced breathing (approximately six breaths per minute), thereby maximizing low-frequent heart rate oscillations and baroreflex gain. Mounting evidence suggests that HRV-BF promotes symptom reductions in a variety of physical and mental disorders. It may also positively affect eating behavior by reducing food cravings. The aim of the current study was to investigate if slow paced breathing can be useful for attenuating momentary food craving. Female students performed paced breathing either at six breaths per minute (n = 32) or at nine breaths per minute (n = 33) while watching their favorite food on the computer screen. Current food craving decreased during a first resting period, increased during paced breathing, and decreased during a second resting period in both conditions. Although current hunger increased in both conditions during paced breathing as well, it remained elevated after the second resting period in the nine breaths condition only. Thus, breathing rate did not influence specific food craving, but slow paced breathing appeared to have a delayed influence on state hunger. Future avenues are suggested for the study of HRV-BF in the context of eating behavior.

An Examination of the “Freshman-15” in Germany

Abstract. The “Freshman-15” refers to an expected average weight gain of 15 pounds during the first year at college in US students. Although an overall weight gain during this period can be observed, most studies found that students gain less than 15 pounds on average. Studies in countries other than the US, however, are scarce. In the current study, 120 female freshmen at a German university were tested at the start of the first semester and again at the start of the second semester (after approximately 6 months). Body mass index (BMI) did not differ between measurements, but participants had 0.2% more body fat at the second measurement. Participants with higher BMI at the first measurement lost weight and participants with higher weight suppression (i.e., the difference between an individual’s highest previous weight and current weight) at the first measurement gained weight. Participants who reported to exercise regularly at the first measurement gained weight, but this effect was driven by those who reduced their amount of physical exercise during the first semester. Dietary habits and eating styles at the first measurement were not associated with weight change. To conclude, no evidence was found for an overall weight gain during the first semester in female, German students. Furthermore, weight change was exclusively predicted by BMI, weight suppression, and regular exercise, while eating behaviors were unrelated to weight change. Thus, it appears that variables influencing energy expenditure are more robust predictors of future weight gain than variables influencing energy intake in female freshmen.

Cardiac autonomic regulation as a predictor for childhood obesity intervention success

Childhood obesity is a major public health concern; behavioural interventions induce weight reduction in some, but success is variable. Heart rate variability (HRV) has been associated with impulse control and extent of dieting success. This study investigated the relationship between HRV and post childhood obesity intervention weight-management success, and involved recording the frequency-domain HRV measures ratio between low frequency and high frequency power (LF/HF) and high frequency power (HF), and the time-domain measure, percentage of successive beat-to-beat intervals that differ by more than 50ms (PNN50). It was expected that greater LF/HF and lower HF would be associated with greater post-intervention weight gain, and that greater PNN50 would be associated with greater impulse control. Seventy-four participants aged 9-14 (M=10.7; s.d.: 1.1) attended a weight-management camp, where HRV was recorded. Stop signal reaction time (SSRT) was also recorded as a measure of impulse control. As expected, SSRT was positively associated with pre-intervention body mass (r=0.301, P=0.010) and negatively associated with PNN50 (β=0.29, P=0.031). Post-intervention body mass change was positively associated with LF/HF (β=0.34, P=0.037), but was not associated with HF. Lifestyle interventions may have a greater chance of effectively supporting long-term weight-management for children with lower LF/HF; assessing HRV of obese children may be helpful in informing obesity treatment decisions.

Dieting and Food Cue-Related Working Memory Performance

Executive functioning (e.g., working memory) is tightly intertwined with self-regulation. For example, food cue-elicited craving has been found to impair working memory performance. Furthermore, current dieters have been found to show lower working memory performance than non-dieters. Recent research, however, suggests that it is crucial to consider dieting success in addition to current dieting status or restrained eating in order to reveal cognitive mechanisms that are associated with successful eating-related self-regulation. The current study investigated food cue-related working memory performance as a function of dieting status and dieting success in female students. Participants performed an n-back task with pictures of food and neutral objects. Reaction time in response to food pictures was slower than in response to neutral pictures, whereas omission errors did not differ between picture types. Current food craving was increased after performing the food block, but not after the neutral block. There was an indirect effect of current dieting status on higher food craving after the food block, which was mediated by slower reaction time to food vs. neutral pictures. Furthermore, higher dieting success was associated with fewer omission errors in the food vs. neutral block in current dieters. There were no relationships of restrained eating with current food craving and task performance. Results further highlight the need to differentiate between successful and unsuccessful dieting in addition to current dieting status or restrained eating when examining possible mechanisms of overeating or successful restraint. Although palatable food cues induce food craving regardless of dieting success, they may boost executive functioning in successful dieters, which helps them to overcome these temptations.

