Children with lower ratings of executive functions have a greater response to the portion size effect

Deficits in executive functions (EFs), a set of cognitive processes related to self-regulation, are associated with the development of obesity. Prior studies from our group showed that lower food-cue related activation in brain regions implicated in self-regulation was related to a larger portion size effect. We tested the hypothesis that lower EFs in children would be positively related to the portion size effect. Healthy weight children aged 7-8 y (n = 88), who varied by maternal obesity status, participated in a prospective study. At baseline, the parent primarily in charge of feeding completed the Behavior Rating Inventory of Executive Function (BRIEF2) to assess child EFs, including Behavioral (BRI), Emotional (ERI), and Cognitive (CRI) indices. At 4 baseline sessions, children consumed meals in which the portion sizes of foods (pasta, chicken nuggets, broccoli, and grapes) varied by visit (total meal weight of 769, 1011, 1256, or 1492g). Intake increased with increasing portions in a linear trajectory (p < 0.001). EFs moderated the portion size effect such that lower BRI (p = 0.003) and ERI (p = 0.006) were associated with steeper increases in intake as portions increased. As amount of food increased, children in the lowest functioning tertiles for BRI and ERI increased intake by 35% and 36%, respectively, compared to children in the higher tertiles. Increases in intake among children with lower EFs were for higher- but not lower-energy-dense foods. Thus, in healthy weight children who varied by obesity risk, lower parentally reported EFs were associated with a larger portion size effect, and these results were independent of child and parent weight status. Therefore, EFs may be target behaviors that could be strengthened to help children moderate excess intake in response to large portions of energy-dense foods.

Adding more portion-size options to a menu: A means to nudge consumers to choose larger portions of healthy food items

We propose and find that the extremeness aversion bias when choosing portion-sizes is stronger for healthy food as compared to unhealthy food items. In two studies (and a follow-up) we find that adding an extra-large option to a standard menu of small, medium, and large portions increases the choice share of the larger portion-sizes; but more so for healthy food than for unhealthy food. Furthermore, we find evidence for the lay belief that larger portions of healthy food do not have incremental health costs. When health costs of the larger portions of healthy food were made salient by providing calorie information, the above effects disappeared. These findings show (1) a boundary condition to the extremeness aversion effect when choosing portion sizes, and (2) imply that this bias can act as a nudge to increase the consumption of healthy food.

How Do French Parents Determine Portion Sizes for Their Pre-Schooler? A Qualitative Exploration of the Parent-Child Division of Responsibility and Influencing Factors

Large portion sizes can make children overeat, alter their self-regulation abilities and induce weight gain. However, little is known about how parents determine portion sizes for their children. Using semi-structured interviews with 5 fathers and 32 mothers of pre-schoolers, this study examined French parents' food portioning practices. The division of responsibility between parent and child in deciding portion sizes was explored, as well as the influencing factors and possible sources of information. Parents described a wide range of practices. For most, determining portion sizes is an intuitive action that depends on habits and mainly arises from experiences with feeding their child and his/her appetitive traits. Few parents grant autonomy to their child for portioning and serving food, especially for the first serving. Many influencing factors were identified, including child-related (e.g., appetite, food preferences), parent-related (e.g., avoiding food waste), and external factors (e.g., influence of siblings, French food culture). Most parents do not search for information/recommendations to guide their practices. Stimulating optimal self-regulation of eating in children is important and parents can play a crucial role in this. This study identified barriers and facilitators to guide parents in providing appropriate portion sizes and help include children in this decision process.

The Role of Dishware Size in the Perception of Portion Size in Children and Adolescents with Obesity

Purpose: The influence of dishware on portion size perception in children and adolescents is inconclusive. This study investigated how children and adolescents with both obesity and a normal weight perceived portion size in different sized and shaped dishware items. Methods: The study included 60 children and adolescents with overweight and obesity (OBE) and 27 children and adolescents with normal weight (NW) aged from 9 to 17 years. The participants estimated quantities in three pairs of drinking glasses, one pair of bowls and two pairs of plates which varied in size and shape. The children were instructed to state intuitively which portion they would choose for big or small thirst/hunger. Thereafter they were asked to determine the exact amount by answering which dishware item contained the larger/smaller portion (cognitive evaluation). Results: There were no substantial differences in the intuitive evaluation of portion sizes between OBE and NW. During the cognitive evaluation, OBE estimated the amount of water in the glasses more correctly compared to NW (61% vs. 43%; p = 0.008); OBE estimated the amount of lentils in the bowls and on the plates significantly less correctly (39%) compared to NW (56%; p = 0.013). Conclusions: Habit formation and environmental stimuli might play a greater role in estimating food amounts in dishware than the child’s and adolescent’s body weight.

