Development and testing of a labeled magnitude scale of perceived satiety

Rationale, Design, and Baseline Characteristics of Participants in the Health@NUS mHealth Augmented Cohort Study Examining Student-to-Work Life Transition: Protocol for a Prospective Cohort Study

BACKGROUND

Integration of mobile health data collection methods into cohort studies enables the collection of intensive longitudinal information, which gives deeper insights into individuals' health and lifestyle behavioral patterns over time, as compared to traditional cohort methods with less frequent data collection. These findings can then fill the gaps that remain in understanding how various lifestyle behaviors interact as students graduate from university and seek employment (student-to-work life transition), where the inability to adapt quickly to a changing environment greatly affects the mental well-being of young adults.

OBJECTIVE

This paper aims to provide an overview of the study methodology and baseline characteristics of participants in Health@NUS, a longitudinal study leveraging mobile health to examine the trajectories of health behaviors, physical health, and well-being, and their diverse determinants, for young adults during the student-to-work life transition.

METHODS

University students were recruited between August 2020 and June 2022 in Singapore. Participants would complete biometric assessments and questionnaires at 3 time points (baseline, 12-, and 24-month follow-up visits) and use a Fitbit smartwatch and smartphone app to continuously collect physical activity, sedentary behavior, sleep, and dietary data over the 2 years. Additionally, up to 12 two-week-long bursts of app-based ecological momentary surveys capturing lifestyle behaviors and well-being would be sent out among the 3 time points.

RESULTS

Interested participants (n=1556) were screened for eligibility, and 776 participants were enrolled in the study between August 2020 and June 2022. Participants were mostly female (441/776, 56.8%), of Chinese ethnicity (741/776, 92%), undergraduate students (759/776, 97.8%), and had a mean BMI of 21.9 (SD 3.3) kg/m2, and a mean age of 22.7 (SD 1.7) years. A substantial proportion were overweight (202/776, 26.1%) or obese (42/776, 5.4%), had indicated poor mental well-being (World Health Organization-5 Well-Being Index ≤50; 291/776, 37.7%), or were at higher risk for psychological distress (Kessler Psychological Distress Scale ≥13; 109/776, 14.1%).

CONCLUSIONS

The findings from this study will provide detailed insights into the determinants and trajectories of health behaviors, health, and well-being during the student-to-work life transition experienced by young adults.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05154227; https://clinicaltrials.gov/study/NCT05154227.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/56749.

Early Dinner Improves the Glycemic Profile in Habitual Late Eaters With Uncontrolled Type 2 Diabetes Mellitus in the Short Term

Background Late dinner (LD) can worsen the glucose profile in type 2 diabetes (T2D). We assessed the short-term effect of early dinner (ED) on glycemic control in habitual late eaters with uncontrolled T2D. Methodology This interventional, single-arm, within-group trial recruited 10 habitual late eaters with uncontrolled T2D (glycosylated hemoglobin: 7-9% and either fasting plasma glucose (FPG): ≥140 mg/dl or post-prandial plasma glucose: ≥200 mg/dl). They had their usual LD (beyond 22:00 hours) on Days 0-3 and ED (before 20:00 hours) on Days 4-10. Continuous glucose monitoring system (CGMS) parameters, two-hour post-dinner, and fasting (10-hour post-dinner) investigations were analyzed. Bedtime hunger was assessed using a Labeled Magnitude Satiety Scale. Results The mean dinner time was reduced from 22:28 hours to 19:29 hours. CGMS revealed that ED lowered the 10-hour post-dinner incremental area under the curve (22,587.9 ± 5,168.3 mg/dl×mins vs. 15,886.3 ± 4,288.7 mg/dl×mins, P < 0.002), 10-hour post-dinner average blood glucose (ABG) (137.5 ± 9.3 mg/dl vs. 125 ± 7.9 mg/dl, P < 0.002), 24-hour ABG (132.2 ± 7.5 mg/dl vs. 124.8 ± 5.4 mg/dl, P = 0.037), and night mean amplitude of glucose excursion (83.7 ± 5.8 mg/dl vs. 69.3 ± 7.5 mg/dl, P = 0.027). ED also reduced FPG (119.8 ± 7.3 mg/dl vs. 105.2 ± 5.7 mg/dl, P = 0.015), fasting insulin (15.0 ± 4.3 µIU/ml vs. 9.7 ± 2.7 µIU/ml, P < 0.002), and HOMA-IR (4.36 ± 1.2 vs. 2.56 ± 0.79, P < 0.002). Post-dinner glucose, insulin, and inflammatory markers were unchanged. Bedtime hunger increased significantly on Days 4 and 5 but returned to baseline by Day 10. Conclusions A simple modification of dinner time in habitual late eaters with uncontrolled T2D improves FPG, glycemic control, and insulin resistance in the short term.

Orthonasal olfactory influences on consumer food behaviour

It is often suggested in the popular press that food chains deliberately introduce enticing product aromas into (and in the immediate vicinity of) their premises in order to attract customers. However, despite the widespread use of odours in the field of sensory marketing, laboratory research suggests that their effectiveness in modulating people's food behaviours depends on a range of contextual factors. Given the evidence that has been published to date, only under a subset of conditions is there likely to be a measurable effect of the presence of ambient odours on people's food attitudes and choices. This narrative historical review summarizes the various ways in which food odours appear to bias people's food preferences (appetite) and food choices (food consumption and purchase). Emphasis is placed on those experimental studies that have been designed to investigate how the characteristics of the olfactory stimuli (e.g., the congruency between the olfactory cues and the foods, intensity and duration of exposure to odours, and taste properties of odours) modulate the effects of olfactory cues on food behaviour. The review also explores the moderating roles of individual differences, such as dietary restraint, Body Mass Index (BMI), genetic and cultural differences in odour sensitivity and perception. Ultimately, following a review of empirical studies on food-related olfaction, current approaches in scent marketing are discussed and a research agenda is proposed to help encourage further studies on the effective application of scents in promoting healthy foods.

Individual differences in late positive potential amplitude and theta power predict cue-induced eating

Cue-induced reward-seeking behaviors are regulated by both the affective and cognitive control systems of the brain. This study aimed at investigating how individual differences in affective and cognitive responses to cues predicting food rewards contribute to the regulation of cue-induced eating. We recorded electroencephalogram (EEG) from 59 adults while they viewed emotional and food-related images that preceded the delivery of food rewards (candies) or non-food objects (beads). We measured the amplitude of the late positive potential (LPP) in response to a variety of motivationally relevant images and power in the theta (4-8 Hz) frequency band after candies or beads were dispensed to the participants. We found that individuals with larger LPP responses to food images than to pleasant images (C>P group) ate significantly more during the experiment than those with the opposite response pattern (P>C group, p < 0.001). Furthermore, we found that individuals with higher theta power after dispensation of the candy than of the bead (θCA>θBE) ate significantly more than those with the opposite response pattern (θBE>θCA, p < 0.001). Finally, we found that the crossed P>C and θBE>θCA group ate less (p < 0.001) than did the other three groups formed by crossing the LPP and theta group assignments, who exhibited similar eating behavior on average (p = 0.662). These findings demonstrate that individual differences in both affective and cognitive responses to reward-related cues underlie vulnerability to cue-induced behaviors, underscoring the need for individualized treatments to mitigate maladaptive behaviors.

