Elasticity in portion selection is predicted by severity of anorexia and food type in adolescents

Development of Momentary Appetite Capture (MAC): A versatile tool for monitoring appetite over long periods

Understanding how an intervention impacts appetite in real-life settings and over several days remains a challenging and under-explored research question. To this end, we developed Momentary Appetite Capture (MAC), a form of ecological momentary assessment that combines automated text messaging with an online platform. Participants report their appetite using visual analogue scales (hunger, desire to eat, and fullness) and a virtual portion-size selection task. In two separate studies, we assessed the feasibility and test-retest reliability of MAC. Participants were prompted every 2 hours over a 14-hour window, and they repeated this assessment over two consecutive weekdays. For each participant, we calculated a daily time-averaged area under the curve (AUC) for each appetite measure. In Study One (N = 25) time-averaged AUC was significantly positively correlated across test days for hunger (r = 0.563, p = .003), desire to eat (r = 0.515, p = .008) and prospective portion size (r = 0.914, p < .001), but not for fullness (r = 0.342, p = .094). Participants completed 95% of MACs (380 of 400), and we used participant feedback to improve the MAC tool and study protocol for Study Two. In Study Two (N = 31), 94% of MACs were completed (468 of 496). Across days, time-averaged AUC was significantly positively correlated for hunger (r = 0.595, p = < .001), fullness (r = 0.501, p = .004), desire to eat (r = 0.585, p < .001), and prospective portion size (r = 0.757, p < .001). Together, these studies suggest that MAC could be an acceptable and reliable tool to track appetite throughout the day. In the future, MAC could be used to explore the impact of weight-loss interventions on natural fluctuations in appetite.

Human nutritional intelligence underestimated? Exposing sensitivities to food composition in everyday dietary decisions

The social and cultural significance of food is woven into every aspect of our dietary behaviour, and it contributes to our complex interaction with food. To find order within this complexity scientists often look for dietary 'universals' - phenomena or basic principles that guide our food choice and meal size, irrespective of wider context. One such idea is that taste characteristics provide a signal for dietary composition (e.g., sweet taste signals carbohydrate). Others have suggested that behaviour is guided by learning and is based on associations that form between the flavour of a food and its post-ingestive effects. Despite a large body of research, evidence supporting both processes is equivocal, leading some to conclude that humans are largely indifferent to food composition. Here, we argue that human abilities to gauge the nutritional composition or value of food have been underestimated, and that they can be exposed by embracing alternative methods, including cross-cultural comparisons, large nutrition surveys, and the use of virtual portion-selection tools. Our group has focused on assessments of food choice and expected satiety, and how comparisons across everyday foods can reveal non-linear relationships with food energy density, and even the potential for sensitivity to micronutrient composition. We suggest that these abilities might reflect a complex form of social learning, in which flavour-nutrient associations are not only formed but communicated and amplified across individuals in the form of a cuisine. Thus, rather than disregarding sociocultural influences as extraneous, we might reimagine their role as central to a process that creates and imbues a 'collective dietary wisdom.' In turn, this raises questions about whether rapid dietary, technological, and cultural change disrupts a fundamental process, such that it no longer guarantees a 'nutritional intelligence' that confers benefits for health.

The effects of snack foods of different energy density on self-served portions and consumption in preschool children

It is recommended that preschoolers serve themselves their own food portions; however, it is unclear what factors influence the amount they select for consumption, and particularly how their selected portions are influenced by food properties such as energy density, volume, and weight. We offered preschool children snacks differing in energy density (ED) and investigated the effects on the amounts they served and then consumed. In a crossover design, 52 children aged 4-6 y (46% girls; 21% overweight) ate an afternoon snack on 2 days in their childcare classrooms. Before each snack time, children served the amount they would like to eat of 4 snacks presented in equal volumes but differing in ED (higher-ED: pretzels, cookies; lower-ED: strawberries, carrots). Across the 2 sessions, children were given their self-served amount of either pretzels (3.9 kcal/g) or strawberries (0.3 kcal/g) and intake was measured. Later, children tasted all 4 snacks and rated liking. Results showed that the portions children served themselves were influenced by their liking ratings (p = 0.0006), but after accounting for liking, the volumes they served were similar for all 4 foods (p = 0.27). At snack time, children ate a greater proportion of self-served strawberries (92 ± 4%) than pretzels (73 ± 4%; p = 0.0003), but because of the ED difference they consumed 55 ± 4 kcal more from pretzels than strawberries (p < 0.0001). The difference in snack intake by volume was not attributable to liking ratings (p = 0.87). That children served a consistent volume of similarly-liked snacks suggests that their portions were affected more by visual cues than by weight or energy content. Despite eating a greater volume of lower-ED strawberries, children consumed more energy from the higher-ED pretzels, highlighting the contribution of energy density to children's energy intake.