Restrained eating predicts effortful self-control as indicated by heart rate variability during food exposure

When confronted with food, restrained eaters have to inhibit the pursuit of the short-term goal of enjoying their food for the sake of the long-term goal of controlling their weight. Thus, restrained eating creates a self-control situation. In the present study we investigated the initiation of effortful self-control by food cues in accordance with the level of restrained eating. We expected that a preceding act of self-control would moderate the association between restrained eating and effortful self-control initiated by food cues. Participants (N=111) were randomly assigned to a task requiring self-control or a task not requiring self-control. Subsequently, participants were exposed to palatable food, and effortful self-control was measured via heart rate variability (HRV). Restrained eating was associated with enhanced HRV during food exposure after exercising self-control but not after not exercising self-control. The results indicate that maintaining dieting goals results in food cues initiating effortful self-control after a preceding act of self-control. We suggest considering the effect of acts of self-control when modeling the initial steps on the path from food cues to unsuccessful restrained eating.

Food-cue affected motor response inhibition and self-reported dieting success: a pictorial affective shifting task

Behavioral inhibition is one of the basic facets of executive functioning and is closely related to self-regulation. Impulsive reactions, that is, low inhibitory control, have been associated with higher body mass index (BMI), binge eating, and other problem behaviors (e.g., substance abuse, pathological gambling, etc.). Nevertheless, studies which investigated the direct influence of food-cues on behavioral inhibition have been fairly inconsistent. In the current studies, we investigated food-cue affected behavioral inhibition in young women. For this purpose, we used a go/no-go task with pictorial food and neutral stimuli in which stimulus-response mapping is reversed after every other block (affective shifting task). In study 1, hungry participants showed faster reaction times to and omitted fewer food than neutral targets. Low dieting success and higher BMI were associated with behavioral disinhibition in food relative to neutral blocks. In study 2, both hungry and satiated individuals were investigated. Satiation did not influence overall task performance, but modulated associations of task performance with dieting success and self-reported impulsivity. When satiated, increased food craving during the task was associated with low dieting success, possibly indicating a preload-disinhibition effect following food intake. Food-cues elicited automatic action and approach tendencies regardless of dieting success, self-reported impulsivity, or current hunger levels. Yet, associations between dieting success, impulsivity, and behavioral food-cue responses were modulated by hunger and satiation. Future research investigating clinical samples and including other salient non-food stimuli as control category is warranted.

A short version of the Food Cravings Questionnaire-Trait: the FCQ-T-reduced

One of the most often used instruments for the assessment of food cravings is the Food Cravings Questionnaire (FCQ), which consists of a trait (FCQ-T; 39 items) and state (FCQ-S; 15 items) version. Scores on the FCQ-T have been found to be positively associated with eating pathology, body mass index (BMI), low dieting success and increases in state food craving during cognitive tasks involving appealing food stimuli. The current studies evaluated reliability and validity of a reduced version of the FCQ-T consisting of 15 items only (FCQ-T-r). Study 1 was a questionnaire study conducted online among students (N = 323). In study 2, female students (N = 70) performed a working memory task involving food and neutral pictures. Study 1 indicated a one-factorial structure and high internal consistency (α = 0.94) of the FCQ-T-r. Scores of the FCQ-T-r were positively correlated with BMI and negatively correlated with dieting success. In study 2, participants reported higher state food craving after the task compared to before. This increase was positively correlated with the FCQ-T-r. Hours since the last meal positively predicted food craving before the task when controlling for FCQ-T-r scores and the interaction of both variables. Contrarily, FCQ-T-r scores positively predicted food craving after the task when controlling for food deprivation and the interaction term. Thus, trait food craving was specifically associated with state food craving triggered by palatable food-cues, but not with state food craving related to plain hunger. Results indicate high reliability of the FCQ-T-r. Replicating studies that used the long version, small-to-medium correlations with BMI and dieting success could be found. Finally, scores on the FCQ-T-r predicted cue-elicited food craving, providing further support of its validity. The FCQ-T-r constitutes a succinct, valid and reliable self-report measure to efficiently assess experiences of food craving as a trait.