The Crick-Eatery: A Novel Approach to Evaluate Cricket (Acheta domesticus) Powder Replacement in Food Products through Product Eating Experience and Emotional Response

This study was conducted to evaluate three different food products containing cricket powder for consumer acceptability, emotional response, satiety, and plate waste. US untrained consumers (n = 108), from the San Luis Obispo, CA area, were recruited to evaluate three food products (sausage, pasta, and brownies) as components in a three-course meal that either contain cricket powder (CP) or not (Control). The CP sausage was found to have lower liking scores than the Control for the attributes tested (p < 0.05). The CP pasta was found to be higher in overall liking than the Control (p < 0.05). The CP Brownies were rated highly across the attributes, except for texture and aftertaste (p < 0.05). Though the CP products were found to be as acceptable as the Controls, the use of cricket powder may have affected the texture and flavor profile of both the CP sausage and brownies. The participants selected more positive emotions terms for both the CP and Control products than negative emotions. Negative terms selected, such as worried, decreased once the products were consumed (p < 0.05). Plate waste and subjective satiety may also be indicators of consumer acceptability. Significant correlations were found between appearance liking and satiety as well as taste liking and plate waste for both the Control and CP products/dishes (p < 0.05). Based on this work, future acceptance of insect-based products may be encouraged by evaluating the products throughout an eating experience.

Valuing the Diversity of Research Methods to Advance Nutrition Science

The ASN Board of Directors appointed the Nutrition Research Task Force to develop a report on scientific methods used in nutrition science to advance discovery, interpretation, and application of knowledge in the field. The genesis of this report was growing concern about the tone of discourse among nutrition professionals and the implications of acrimony on the productive study and translation of nutrition science. Too often, honest differences of opinion are cast as conflicts instead of areas of needed collaboration. Recognition of the value (and limitations) of contributions from well-executed nutrition science derived from the various approaches used in the discipline, as well as appreciation of how their layering will yield the strongest evidence base, will provide a basis for greater productivity and impact. Greater collaborative efforts within the field of nutrition science will require an understanding that each method or approach has a place and function that should be valued and used together to create the nutrition evidence base. Precision nutrition was identified as an important emerging nutrition topic by the preponderance of task force members, and this theme was adopted for the report because it lent itself to integration of many approaches in nutrition science. Although the primary audience for this report is nutrition researchers and other nutrition professionals, a secondary aim is to develop a document useful for the various audiences that translate nutrition research, including journalists, clinicians, and policymakers. The intent is to promote accurate, transparent, verifiable evidence-based communication about nutrition science. This will facilitate reasoned interpretation and application of emerging findings and, thereby, improve understanding and trust in nutrition science and appropriate characterization, development, and adoption of recommendations.

Efficacy of medicinal cannabis for appetite-related symptoms in people with cancer: A systematic review

BACKGROUND

Anorexia (loss of appetite) is a prevalent and distressing symptom in people with cancer, with limited effective interventions. Medicinal cannabis has shown promise in improving appetite-related symptoms in people with cancer.

AIM

To assess the efficacy of medicinal cannabis for improving appetite-related symptoms in people with cancer, considering measures and outcomes, interventions and toxicity.

DESIGN

Systematic review with narrative approach to synthesis and meta-analysis.

DATA SOURCES

Databases (MEDLINE, CINAHL, CENTRAL), websites and trials registries were searched from inception to February 2021. Included studies were randomised controlled trials (RCT) in English peer-reviewed journals comparing medicinal cannabis with placebo and/or another intervention. Study quality was assessed using the Cochrane risk of bias tool.

RESULTS

Five studies were included that compared medicinal cannabis interventions (dronabinol, nabilone and cannabis extract) either with placebo (n = 4) or megestrol acetate (n = 1). Measures and trial endpoints varied, but efficacy was demonstrated in one trial only, in which dronabinol significantly improved chemosensory perception and other secondary outcomes (taste of food, premeal appetite, proportion of calories consumed as protein) compared with placebo. Cannabis interventions were generally well tolerated across studies, regardless of the product or dose, although the comprehensive measurement of toxicities was limited.

CONCLUSION

Evidence from RCTs that medicinal cannabis increases appetite in people with cancer is limited. Measures, outcomes and interventions were variable, and toxicities have not been comprehensively evaluated. Future research should carefully consider biological mechanisms to guide more nuanced selection of endpoints and interventions, including product, dose and administration.

Elucidating the role of the gut microbiota in the physiological effects of dietary fiber

BACKGROUND

Dietary fiber is an integral part of a healthy diet, but questions remain about the mechanisms that underlie effects and the causal contributions of the gut microbiota. Here, we performed a 6-week exploratory trial in adults with excess weight (BMI: 25-35 kg/m2) to compare the effects of a high-dose (females: 25 g/day; males: 35 g/day) supplement of fermentable corn bran arabinoxylan (AX; n = 15) with that of microbiota-non-accessible microcrystalline cellulose (MCC; n = 16). Obesity-related surrogate endpoints and biomarkers of host-microbiome interactions implicated in the pathophysiology of obesity (trimethylamine N-oxide, gut hormones, cytokines, and measures of intestinal barrier integrity) were assessed. We then determined whether clinical outcomes could be predicted by fecal microbiota features or mechanistic biomarkers.

RESULTS

AX enhanced satiety after a meal and decreased homeostatic model assessment of insulin resistance (HOMA-IR), while MCC reduced tumor necrosis factor-α and fecal calprotectin. Machine learning models determined that effects on satiety could be predicted by fecal bacterial taxa that utilized AX, as identified by bioorthogonal non-canonical amino acid tagging. Reductions in HOMA-IR and calprotectin were associated with shifts in fecal bile acids, but correlations were negative, suggesting that the benefits of fiber may not be mediated by their effects on bile acid pools. Biomarkers of host-microbiome interactions often linked to bacterial metabolites derived from fiber fermentation (short-chain fatty acids) were not affected by AX supplementation when compared to non-accessible MCC.

CONCLUSION

This study demonstrates the efficacy of purified dietary fibers when used as supplements and suggests that satietogenic effects of AX may be linked to bacterial taxa that ferment the fiber or utilize breakdown products. Other effects are likely microbiome independent. The findings provide a basis for fiber-type specific therapeutic applications and their personalization.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT02322112 , registered on July 3, 2015. Video Abstract.

Validity and Feasibility of the Monitoring and Modeling Family Eating Dynamics System to Automatically Detect In-field Family Eating Behavior: Observational Study

Background

The field of dietary assessment has a long history, marked by both controversies and advances. Emerging technologies may be a potential solution to address the limitations of self-report dietary assessment methods. The Monitoring and Modeling Family Eating Dynamics (M2FED) study uses wrist-worn smartwatches to automatically detect real-time eating activity in the field. The ecological momentary assessment (EMA) methodology was also used to confirm whether eating occurred (ie, ground truth) and to measure other contextual information, including positive and negative affect, hunger, satiety, mindful eating, and social context.

Objective

This study aims to report on participant compliance (feasibility) to the 2 distinct EMA protocols of the M2FED study (hourly time-triggered and eating event–triggered assessments) and on the performance (validity) of the smartwatch algorithm in automatically detecting eating events in a family-based study.

Methods

In all, 20 families (58 participants) participated in the 2-week, observational, M2FED study. All participants wore a smartwatch on their dominant hand and responded to time-triggered and eating event–triggered mobile questionnaires via EMA while at home. Compliance to EMA was calculated overall, for hourly time-triggered mobile questionnaires, and for eating event–triggered mobile questionnaires. The predictors of compliance were determined using a logistic regression model. The number of true and false positive eating events was calculated, as well as the precision of the smartwatch algorithm. The Mann-Whitney U test, Kruskal-Wallis test, and Spearman rank correlation were used to determine whether there were differences in the detection of eating events by participant age, gender, family role, and height.