Children's Portion Selection Is Predicted by Food Liking and Is Related to Intake in Response to Increased Portions

BACKGROUND

When children choose amounts of food to eat, it is unclear what influences the portions they select and whether their selections are related to the amounts they consume.

OBJECTIVES

Using a computer survey, we investigated the effect of food liking on portion selection in middle childhood and examined how children's selections were related to measured intake at meals in which portions of all foods were varied across 4 test days.

METHODS

Fifty-one children aged 7-10 y completed a computer survey of 20 common foods with a range of energy density. For each food, the survey presented sliding scales with 5 images varying in portion size and children indicated their liking and the amount they would eat at a specified meal or snack. On 4 test days in a randomized crossover design, children were served a meal of 6 foods from the survey with portions of 100%, 133%, 167%, or 200% of baseline amounts. Data were analyzed using random coefficients models.

RESULTS

Across the 20 foods used in the survey, portion selection ratings were predicted by food liking ratings (P < 0.0001). After accounting for liking, portion selection ratings did not vary by food energy density (P = 0.50). At the meals, intake of all 6 foods increased when larger portions were served (P = 0.002). Furthermore, the selected portion of a food on the survey was positively related both to intake of that food at the 100%-portion meal (P = 0.014) and to increased intake as larger portions were served (P < 0.0001).

CONCLUSIONS

Children aged 7-10 y were able to use a computer survey to choose food portions that predicted their measured intake in response to increased portions. The relation of liking to selection and intake indicates that to promote children's consumption of larger portions of low-energy-dense foods such as fruits and vegetables, these foods must be well liked by the children. This trial was registered at clinicaltrials.gov as NCT02759523.

Estimation of meal portions in bulimia nervosa compared to anorexia nervosa and healthy controls

PURPOSE

Bulimia nervosa (BN) and anorexia nervosa (AN) are potentially life-threatening eating disorders (ED) that primarily affect young people, mostly women. The central common pathology is linked to the relationship with food and with abnormalities in food intake. A previous study indicated that individuals with AN tend to overestimate food portion sizes compared to healthy controls (HC), but no study has investigated these patterns in BN, which was the objective of this study.

METHODS

Women with BN (27), AN (28), and HC (27) were asked to rate different meal portion sizes in two conditions: as if they were supposed to eat them (intent-to-eat condition) or in general (general condition). BN results were compared to HC and AN using mixed model analyses.

RESULTS

BN showed larger estimations compared to HC, while smaller estimations compared to AN. These differences were found mostly for intermediate portion sizes. No difference for conditions (intent-to-eat; general) was found between groups.

CONCLUSION

When estimating food portion sizes, individuals with BN seem to fall intermediately between HC and AN. ED symptoms in BN were most strongly associated with higher portion estimation. This might therefore reflect one aspect of the cognitive distortions typically seen also in AN. A therapeutic option could include the frequent visual exposure to increasing portions of food, what may serve to recalibrate visual perceptions of what a "normal-sized" portion of food looks like.

LEVEL OF EVIDENCE

Level II: Evidence obtained from well-designed controlled trials without randomization.

Rationale and development of a manualised dietetic intervention for adults undergoing psychological treatment for an eating disorder

PURPOSE

Due to the current dearth of literature regarding dietetic treatment for patients with an eating disorder (ED), no manualised dietetic interventions exist to enable the testing of dietetic treatments in this population. This paper aims to: (1) describe the rationale and development of a manualised dietetic intervention for adults undergoing concurrent psychological treatment for an ED; and (2) provide an overview of the feasibility testing of this intervention.

METHODS

Current best evidence to date for dietetic treatment in EDs was utilised to develop a manualised dietetic intervention for feasibility testing alongside outpatient psychological 'treatment as usual'.

RESULTS

The developed intervention consists of five, dietitian-delivered outpatient sessions: (1) getting started; (2) mechanical eating and dietary rules; (3) estimating portion sizes and social eating; (4) maximising your meal plan and meal preparation; and (5) review and treatment planning as well as pre- and post-intervention assessments.