Impulsive reactions to food-cues predict subsequent food craving

Low inhibitory control has been associated with overeating and addictive behaviors. Inhibitory control can modulate cue-elicited craving in social or alcohol-dependent drinkers, and trait impulsivity may also play a role in food-cue reactivity. The current study investigated food-cue affected response inhibition and its relationship to food craving using a stop-signal task with pictures of food and neutral stimuli. Participants responded slower to food pictures as compared to neutral pictures. Reaction times in response to food pictures positively predicted scores on the Food Cravings Questionnaire - State (FCQ-S) after the task and particularly scores on its hunger subscale. Lower inhibitory performance in response to food pictures predicted higher FCQ-S scores and particularly those related to a desire for food and lack of control over consumption. Task performance was unrelated to current dieting or other measures of habitual eating behaviors. Results support models on interactive effects of top-down inhibitory control processes and bottom-up hedonic signals in the self-regulation of eating behavior, such that low inhibitory control specifically in response to appetitive stimuli is associated with increased craving, which may ultimately result in overeating.

Time course of electrocortical food-cue responses during cognitive regulation of craving

In our current obesogenic environment, exposure to visual food-cues can easily lead to craving and overeating because short-term, pleasurable effects of food intake dominate over the anticipated long-term adverse effects such as weight gain and associated health problems. Here we contrasted these two conditions during food-cue presentation while acquiring event-related potentials (ERPs) and subjective craving ratings. Female participants (n = 25) were presented with either high-calorie (HC) or low-calorie (LC) food images under instructions to imagine either immediate (NOW) or long-term effects (LATER) of consumption. On subjective ratings for HC foods, the LATER perspective reduced cravings as compared to the NOW perspective. For LC foods, by contrast, craving increased under the LATER perspective. Early ERPs (occipital N1, 150-200 ms) were sensitive to food type but not to perspective. Late ERPs (late positive potential, LPP, 350-550 ms) were larger in the HC-LATER condition than in all other conditions, possibly indicating that a cognitive focus on negative long-term consequences induced negative arousal. This enhancement for HC-LATER attenuated to the level of the LC conditions during the later slow wave (550-3000 ms), but amplitude in the HC-NOW condition was larger than in all other conditions, possibly due to a delayed appetitive response. Across all conditions, LPP amplitudes were positively correlated with self-reported emotional eating. In sum, results reveal that regulation effects are secondary to an early attentional analysis of food type and dynamically evolve over time. Adopting a long-term perspective on eating might promote a healthier food choice across a range of food types.

Women with elevated food addiction symptoms show accelerated reactions, but no impaired inhibitory control, in response to pictures of high-calorie food-cues

Addictive behaviors are accompanied by a lack of inhibitory control, specifically when individuals are confronted with substance-related cues. Thus, we expected women with symptoms of food addiction to be impaired in inhibitory control, when confronted with palatable, high-calorie food-cues. Female college students (N=50) were divided in low and high food addiction groups based on the symptom count of the Yale Food Addiction Scale. Participants performed a Go/No-go-task with high-calorie food-cues or neutral pictures presented behind the targets. Self-reported impulsivity was also assessed. The high food addiction group had faster reaction times in response to food-cues as compared to neutral cues and reported higher attentional impulsivity than the low food addiction group. Commission and omission errors did not differ between groups or picture types. Hence, women with food addiction symptoms reported higher attentional impulsivity and reacted faster in response to food-cues, although neither increased self-reported motor impulsivity nor impaired behavioral inhibition was found. Food addiction symptoms seem to be related to attentional aspects of impulsivity but not other facets of impulsivity.