Results

The overall compliance rate across the 20 deployments was 89.26% (3723/4171) for all EMAs, 89.7% (3328/3710) for time-triggered EMAs, and 85.7% (395/461) for eating event–triggered EMAs. Time of day (afternoon odds ratio [OR] 0.60, 95% CI 0.42-0.85; evening OR 0.53, 95% CI 0.38-0.74) and whether other family members had also answered an EMA (OR 2.07, 95% CI 1.66-2.58) were significant predictors of compliance to time-triggered EMAs. Weekend status (OR 2.40, 95% CI 1.25-4.91) and deployment day (OR 0.92, 95% CI 0.86-0.97) were significant predictors of compliance to eating event–triggered EMAs. Participants confirmed that 76.5% (302/395) of the detected events were true eating events (ie, true positives), and the precision was 0.77. The proportion of correctly detected eating events did not significantly differ by participant age, gender, family role, or height (P>.05).

Conclusions

This study demonstrates that EMA is a feasible tool to collect ground-truth eating activity and thus evaluate the performance of wearable sensors in the field. The combination of a wrist-worn smartwatch to automatically detect eating and a mobile device to capture ground-truth eating activity offers key advantages for the user and makes mobile health technologies more accessible to nonengineering behavioral researchers.

Comparison of a Standardized High-Fat Meal versus a High-Fat Meal Scaled to Body Mass for Measuring Postprandial Triglycerides: A Randomized Crossover Study

Post-meal triglycerides are an independent cardiovascular disease (CVD) risk factor, but the ideal high-fat meal formulation has yet to be standardized and is one challenge prohibiting widespread clinical adoption of postprandial triglyceride assessment. Two general approaches often used are giving individuals a high-fat meal scaled to body weight or a standardized high-fat meal containing a set fat bolus. A recent expert panel statement has endorsed the latter, specifying 75 g of fat as an appropriate fat dosage. Despite this recommendation, no study to date has tested whether there is a difference in postprandial triglycerides or if risk classification is affected based on these different approaches. We recruited 16 generally healthy individuals with roughly equal distribution among body mass index (BMI)class (n = 5–6/per BMI category) and sex (n = 2–3 M/F) within each BMI class. Each participant underwent two abbreviated fat tolerance tests separated by ~1 week: one with a scaled to body weight high-fat meal (9 kcal/kg; 70% fat) and a standardized meal containing 75 g of fat (70% fat). Fasting, 4 h, and absolute change in triglycerides across the entire sample and within each BMI category were similar regardless of high-fat meal. Only one participant with obesity had discordant postprandial responses between the fat tolerance tests (i.e., different CVD risk classification). These findings suggest that, within a certain range of fat intake, generally healthy individuals will have a similar postprandial triglyceride response. Considering the greater convenience of utilizing standardized high-fat meals, our data suggest that a standardized high-fat meal may be acceptable for large-scale studies and clinical implementation.

Resistant starch wheat increases PYY and decreases GIP but has no effect on self-reported perceptions of satiety

Dietary fiber has numerous health benefits, such as increasing satiety, and is regularly included in healthy dietary recommendations. However, different types and sources of fiber vary in their chemical properties and biological effects. This double-blind, randomized, placebo-controlled, crossover study investigated the effects of resistant starch type 2 (RS2) from wheat on self-reported perceptions of satiety and associated gut hormones in 30 healthy adults ages 40-65 years of age. Participants consumed rolls made using either RS2-enriched wheat flour or a wild-type flour for one week before a test day during which they ate a mixed meal containing the same roll type. Both self-reported perceptions of satiety and plasma concentrations of gut hormones were measured following the meal to assess whether the RS2-enriched wheat enhanced satiety and suppressed hunger for a longer period than the control wheat. Exploratory analysis indicated that fasting and peak concentration of peptide YY_3-36 (PYY_3-36; q_fast = 0.02, q_peak = 0.02) increased, while peak concentration and iAUC of glucose-dependent insulinotropic peptide (GIP; q_peak < 0.001, q_iAUC < 0.001) decreased after ingesting RS2-enriched wheat. However, self-reported perceptions of hunger or fullness using visual analog scales (VAS) did not differ following the test meal.

Efficacy of metformin and fermentable fiber combination therapy in adolescents with severe obesity and insulin resistance: study protocol for a double-blind randomized controlled trial

Background

Accumulating evidence suggests that the metabolic effects of metformin and fermentable fibers are mediated, in part, through diverging or overlapping effects on the composition and metabolic functions of the gut microbiome. Pre-clinical animal models have established that the addition of fiber to metformin monotherapy improves glucose tolerance. However, possible synergistic effects of combination therapy (metformin plus fiber) have not been investigated in humans. Moreover, the underlying mechanisms of synergy have yet to be elucidated. The aim of this study is to compare in adolescents with obesity the metabolic effects of metformin and fermentable fibers in combination with those of metformin or fiber alone. We will also determine if therapeutic responses correlate with compositional and functional features of the gut microbiome.

Methods

This is a parallel three-armed, double-blinded, randomized controlled trial. Adolescents (aged 12–18 years) with obesity, insulin resistance (IR), and a family history of type 2 diabetes mellitus (T2DM) will receive either metformin (850 mg p.o. twice/day), fermentable fibers (35 g/day), or a combination of metformin plus fiber for 12 months. Participants will be seen at baseline, 3, 6, and 12 months, with a phone follow-up at 1 and 9 months. Primary and secondary outcomes will be assessed at baseline, 6, and 12 months. The primary outcome is change in IR estimated by homeostatic model assessment of IR; key secondary outcomes include changes in the Matsuda index, oral disposition index, body mass index z-score, and fat mass to fat-free mass ratio. To gain mechanistic insight, endpoints that reflect host-microbiota interactions will also be assessed: obesity-related immune, metabolic, and satiety markers; humoral metabolites; and fecal microbiota composition, short-chain fatty acids, and bile acids.

Discussion

This study will compare the potential metabolic benefits of fiber with those of metformin in adolescents with obesity, determine if metformin and fiber act synergistically to improve IR, and elucidate whether the metabolic benefits of metformin and fiber associate with changes in fecal microbiota composition and the output of health-related metabolites. This study will provide insight into the potential role of the gut microbiome as a target for enhancing the therapeutic efficacy of emerging treatments for T2DM prevention.

Trial registration

ClinicalTrials.gov NCT04578652. Registered on 8 October 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05060-8.

Glucose metabolism responds to perceived sugar intake more than actual sugar intake

The authors examine study participants who have Type 2 diabetes to determine whether cognition affects glucose levels in contrast to widely held suppositions. Thirty participants who have type 2 diabetes consume beverages that have identical ingredients but have deceptive nutrition facts labels. Blood glucose levels measured four times before and after beverage consumption show that blood glucose levels increase when participants believe the beverage has high sugar content as portrayed on the labels. Also, individual eating behaviors and nutritional satisfaction are linked to changes in blood glucose levels. The study results support the concept of anticipatory budgeting on glucose metabolism. The findings provide pressing evidence for the psychobiological model of chronic disease, suggesting that psychological intervention programs may be important for diabetes management, beyond current programs in which type 2 diabetes is managed through diet, exercise, and medications only.