CONCLUSION

This paper is intended as a resource for clinicians and researchers in the conduct of future studies examining dietetic treatment for patients with an ED.

LEVEL OF EVIDENCE

Level V, description of a new manualised, reproducible dietetic intervention.

Recalled and momentary virtual portions created of snacks predict actual intake under laboratory stress condition

Virtual portion tasks have been used to predict food intake in healthy individuals, severity of illness in individuals with anorexia nervosa, and weight loss in bariatric surgery patients. Whether portion creation in response to a recalled interpersonal stress ("recalled stress portions") could be used as a proxy for ad lib intake, after a stressor, remains untested, and the mechanism supporting this relationship is unclear. The present study's goals were: 1) to validate virtual portion tasks as proxies for actual food intake in a stressful context and 2) to test a causal pathway in which these virtual stress portions predict ad lib intake after stress. We proposed that this relationship is mediated by virtual portions created the moment after laboratory stress or rest manipulation (momentary portions), and before the participant actually ate food. At screening, 29 healthy undergraduate white women created virtual portions of eight snacks (apples, olives, potato chips, pretzels, caramel popcorn, milk chocolate) that they typically eat and also portions they recall eating in response to a stressful interpersonal situation. In addition, after a Trier Social Stress Test, or a rest period, on separate days in counterbalanced order, participants created 'momentary' virtual portions of the same snacks presented during screening, and then were given potato chips, mini golden Oreos, and M&Ms to eat. Recalled stress (b = 0.07 ± 0.02, p = 0.003), and momentary stress (b = 0.12 ± 0.02, p = 0.00001), portions of milk chocolate accounted for 29% and 51%, respectively, of the variance in ad lib stress intake of M&Ms. Typical (b = 0.15 ± 0.07, p = 0.03), and momentary rest (b = 0.21 ± 0.06, p = 0.002), portions of chips accounted for 16% and 31%, respectively, of the variance in ad lib rest intake of chips. The causal pathway from recalled stress portion to ad lib stress snack intake was completely mediated by momentary stress portion for milk chocolate and M&Ms (β = 0.04 ± 0.02, z = 2.4, p = 0.0154). These findings illustrate the planning and recall components of eating in response to stress, but not necessarily under rest conditions. This recalled stress virtual portion paradigm has clinical and research value in that it can detect those who overconsume in response to stress.

Dietetic intervention for adult outpatients with an eating disorder: a systematic review and assessment of evidence quality

CONTEXT

Eating disorders (EDs) are complex mental illnesses that require medical, psychological, and dietetic intervention to assist patients achieve recovery.

OBJECTIVE

Available evidence was reviewed regarding dietetic intervention for adult outpatients with an ED and the quality of this evidence was assessed.

DATA SOURCES

Systematic literature searches were conducted using 5 databases (MEDLINE, PreMEDLINE, EMBASE, CINAHL, PsycINFO) for studies comparing adults with an ED receiving a dietetic intervention with those receiving a psychological intervention alone, those receiving a combined dietetic and psychological intervention, or a control group.

DATA EXTRACTION

Literature searches returned 3078 results, with 10 articles reporting on 9 randomized controlled trials meeting the inclusion criteria. The quality of evidence was assessed using the Cochrane Risk-of-Bias tool and Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework.

DATA ANALYSIS

GRADE assessments for studies involving individuals with anorexia nervosa indicated very low quality of evidence for outcomes including weight, ED psychopathology and ED behaviors , and no studies measured nutritional changes. For studies conducted with participants with bulimia nervosa or binge eating disorder, only 1 study included a group receiving combined evidence-based psychological and dietetic intervention. A combined intervention produced moderate-quality evidence for lower attrition, greater abstinence from ED behaviors, and more meals eaten per week in comparison with a stand-alone psychological or dietetic intervention.

CONCLUSIONS

There is currently limited evidence to sufficiently assess the impact of incorporating dietetic interventions into outpatient treatment for adults with an ED; however, available evidence supports clinical practice guidelines that dietetic intervention should not be delivered as a stand-alone treatment. Additional methodologically sound studies in larger samples are required to fully inform dietetic treatment in EDs and incorporation of such interventions as part of a multidisciplinary treatment approach.

How do patients with eating disorders perceive and evaluate food portion sizes? A systematic review

OBJECTIVE

The selection of adequate portion sizes plays a key role in the nutritional treatment of eating disorders (EDs). There is limited knowledge concerning the estimation of portion sizes in individuals with EDs.