High-Fat Breakfast Meal Replacement in Overweight and Obesity: Implications on Body Composition, Metabolic Markers, and Satiety

The purpose of this paper was to determine the effect of replacing breakfast with a high-fat drink on fat mass (FM), lean mass (LM), percent body fat (%BF), visceral fat (VAT), resting metabolic rate (RMR), fuel utilization (RER), blood lipids and satiety in overweight and obese adults. Healthy adults (n = 42; 21 Females; body mass index (BMI): 32.8 ± 4.6 kg·m-2) were randomized to control (CON; n = 21) or meal replacement (MRP; n = 22) groups. Body composition was measured using a four-compartment model; RMR and RER were assessed from indirect calorimetry. The MRP (70% fat) was consumed once daily for eight weeks. For males, there was no change (p > 0.05) in FM (mean difference (MD) = 0.41 ± 1.19 kg], %BF MD = 0.50 ± 1.09%, LM MD = -0.64 ± 1.79 kg, or VAT MD = -0.31 ± 1.36 cm for MRP versus CON. Similarly, no differences for females for FM MD = -0.73 ± 1.37 kg, %BF MD = -0.57 ± 1.26%, LM MD = 0.31 ± 1.37 kg, or VAT MD: -0.83 ± 1.2 cm. HDL was significantly reduced in the MRP group for females (adjusted mean change: -6.41 ± 4.44 units, p = 0.018). There was no effect on RMR or RER. Satiety increased in the afternoon for MRP (p = 0.021). Despite high fat, no negative impact on lipids resulted; increased satiety may be beneficial for controlling afternoon cravings, but does not affect body composition.

The reality of "food porn": Larger brain responses to food-related cues than to erotic images predict cue-induced eating

While some individuals can defy the lure of temptation, many others find appetizing food irresistible. The goal of this study was to investigate the neuropsychological mechanisms that increase individuals' vulnerability to cue-induced eating. Using ERPs, a direct measure of brain activity, we showed that individuals with larger late positive potentials in response to food-related cues than to erotic images are more susceptible to cue-induced eating and, in the presence of a palatable food option, eat more than twice as much as individuals with the opposite brain reactivity profile. By highlighting the presence of individual brain reactivity profiles associated with susceptibility to cue-induced eating, these findings contribute to the understanding of the neurobiological basis of vulnerability to obesity.

Between- and Within-Subjects Predictors of the Kilocalorie Content of Bites of Food

BACKGROUND

This study builds on previous research that seeks to estimate kilocalorie intake through microstructural analysis of eating behaviors. As opposed to previous methods, which used a static, individual-based measure of kilocalories per bite, the new method incorporates time- and food-varying predictors. A measure of kilocalories per bite (KPB) was estimated using between- and within-subjects variables.

OBJECTIVE

The purpose of this study was to examine the relationship between within-subjects and between-subjects predictors and KPB, and to develop a model of KPB that improves over previous models of KPB. Within-subjects predictors included time since last bite, food item enjoyment, premeal satiety, and time in meal. Between-subjects predictors included body mass index, mouth volume, and sex.

PARTICIPANTS/SETTING

Seventy-two participants (39 female) consumed two random meals out of five possible meal options with known weights and energy densities. There were 4,051 usable bites measured.

MAIN OUTCOME MEASURES

The outcome measure of the first analysis was KPB. The outcome measure of the second analysis was meal-level kilocalorie intake, with true intake compared to three estimation methods.

STATISTICAL ANALYSES PERFORMED

Multilevel modeling was used to analyze the influence of the seven predictors of KPB. The accuracy of the model was compared to previous methods of estimating KPB using a repeated-measured analysis of variance.

RESULTS

All hypothesized relationships were significant, with slopes in the expected direction, except for body mass index and time in meal. In addition, the new model (with nonsignificant predictors removed) improved over earlier models of KPB.

CONCLUSIONS

This model offers a new direction for methods of inexpensive, accurate, and objective estimates of kilocalorie intake from bite-based measures.

Effects of Self-Conditioning Techniques (Self-Hypnosis) in Promoting Weight Loss in Patients with Severe Obesity: A Randomized Controlled Trial

OBJECTIVE

The usefulness of the rapid-induction techniques of hypnosis as an adjunctive weight-loss treatment has not been defined. This randomized controlled trial evaluated whether self-conditioning techniques (self-hypnosis) added to lifestyle interventions contributed to weight loss (primary outcome), changes in metabolic and inflammatory variables, and quality of life (QoL) improvement (secondary outcomes) in severe obesity.

METHODS

Individuals (with BMI = 35-50 kg/m² ) without organic or psychiatric comorbidity were randomly assigned to the intervention (n = 60) or control arm (n = 60). All received exercise and behavioral recommendations and individualized diets. The intervention consisted of three hypnosis sessions, during which self-hypnosis was taught to increase self-control before eating. Diet, exercise, satiety, QoL, anthropometric measurements, and blood variables were collected and measured at enrollment and at 1 year (trial end).

RESULTS

A similar weight loss was observed in the intervention (-6.5 kg) and control (-5.6 kg) arms (β = -0.45; 95% CI: -3.78 to 2.88; P = 0.79). However, habitual hypnosis users lost more weight (-9.6 kg; β = -10.2; 95% CI: -14.2 to -6.18; P < 0.001) and greatly reduced their caloric intake (-682.5 kcal; β = -643.6; 95% CI: -1064.0 to -223.2; P = 0.005) in linear regression models. At trial end, the intervention arm showed lower C-reactive protein values (β = -2.55; 95% CI: -3.80 to -1.31; P < 0.001), higher satiety (β = 19.2; 95% CI: 7.71-30.6; P = 0.001), and better QoL (β = 0.09; 95% CI: 0.02-0.16; P = 0.01).

CONCLUSIONS

Self-hypnosis was not associated with differences in weight change but was associated with improved satiety, QoL, and inflammation. Indeed, habitual hypnosis users showed a greater weight loss.

Breakfast food health and acute exercise: Effects on state body image

Food intake and exercise have been shown to alter body satisfaction in a state-dependent manner. One-time consumption of food perceived as unhealthy can be detrimental to body satisfaction, whereas an acute bout of moderate-intensity aerobic exercise can be beneficial. The current study examined the effect of exercise on state body image and appearance-related self-esteem following consumption of isocaloric foods perceived as healthy or unhealthy in 36 female college students (18-30 years old) in the Northeastern United States. Using a randomized-controlled design, participants attended six study sessions with breakfast conditions (healthy, unhealthy, no food) and activity (exercise, quiet rest) as within-participants factors. Body image questionnaires were completed prior to breakfast condition, between breakfast and activity conditions, and following activity condition. Results showed that consumption of an unhealthy breakfast decreased appearance self-esteem and increased body size perception, whereas consumption of a healthy breakfast did not influence appearance self-esteem but increased body size perception. Exercise did not influence state body image attitudes or perceptions following meal consumption. Study findings suggest that morning meal type, but not aerobic exercise, influence body satisfaction in college-aged females.

The effect of a portion size intervention on French fries consumption, plate waste, satiety and compensatory caloric intake: an on-campus restaurant experiment

Background

One of the driving factors of dietary overconsumption throughout the last decennia is the increase of food portion sizes. Larger portions induce higher daily energy intake, so reducing portion size may reduce intake of excess calories. However, real-life studies about the effects of portion size reduction are lacking. Therefore, this study examined the effect of a French fries portion size reduction on French fries consumption, French fries plate waste, satiety and caloric intake during the subsequent afternoon among university students and employees in a Belgian on-campus restaurant setting. Moreover, this study evaluated consumers’ perception about the portion size reduction.

Methods

The study took place over a two-time (i.e. baseline and intervention week) 4-day period (Tuesday–Friday) in the on-campus restaurant where ±1200 meals are served every day. French fries’ portions were reduced by 20% by replacing the usual porcelain bowl served during the baseline week (±200 g) with smaller volume paper bags during the intervention week (±159 g) in a pre-post real-life experiment. French fries consumption and plate waste were measured in 2056 consumers at baseline and 2175 consumers at intervention. Additionally, interviews were conducted directly after lunch and again between 4 and 6 p.m. on the same day to assess satiety and caloric intake at pre and post in a small subsample of both French fries consumers (n = 19) and non-French fries consumers (n = 14). Post-intervention, the same subsample was interviewed about their perception of the portion size reduction (n = 28).

Results

Total French fries intake decreased by 9.1%, and total plate waste decreased by 66.4%. No differences were found in satiety or caloric intake between baseline and intervention week among the French fries’ consumers. The majority (n = 24, 86%) of French fries consumers noticed the reduction in portion size during the intervention. Although most participants (n = 19, 68%) perceived the reduced portion size as sufficient, only a minority of participants (n = 9, 32%) indicated post-intervention that they would agree with a permanent implementation.

Conclusions

Reducing portion size may lead to reduced caloric intake, without changing perceived levels of satiety.

Physiological and psychological effects of testosterone during severe energy deficit and recovery: A study protocol for a randomized, placebo-controlled trial for Optimizing Performance for Soldiers (OPS)

BACKGROUND

The physiological consequences of severe energy deficit include hypogonadism and the loss of fat-free mass. Prolonged energy deficit also impacts physical performance, mood, attentiveness, and decision-making capabilities. This study will determine whether maintaining a eugonadal state during severe, sustained energy deficit attenuates physiological decrements and maintains mental performance. This study will also assess the effects of normalizing testosterone levels during severe energy deficit and recovery on gut health and appetite regulation.

METHODS

Fifty physically active men will participate in a 3-phase, randomized, placebo-controlled study. After completing a 14-d, energy-adequate, diet acclimation phase (protein: 1.6g∙kg^-1∙d^-1; fat: 30% total energy intake), participants will be randomized to undergo a 28-d, 55% energy deficit phase with (DEF+TEST: 200mg testosterone enanthate per week) or without (DEF) exogenous testosterone. Diet and physical activity will be rigorously controlled. Recovery from the energy deficit (ad libitum diet, no testosterone) will be assessed until body mass has been recovered within ±2.5% of initial body mass. Body composition, stable isotope methodologies, proteomics, muscle biopsies, whole-room calorimetry, molecular biology, activity/sleep monitoring, personality and cognitive function assessments, functional MRI, and comprehensive biochemistries will be used to assess physiological and psychological responses to energy restriction and recovery feeding while volunteers are in an expected hypogonadal versus eugonadal state.

DISCUSSION

The Optimizing Performance for Soldiers (OPS) study aims to determine whether preventing hypogonadism will mitigate declines in physical and mental function that typically occur during prolonged energy deficit, and the efficacy of testosterone replacement on recovery from severe underfeeding.

TRIAL REGISTRATION

NCT02734238.

The acute impact of the intake of four types of bread on satiety and blood concentrations of glucose, insulin, free fatty acids, triglyceride and acylated ghrelin. A randomized controlled cross-over trial

The purpose of the present study is to compare the effects of four different breads (one commercial par-baked wheat bread, three sourdough breads prepared with commercial wheat flour, organic wheat flour, organic einkorn flour) in 16 healthy subjects. The primary outcome of this randomized cross-over trial was evaluating intra-individual changes in glycemic areas-under-the-curve (AUCs) after 50g carbohydrate portions of each bread; secondary outcomes were changes in insulin, fatty free acids (FFA), triglyceride, acylated ghrelin and satiety AUCs. Blood samples and satiety ratings were collected every 30-min for 2-h after the consumption of each bread. The einkorn flour showed the lowest amylase activity, the commercial flour the highest; commercial bread had the highest carbohydrate content and the lowest dietary fiber content. Glucose AUCs were significantly lower after the consumption of sourdough breads made with organic (12,754±1433mg/dL×h) and einkorn flour (12,216±1210mg/dL×h), with respect to the commercial bread (13,849±2193mg/dL×h). Insulin AUCs decreased after the consumption of all sourdough breads when compared to commercial bread. FFA and triglyceride AUCs did not differ by kind of breads. Median ghrelin AUC was significantly lower and satiety higher after the einkorn bread (3710pg/mL×h; 3225±2414, respectively) than after commercial bread consumption (4140pg/mL×h; 1706±1766, respectively), but not with other sourdough breads. In conclusion, the use of sourdough may improve the nutritional features of breads; einkorn bread induced the least disturbance in carbohydrate homeostasis and the greater satiety. If confirmed by further research, these results might have implications in the approach towards chronic dysmetabolic diseases.

Distinct breakfast patterns on satiety perception in individuals with weight excess

OBJECTIVES

Western dietary pattern predisposes to weight gain, insulin resistance and cardiometabolic diseases. Promoting satiety via modifications in diet composition could be useful to fight weight gain. Mediterranean diet which is recognized to be cardioprotective contains high fiber and unsaturated fat contents. We compared the effects of distinct breakfast patterns on satiety of individuals at cardiometabolic risk, and examined the correlation of satiety level after each breakfast intervention period with glucose parameters.

MATERIALS AND METHODS

In this 10-week cross-over clinical trial, 54 individuals with weight excess were submitted to 2 types of 4-week isocaloric breakfasts (2-week washout), one typically Brazilian and a modified one, differing concerning fiber and types of fatty acids contents. Clinical data were collected before and after each breakfast. A satiety scale was applied at fasting and 10, 30 and 120' after breakfast consumption. Repeated measures ANOVA, Student t test or non-parametric correspondents were used; correlations were tested by Pearson or Spearman coefficients.

RESULTS

Anthropometric variations after breakfasts were not significant. Only after the modified breakfast, reduction in blood pressure levels was observed. The satiety level did not show significant variation across each period or between the breakfasts. Non-significant correlation between satiety and glucose, insulin and HOMA-IR values after each intervention period was observed.

CONCLUSION

We conclude that different breakfast compositions do not alter satiety level, which is not correlated to glucose parameters in overweight individuals. Stronger modifications of daily meals might be necessary to differentiate satiety levels under distinct dietary patterns.

Acute aerobic exercise increases implicit approach motivation for dessert images

We examined the effect of acute exercise compared to a cognitive task on implicit approach/avoidance motivation to dessert food images using the Dessert–Approach–Avoidance Task. Participants randomized to exercise had a greater increase in approach motivation to dessert images compared to those completing cognitive tasks ( p=0.046), adjusting for disordered eating, task difficulty, and changes in negative affect. This study provides the first evidence for the use of the Dessert–Approach–Avoidance Task to evaluate the effects of acute exercise on implicit motivations for dessert images. Future studies should examine implicit response to food images using the Dessert–Approach–Avoidance Task in response to chronic exercise.

Blood sugar level follows perceived time rather than actual time in people with type 2 diabetes

The current study investigates whether perceived time has an effect on blood glucose level in people with type 2 diabetes. The hypothesis is that perceived time will have a greater influence over blood glucose level than actual time. Changes in blood glucose levels were measured in 46 participants with diabetes while they completed simple tasks during a 90-min period. Participants' perception of time was manipulated by having them refer to clocks that were either accurate or altered to run fast or slow. Blood glucose levels changed in accordance with how much time they believed had passed instead of how much time had actually passed. These results are an example of the influence psychological processes can directly exert on the body.