METHOD

We performed a systematic review according to the PRISMA statement to synthesise current evidence in this field. Of N = 584 hits, four full-texts were included in the qualitative synthesis.

RESULTS

While patients with anorexia nervosa (AN) tend to overestimate the size of energy-dense food items and small to medium sized meal portions, they do not show a different estimation compared to healthy controls when judging the amount of food pieces. Large portion sizes were associated with increased anxiety in patients with AN.

DISCUSSION

The overestimation of food portion sizes seems to be driven by attitudinal and/or higher cognitive factors associated with AN. Differences between the studies are discussed and suggestions for future studies are given.

Reliability and responsiveness of virtual portion size creation tasks: Influences of context, foods, and a bariatric surgical procedure

Food portion size influences energy intake and sustained high-energy intake often leads to obesity. Virtual portion creation tasks (VPCTs), in which a participant creates portions of food on a computer screen, predict intake in healthy individuals. The objective of this study was to determine whether portions created in VPCTs are stable over time (test-retest reliability) and responsive to factors known to influence food intake, such as eating contexts and food types, and to determine if virtual portions can predict weight loss. Patients with obesity scheduled for bariatric surgery (n = 29), and individuals with a normal BMI (18.5-24.9 kg/m2, controls, n = 29), were instructed to create virtual portions of eight snack foods, which varied in energy density (low and high) and taste (sweet and salty). Portions were created in response to the following eating situations, or "contexts": What they would a) eat to stay healthy (healthy), b) typically eat (typical), c) eat to feel comfortably satisfied (satisfied), d) consider the most that they could tolerate eating (maximum), and e) eat if nothing was limiting them (desired). Tasks were completed before, and 3 months after, surgery in patients, and at two visits, 3 months apart, in controls. Body weight (kg) was recorded at both visits. Virtual portions differed significantly across groups, visits, eating contexts, energy densities (low vs. high), and tastes (sweet vs. salty). Portions created by controls did not change over time, while portions created by patients decreased significantly after surgery, for all contexts except healthy. For patients, desired and healthy portions predicted 3-month weight loss. VPCTs are replicable, responsive to foods and eating contexts, and predict surgical weight loss. These tasks could be useful for individual assessment of expectations of amounts that are eaten in health and disease and for prediction of weight loss.

Consumo de formulações emagrecedoras e risco de transtornos alimentares em universitários de cursos de saúde

RESUMO Objetivo Avaliar o consumo de formulações emagrecedoras e sua possível associação com o risco de transtornos alimentares (TAs) em universitários de cursos de saúde de diversos níveis socioeconômicos. Métodos Estudo epidemiológico transversal, realizado com 276 universitários matriculados em quatro cursos da área da saúde. Para a obtenção dos dados, utilizaram-se três instrumentos autoaplicáveis: o Eating Attitudes Test (EAT-26), o Bulimic Investigatory Test of Edinburgh (BITE) e, para investigar o consumo de formulações emagrecedoras, um questionário elaborado pela própria equipe de pesquisa. Para análise dos dados, aplicou-se o teste qui-quadrado, adotando-se o nível de significância de 5%. Resultados Vinte e um universitários apresentaram risco de TA pela escala EAT-26, correspondente a 7,6% dos pesquisados. A frequência do uso de formulações emagrecedoras foi de 7,2%. Houve associação significativa (p < 0,001) entre o uso de formulações emagrecedoras e a presença de risco para TA (33,3%), com percentual muito elevado quando comparado ao percentual de entrevistados sem risco de TA que estavam em uso de medicamentos (5,1%). Conclusões O consumo de formulações emagrecedoras esteve associado tanto à presença de risco para TA, nas escalas EAT-26 e BITE, quanto aos níveis socioeconômicos, principalmente para a classe de renda C.

Development of the "Recovery from Eating Disorders for Life" Food Guide (REAL Food Guide) - a food pyramid for adults with an eating disorder

BACKGROUND

There is limited evidence to inform nutrition and dietetic interventions for individuals with eating disorders even though it is recommended as an essential part of multidisciplinary management. There is minimal guidance, an absence of standardised nutrition educational material, and no research on how best to educate patients on healthy eating and how to achieve nutrition adequacy. Therefore the REAL Food Guide was developed.