Impact of short-term refeeding on appetite and meal experiences in new onset adolescent eating disorders

Restrictive eating disorders (ED) are increasing and represent a serious risk to the health of adolescent females. Restrictive ED in youth are often treated through aggressive short-term refeeding. Although evidence supports that this intervention is the "gold standard" for improving ED outcomes in youth, little research has specifically probed appetite and meal-related responses to this type of intensive, short-term refeeding in newly diagnosed individuals. Information about appetite and meal-related dysfunction could provide valuable insights regarding treatment-interfering features of ED in both acute inpatient and longer-term outpatient treatment. The purpose of this study was to evaluate the hunger, fullness, olfactory, and gustatory responses of adolescents with newly-diagnosed restrictive ED and to probe how and when these responses are altered by refeeding. Using a quasi-experimental ecologically valid methodology, this study described and compared profiles of hunger, fullness, olfactory, and gustatory responses in adolescent females (n = 15) with newly diagnosed restrictive ED at hospital admission (i.e., severe malnutrition) and after medical refeeding, in comparison to healthy controls (n = 15). Results showed that newly diagnosed (i.e., malnourished) adolescents with ED showed significantly different meal-related experiences than controls. Refeeding improved some of these differences, but not all. Following refeeding, females with ED continued to show lower hunger, greater fullness, and lower pleasantness of smell ratings compared to controls. Unpleasantness of taste ratings maladaptively increased, such that females who were re-fed reported more aversive scents than pre-treatment. Profiles of meal-related responses were also identified and compared between groups. The applicability of these findings are discussed within the context of critical periods of change during refeeding treatment and potentially promising intervention targets that might enhance treatment outcomes for adolescents with newly onset, restrictive ED.

Altered metabolic homeostasis is associated with appetite regulation during and following 48-h of severe energy deprivation in adults

BACKGROUND

Military personnel frequently endure intermittent periods of severe energy deficit which can compromise health and performance. Physiologic factors contributing to underconsumption, and the subsequent drive to overeat, are not fully characterized. This study aimed to identify associations between appetite, metabolic homeostasis and endocrine responses during and following severe, short-term energy deprivation.

METHODS

Twenty-three young adults (17M/6F, 21±3years, BMI 25±3kg/m(2)) participated in a randomized, controlled, crossover trial. During separate 48-h periods, participants increased habitual energy expenditure by 1647±345kcal/d (mean±SD) through prescribed exercise at 40-65% VO2peak, and consumed provided isovolumetric diets designed to maintain energy balance at the elevated energy expenditure (EB; 36±93kcal/d energy deficit) or to produce a severe energy deficit (ED; 3681±716kcal/d energy deficit). Appetite, markers of metabolic homeostasis and endocrine mediators of appetite and substrate availability were periodically measured. Ad libitum energy intake was measured over 36h following both experimental periods.

RESULTS

Appetite increased during ED and was greater than during EB despite maintenance of diet volume (P=0.004). Ad libitum energy intake was 907kcal/36h [95% CI: 321, 1493kcal/36h, P=0.004] higher following ED compared to following EB. Serum beta-hydroxybutyrate, free fatty acids, branched-chain amino acids, dehydroepiandrosterone-sulfate (DHEA-S) and cortisol concentrations were higher (P<0.001 for all), whereas whole-body protein balance was more negative (P<0.001), and serum glucose, insulin, and leptin concentrations were lower (P<0.001 for all) during ED relative to during EB. Cortisol concentrations, but not any other hormone or metabolic substrate, were inversely associated with satiety during EB (R(2)=0.23, P=0.04). In contrast, serum glucose and DHEA-S concentrations were inversely associated with satiety during ED (R(2)=0.68, P<0.001). No associations between physiologic variables measured during EB and ad libitum energy intake following EB were observed. However, serum leptin and net protein balance measured during ED were inversely associated with ad libitum energy intake following ED (R(2)=0.48, P=0.01).

CONCLUSION

These findings suggest that changes in metabolic homeostasis during energy deprivation modulate appetite independent of reductions in diet volume. Following energy deprivation, physiologic signals of adipose and lean tissue loss may drive restoration of energy balance.

CLINICAL TRIALS REGISTRATION

www.clinicaltrials.gov #NCT01603550.

Dietary fiber and satiety: the effects of oats on satiety

This review examines the effect of β-glucan, the viscous soluble fiber in oats, on satiety. A literature search for studies that examined delivery of the fiber in whole foods or as an extract was conducted. Viscosity interferes with the peristaltic mixing process in the small intestine to impede digestion and absorption of nutrients, which precipitates satiety signals. From measurements of the physicochemical and rheological properties of β-glucan, it appears that viscosity plays a key role in modulating satiety. However, the lack of standardized methods to measure viscosity and the inherent nature of appetite make it difficult to pinpoint the reasons for inconsistent results of the effects of oats on satiety. Nevertheless, the majority of the evidence suggests that oat β-glucan has a positive effect on perceptions of satiety.

Effects of short-term oral corticosteroid intake on dietary intake, body weight and body composition in adults with asthma - a randomized controlled trial

BACKGROUND

Oral corticosteroids (OCS) are an efficacious treatment for asthma exacerbations, yet risk of adverse effects may decrease patient adherence to therapy. In particular, changes in appetite and dietary intake, which lead to weight gain and changes in body composition, are considered undesirable.

OBJECTIVE

To determine whether 10-day OCS therapy in adults with asthma causes changes in leptin, appetite, dietary intake, body weight and body composition.

METHODS

Double-blinded, placebo-controlled randomized cross-over trial of 10 days prednisolone (50 mg) in adults with stable asthma (n = 55) (ACTRN12611000562976). Pre- and post-assessment included spirometry, body weight, body composition measured by dual-energy X-ray absorptiometry and bioelectrical impedance analysis, appetite measured using a validated visual analogue scale (VAS) and dietary intake assessed using 4-day food records. Leptin was measured as a biomarker of appetite and eosinophils as an adherence biomarker. Outcomes were analysed by generalized linear mixed models.

RESULTS

Subject adherence was confirmed by a significant decrease in blood eosinophils (× 10(9) /L) following prednisolone compared to placebo [Coef. -0.29, 95% CI: (-0.39, -0.19) P < 0.001]. There was no difference in serum leptin (ng/mL) [Coef. 0.13, 95% CI: (-3.47, 3.72) P = 0.945] or appetite measured by VAS (mm) [Coef. -4.93, 95% CI: (-13.64, 3.79) P = 0.267] following prednisolone vs. placebo. There was no difference in dietary intake (kJ/day) [Coef. 255, 95% CI: (-380, 891) P = 0.431], body weight (kg) [Coef. -0.38, 95% CI: (-0.81, 0.05) P = 0.083] or body fat (%) [Coef. -0.31, 95% CI: (-0.81, 0.20) P = 0.230]. Symptoms including sleep and gastrointestinal disturbance were reported significantly more often during prednisolone vs. placebo.

CONCLUSIONS AND CLINICAL RELEVANCE

Short-term OCS in stable asthma did not induce significant changes in appetite, dietary intake, body weight or composition, although other adverse effects may require medical management. This evidence may assist in increasing medication adherence of asthmatics prescribed OCS for exacerbations.

Heterogeneity in brain reactivity to pleasant and food cues: evidence of sign-tracking in humans

Aberrant brain reward responses to food-related cues are an implied characteristic of human obesity; yet, findings are inconsistent. To explain these inconsistencies, we aimed to uncover endophenotypes associated with heterogeneity in attributing incentive salience to food cues in the context of other emotionally salient cues; a phenomenon described as sign- vs goal tracking in preclinical models. Data from 64 lean and 88 obese adults who were 35.5 ± 9.4 years old and predominantly women (79%) were analyzed. Participants viewed food-related, pleasant, neutral and unpleasant images while recording electroencephalograph. Late positive potentials were used to assess incentive salience attributed to the visual stimuli. Eating and affective traits were also assessed. Findings demonstrated that obese individuals, in general, do not demonstrate aberrant brain reward responses to food-related cues. As hypothesized, latent profile analysis of the late positive potential uncovered two distinct groups. 'Sign-trackers' showed greater responses to food-related cues (P < 0.001) but lower responses to pleasant stimuli (P < 0.001) compared with 'goal-trackers'. There were proportionally more obese than lean 'sign-trackers' (P = 0.03). Obese 'sign-trackers' reported significantly higher levels of emotional eating and food craving (P < 0.001). By examining the heterogeneity in brain reactivity to various emotional stimuli, this translational study highlights the need to consider important neurobehavioral endophenotypes of obesity.

The apéritif effect: Alcohol's effects on the brain's response to food aromas in women

OBJECTIVE

Consuming alcohol prior to a meal (an apéritif) increases food consumption. This greater food consumption may result from increased activity in brain regions that mediate reward and regulate feeding behavior. Using functional magnetic resonance imaging, we evaluated the blood oxygenation level dependent (BOLD) response to the food aromas of either roast beef or Italian meat sauce following pharmacokinetically controlled intravenous infusion of alcohol.

METHODS

BOLD activation to food aromas in non-obese women (n = 35) was evaluated once during intravenous infusion of 6% v/v EtOH, clamped at a steady-state breath alcohol concentration of 50 mg%, and once during infusion of saline using matching pump rates. Ad libitum intake of roast beef with noodles or Italian meat sauce with pasta following imaging was recorded.

RESULTS

BOLD activation to food relative to non-food odors in the hypothalamic area was increased during alcohol pre-load when compared to saline. Food consumption was significantly greater, and levels of ghrelin were reduced, following alcohol.

CONCLUSIONS

An alcohol pre-load increased food consumption and potentiated differences between food and non-food BOLD responses in the region of the hypothalamus. The hypothalamus may mediate the interplay of alcohol and responses to food cues, thus playing a role in the apéritif phenomenon.

Impact of bread making on fructan chain integrity and effect of fructan enriched breads on breath hydrogen, satiety, energy intake, PYY and ghrelin

Recently, there has been considerable interest in the satiety inducing properties of inulin type fructans (ITF) as a tool for weight management. As a staple food, breads provide an excellent vehicle for ITF supplementation however the integrity of the ITF chains and properties upon bread making need to be assessed. Breads enriched with 12% fructooligosaccharides (FOS) and 12% inulin were baked and the degree of polymerisation of fructans extracted from the breads were compared to those of pure compounds. An acute feeding study with a single blind cross-over design was conducted with 11 participants to investigate the effect of ITF enriched breads on breath hydrogen, self-reported satiety levels, active ghrelin, total PYY and energy intake. Size exclusion chromatography indicated that little or no depolymerisation of inulin occurred during bread making, however, there was evidence of modest FOS depolymerisation. Additionally, ITF enriched breads resulted in increased concentrations of exhaled hydrogen although statistical significance was reached only for the inulin enriched bread (p = 0.001). There were no significant differences between bread types in reported satiety (p = 0.129), plasma active ghrelin (p = 0.684), plasma PYY (p = 0.793) and energy intake (p = 0.240). These preliminary results indicate that inulin enriched bread may be a suitable staple food to increase ITF intake. Longer intervention trials are required to assess the impact of inulin enriched breads on energy intake and body weight.

Acute Effects of a Spinach Extract Rich in Thylakoids on Satiety: A Randomized Controlled Crossover Trial

Objective: By retarding fat digestion, thylakoids, the internal photosynthetic membrane system of green plants, promote the release of satiety hormones. This study examined the effect of consuming a single dose of concentrated extract of thylakoids from spinach on satiety, food intake, lipids, and glucose compared to a placebo.

Design: Sixty overweight and obese individuals enrolled in a double-blind randomized crossover study consumed the spinach extract or placebo in random order at least a week apart. Blood was drawn for assessments of lipids and glucose before a standard breakfast meal, followed 4 hours later by a 5 g dose of the extract and a standard lunch. Visual analog scales were administered before lunch and at intervals until an ad libitum pizza dinner served 4 hours later. Two hours after lunch a second blood draw was conducted. Mixed models were used to analyze response changes.

Results: Compared to placebo, consuming the spinach extract reduced hunger (p < 0.01) and longing for food over 2 hours (p < 0.01) and increased postprandial plasma glucose concentrations (p < 0.01). There were no differences in plasma lipids and energy intake at dinner, but males showed a trend toward decreased energy intake (p = 0.08).

Conclusions: At this dose, the spinach extract containing thylakoids increases satiety over a 2-hour period compared to a placebo. Thylakoid consumption may influence gender-specific food cravings.

Low-residue breakfast during the preparation for colonoscopy using a polyethylene glycol electrolyte solution: a randomised non-inferiority trial

Goals

To test the hypothesis that the use of a low-residue breakfast (LRB) the day prior to colonoscopy was not inferior to consuming clear fluids alone (CFD) in patients undergoing outpatient colonoscopy with a polyethylene glycol (PEG) bowel preparation.

Background

Optimal colon cleansing is essential for complete visualisation of the mucosa during colonoscopy. Few studies have examined the effect of diet on the quality of bowel cleansing or tolerance in patients using a PEG bowel preparation for colonoscopy.

Methods

Randomised, single-blinded non-inferiority trial. Adult patients scheduled for outpatient colonoscopy with PEG solution were randomised to an LRB followed by clear fluids or CFD using either a traditional or split-dose PEG solution for bowel preparation. The primary outcome was colon cleansing based on the Ottawa Bowel Preparation Score (OBPS).

Results

On an intention-to-treat (ITT) basis, a total of 109 and 105 patients were included in the CFD and LRB arms, respectively, with 116 and 98 patients, respectively, for the per-protocol (PP) analysis. Although there was no difference in the mean total OBPS between the CFD or LRB arms in either the ITT or PP analysis, the threshold for non-inferiority was not met. Patient acceptance of the regimens was higher in the LRB arm than in the CFD arm in the ITT and PP analyses.

Conclusions

This study failed to show the non-inferiority of an LRB in patients receiving bowel preparation with a PEG-based solution. A CFD should be prescribed when using a PEG bowel preparation.

Trial registration number

This trial is registered at ClinicalTrials.gov (NCT01454388).

Ventral frontal satiation-mediated responses to food aromas in obese and normal-weight women

BACKGROUND

Sensory properties of foods promote and guide consumption in hunger states, whereas satiation should dampen the sensory activation of ingestive behaviors. Such activation may be disordered in obese individuals.

OBJECTIVE

Using functional magnetic resonance imaging (fMRI), we studied regional brain responses to food odor stimulation in the sated state in obese and normal-weight individuals targeting ventral frontal regions known to be involved in coding for stimulus reward value.

DESIGN

Forty-eight women (25 normal weight; 23 obese) participated in a 2-day (fed compared with fasting) fMRI study while smelling odors of 2 foods and an inedible, nonfood object. Analyses were conducted to permit an examination of both general and sensory-specific satiation (satiation effects specific to a given food).