METHODS

The REAL Food Guide is a pyramid with four layers and key nutrition messages beside each layer that was conceived to address gaps in nutrition education and intervention for individuals with eating disorders. Written and verbal consumer feedback was obtained from consumers receiving treatment regarding the acceptability and usefulness of the REAL Food Guide. A unique database was developed to reflect the types of foods and realistic portion sizes that patients are likely to select. This database was used for nutrition modelling to assess the nutrition adequacy of three meal patterns (meat containing, vegetarian and semi-vegan) for both weight maintenance and weight regain. Each meal pattern was compared to the Nutrient Reference Values for Australia and New Zealand.

RESULTS

Nutritional analysis demonstrated nutritional adequacy of meal patterns for energy, macronutrients and most micronutrients when the recommended number of serves from the REAL Food Guide were assessed. All meal patterns were adequate in micronutrients except for the semi-vegan meal pattern that was inadequate in vitamin D. Feedback from individuals with eating disorders demonstrates the nutrition education tool was acceptable to them as they felt it was more helpful for their recovery than general nutrition guidelines.

CONCLUSION

The REAL Food Guide is a comprehensive and user-friendly guide that clinicians can use to educate patients about components of a balanced and healthy diet. The guide can educate all eating disorder clinicians, including those who are new to the field, about the basics of nutrition. Clinicians using the guide can be confident that, if followed, patient's energy and nutritional requirements will be met and important nutrition education messages are reinforced, that are tailored to the beliefs and concerns of individuals with eating disorders.

Food portion size area mediates energy effects on expected anxiety in anorexia nervosa

A study in which adolescent patients with anorexia nervosa (n = 24) rated their expected food-anxiety in response to images of portions of food (potatoes, rice pizza, and M&Ms) showed that lower energy-dense foods elicited higher expected anxiety per kilocalorie than higher energy-dense foods. However, the area of the portion sizes could be an unmeasured variable driving the anxiety response. To test the hypothesis that area mediates the effects of energy content on expected anxiety, the same images of portions were measured in area (cm2), and standardized values of expected anxiety were regressed from standardized values of energy and area of portions. With regression of expected anxiety from portion size in area, M&Ms, which had the highest energy density of the four foods, elicited the highest expected anxiety slope (β = 1.75), which was significantly different from the expected anxiety slopes of the other three foods (β range = 0.67 - 0.96). Area was confirmed as a mediator of energy effects from loss of significance of the slopes when area was added to the regression of expected anxiety from energy x food. When expected anxiety was regressed from food, area, energy and area by energy interaction, area accounted for 5.7 times more variance than energy, and β for area (0.7) was significantly larger (by 0.52, SE = 0.15, t = 3.4, p = 0.0007) than β for energy (0.19). Area could be a learned cue for the energy content of food portions, and thus, for weight gain potential, which triggers anxiety in patients with anorexia nervosa.

Stress-induced eating in women with binge-eating disorder and obesity

The purpose of the current study was to investigate stress-induced eating in women with binge-eating disorder (BED) and obesity. Three groups of women [obese with BED (n=9); obese non-BED (n=11); and normal weight (NW) non-BED (n=12)], rated their levels of hunger and psychological distress before and after completing the Trier Social Stress Test, followed by food anticipation and then consumption of their preferred snack food. We differentiated between the motivational and hedonic components of eating by measuring the amount of food participants poured into a serving bowl compared to the amount consumed. Stress did not affect poured and consumed calories differently between groups. Across all subjects, calories poured and consumed were positively correlated with post-stress hunger, but calories poured was positively correlated with post-stress anxiety and negative affect. These results indicate that stress-related psychological factors may be more strongly associated with the motivational drive to eat (i.e. amount poured) rather than the hedonic aspects of eating (i.e. amount consumed) for women in general. Exploratory correlation analyses per subgroup suggest that post-stress hunger was positively associated with calories poured and consumed in both non-BED groups. In the obese BED group, calories consumed was negatively associated with dietary restraint and, although not significantly, positively associated with stress-induced changes in anxiety.These findings suggest that stress-induced snacking in obese BED women may be influenced by psychological factors more so than homeostatic hunger mechanisms. After controlling for dietary restraint and negative affect, the NW non-BED women ate a greater percentage of the food they poured than both obese groups, suggesting that obesity may be associated with a heightened motivational drive to eat coupled with a reduction in hedonic pleasure from eating post-stress. Further studies that incorporate novel approaches to measuring the motivational versus hedonic aspects of stress-induced eating may expose nuanced eating behaviors that differentiate BED and obesity. If confirmed, our findings would support prevention and treatment strategies that target subsets of women based on obesity and BED status.