RESULTS

Normal-weight subjects showed significant blood oxygen level-dependent responses in the ventromedial prefrontal cortex (vmPFC) to food aromas compared with responses induced by the odor of an inedible object. Normal-weight subjects also showed general (but not sensory-specific) satiation effects in both the vmPFC and orbitofrontal cortex. Obese subjects showed no differential response to the aromas of food and the inedible object when fasting. Within- and between-group differences in satiation were driven largely by changes in the response to the odor of the inedible stimulus. Responses to food aromas in the obese correlated with trait negative urgency, the tendency toward negative affect-provoked impulsivity.

CONCLUSIONS

Ventral frontal signaling of reward value may be disordered in obesity, with negative urgency heightening responses to food aromas. The observed nature of responses to food and nonfood stimuli suggests that future research should independently quantify each to fully understand brain reward signaling in obesity.

Effect of two dietary fibers on satiety and glycemic parameters: a randomized, double-blind, placebo-controlled, exploratory study

BACKGROUND

Dietary carbohydrates may affect metabolic and physiologic parameters. The present study evaluated whether a combination of two dietary fibers, oligofructose (OFS) and pectin (P), altered satiety and glycemic parameters. The primary objective of this study was to determine whether dietary supplementation for 3 weeks with OFS + P would produce a greater reduction in energy intake of an ad libitum test meal compared to control.

METHODS

This was a single center, randomized, double-blind, placebo-controlled, parallel group study in overweight and obese, otherwise healthy, subjects (N = 96). There were two OFS + P treatment groups: high-dose (30 g/d), low-dose (15 g/d), and a control group (maltodextrin 15 g/d). Energy intake, appetite measures based on Satiety Labeled Intensity Magnitude (SLIM) scale, fasting and post-prandial glucose, and insulin levels and body weight were measured at baseline and at the end of 3 weeks. Adverse events and gastrointestinal tolerability of the treatments were also assessed.

RESULTS

An analysis of covariance (ANCOVA) performed on the primary endpoint change from baseline in energy intake, showed no statistically significant difference in energy intake among the three treatment groups (p = 0.5387). The LS mean changes (SE) in energy intake from baseline to week 3 were -58.3 (42.4) kilocalories (kcal) for the high dose group, -74.2 (43.6) kcal for the low dose group, and -9.0 (42.9) kcal for the control group. For the pairwise comparisons of OFS + P doses and control, confidence intervals were constructed around the difference in LS mean changes. All study products were generally well tolerated.

CONCLUSION

There was a directional benefit in ad libitum energy intake for both OFS + P doses compared to control, with a greater reduction in kilocalories in the low dose comparison, but the reductions were not significant. Further studies are warranted.

CLINICAL TRIAL REGISTRATION

GSK Clinical Study Register # W7781293.

Comparison of the metabolic responses to ingestion of hydrothermally processed high-amylopectin content maize, uncooked maize starch or dextrose in healthy individuals

Optimal carbohydrate ingestion strategies as nutritional therapy for glycogen storage diseases have not been fully realised, in part, due to difficulties in accessing patient cohorts, alongside limited details on metabolic effects and insight into working mechanisms. The present pilot study compared glycaemic and fuel oxidation responses following the ingestion of a hydrothermally processed maize starch (HPMS), an uncooked maize starch (UCMS) and maize-derived dextrose (DEX) at rest and during and after exercise in healthy individuals. A total of eight participants (seven males and one female; body mass (BM) 76.9 (SEM 5.2) kg) visited the laboratory on three occasions. During each visit, the participants ingested 1 g/kg BM of HPMS (Glycosade™), UCMS (Argo™) or DEX as a 10% solution. Blood samples were collected over a 2 h rest period and for 2 h after a 60 min treadmill run at 65 (SEM 1) % VO(2max). Mean values with their standard errors were analysed using repeated-measures ANOVA. Blood glucose concentrations under the HPMS condition were significantly elevated from resting values at 90 min (P=0.02) after ingestion compared with those under the UCMS (60 min; P=0.02) and DEX (30 min; P=0.001) conditions. The rate of carbohydrate use during exercise after the ingestion of HPMS was 7-9% lower compared with that after the ingestion of either DEX or UCMS (P<0.05). The total amount of lipids oxidised during exercise was greater under the HPMS condition (26.2 (SEM 2.8) g) compared with that oxidised under the UCMS (19.6 (SEM 2.7) g; P=0.04) or DEX (20.6 (SEM 3.6) g; P=0.07) condition. The results demonstrated a glycaemic advantage to the ingestion of HPMS over that of UCMS or DEX. Carbohydrate oxidation was reduced after the ingestion of HPMS compared with that after the ingestion of UCMS or DEX, with a corresponding higher rate of endogenous lipid use during exercise.

A low-residue breakfast improves patient tolerance without impacting quality of low-volume colon cleansing prior to colonoscopy: a randomized trial

OBJECTIVES

We compared the efficacy and patient tolerance of two dietary regimens used as an adjunct to standard bowel cleansing in preparation for elective colonoscopy.

METHODS

Our prospective, randomized, single-blind, controlled, noninferiority trial compared two dietary regimens administered the day before colonoscopy. Subjects received low-volume bowel preparation. The primary outcome was efficacy of colon cleansing, rated by the Ottawa bowel preparation scale (OBPS). Patient acceptance of the assigned dietary regimen was assessed as a secondary outcome.

RESULTS

The mean OBPS score for the standard clear-fluid diet group was 4.47, compared with 4.62 for the low-residue breakfast group, meeting criteria for noninferiority. The groups reported similar mean intensity of hunger on a visual analog hunger scale. However, overall satisfaction was higher with the low-residue diet than with the clear-fluid diet.

CONCLUSIONS

A low-residue breakfast on the day before elective colonoscopy does not compromise the overall quality of bowel preparation as compared with a standard clear-fluid diet and is likely to be preferred by patients.

Get in my belly: food preferences trigger approach and avoidant postural asymmetries

Appetitive motivational states are fundamental neural and behavioral mechanisms underlying healthy and abnormal eating behavior, though their dynamic influence on food-related behavior is unknown. The present study examined whether personal food-related preferences would activate approach and avoidance systems, modulating spontaneous postural sway toward and away from food items. Participants stood on a balance board that collected real-time data regarding postural sway along two axes (x, y) while they viewed a series of images depicting food items varying in nutritional value and individual preferences. Overall, participants showed reliable postural sway toward highly preferred and away from highly non-preferred items. This effect became more pronounced over time; sway along the mediolateral axis showed no reliable variation by preference. Results carry implications for two-factor (homeostatic versus hedonic) neurobehavioral theories of hunger and appetitive motivation, and carry applied clinical implications for the measurement and management of abnormal eating behavior.

Behavior believability in virtual worlds: agents acting when they need to

Believability has been a perennial goal for the intelligent virtual agent community. One important aspect of believability largely consists in demonstrating autonomous behavior, consistent with the agent's personality and motivational state, as well as the world conditions. Autonomy, on behalf of the agent, implies the existence of an internal structure and mechanism that allows the agent to have its own needs and interests, based on which the agent will dynamically select and generate goals that will in turn lead to self-determined behavior. Intrinsic motivation allows the agent to function and demonstrate behavior, even when no external stimulus is present, due to the constant change of its internal emotional and physiological state. The concept of motivation has already been investigated by research works on intelligent agents, trying to achieve autonomy. The current work presents an architecture and model to represent and manage internal driving factors in intelligent virtual agents, using the concept of motivations. Based on Maslow and Alderfer's bio-psychological needs theories, we present a motivational approach to represent human needs and produce emergent behavior through motivation synthesis. Particular attention is given to basic, physiological level needs, which are the basis of behavior and can produce tendency to action even when there is no other interaction with the environment.