Impact of Portion Control Tools on Portion Size Awareness, Choice and Intake: Systematic Review and Meta-Analysis

Portion control utensils and reduced size tableware amongst other tools, have the potential to guide portion size intake but their effectiveness remains controversial. This review evaluated the breadth and effectiveness of existing portion control tools on learning/awareness of appropriate portion sizes (PS), PS choice, and PS consumption. Additional outcomes were energy intake and weight loss. Published records between 2006–2020 (n = 1241) were identified from PubMed and WoS, and 36 publications comparing the impact of portion control tools on awareness (n = 7 studies), selection/choice (n = 14), intake plus related measures (n = 21) and weight status (n = 9) were analyzed. Non-tableware tools included cooking utensils, educational aids and computerized applications. Tableware included mostly reduced-size and portion control/calibrated crockery/cutlery. Overall, 55% of studies reported a significant impact of using a tool (typically smaller bowl, fork or glass; or calibrated plate). A meta-analysis of 28 articles confirmed an overall effect of tool on food intake (d = –0.22; 95%CI: –0.38, –0.06; 21 comparisons), mostly driven by combinations of reduced-size bowls and spoons decreasing serving sizes (d = –0.48; 95%CI: –0.72, –0.24; 8 comparisons) and consumed amounts/energy (d = –0.22; 95%CI: –0.39, –0.05, 9 comparisons), but not by reduced-size plates (d = –0.03; 95%CI: –0.12, 0.06, 7 comparisons). Portion control tools marginally induced weight loss (d = –0.20; 95%CI: –0.37, –0.03; 9 comparisons), especially driven by calibrated tableware. No impact was detected on PS awareness; however, few studies quantified this outcome. Specific portion control tools may be helpful as potentially effective instruments for inclusion as part of weight loss interventions. Reduced size plates per se may not be as effective as previously suggested.

Reductions to main meal portion sizes reduce daily energy intake regardless of perceived normality of portion size: a 5 day cross-over laboratory experiment

BACKGROUND

Smaller portions may help to reduce energy intake. However, there may be a limit to the magnitude of the portion size reduction that can be made before consumers respond by increasing intake of other food immediately or at later meals. We tested the theoretical prediction that reductions to portion size would result in a significant reduction to daily energy intake when the resulting portion was visually perceived as 'normal' in size, but that a reduction resulting in a 'smaller than normal' portion size would cause immediate or later additional eating.

METHODS

Over three 5-day periods, daily energy intake was measured in a controlled laboratory study using a randomized crossover design (N = 30). The served portion size of the main meal component of lunch and dinner was manipulated in three conditions: 'large-normal' (747 kcal), 'small-normal' (543 kcal), and 'smaller than normal' (339 kcal). Perceived 'normality' of portion sizes was determined by two pilot studies. Ad libitum daily energy intake from all meals and snacks was measured.

RESULTS

Daily energy intake in the 'large-normal' condition was 2543 kcals. Daily energy intake was significantly lower in the 'small-normal' portion size condition (mean difference - 95 kcal/d, 95% CI [- 184, - 6], p = .04); and was also significantly lower in the 'smaller than normal' than the 'small-normal' condition (mean difference - 210 kcal/d, 95% CI [- 309, - 111], p < .001). Contrary to predictions, there was no evidence that the degree of additional food consumption observed was greater when portions were reduced past the point of appearing normal in size.

CONCLUSIONS

Reductions to the portion size of main-meal foods resulted in significant decreases in daily energy intake. Additional food consumption did not offset this effect, even when portions were reduced to the point that they were no longer perceived as being normal in size.

TRIAL REGISTRATION

Prospectively registered protocol and analysis plan: https://osf.io/natws/; retrospectively registered: https://clinicaltrials.gov/ct2/show/NCT03811210.

Determinants of Portion Size in Children and Adolescents: Insights from the UK National Diet and Nutrition Survey Rolling Programme (2008-2016)

Large portion sizes have been identified as contributing to overweight and obesity, particularly in children and adolescents. This study examined predictors of portion sizes of high energy snack foods eaten by children aged 1.5–18 years. Specifically, we examined whether portion sizes were adjusted for age, and what external features of the environment might be linked to large portion sizes. Portion sizes were derived from four-day food diaries that form the UK National Diet and Nutrition Survey. Diaries from 5942 children were examined and multilevel models were used to discover whether age, gender, location, time of day, household income, and watching TV while eating predicted portion sizes of savoury snacks, chocolate, confectionery and biscuits. Portion sizes of all the target foods were predicted by age. Boys had larger portions, and portion sizes were larger when target foods were consumed later in the day. Portion sizes were larger outside the home, for example in leisure venues, but the target foods were eaten more frequently in the home. As dietary patterns change to include more snack intake outside the home, these locations could be an important space to target for interventions for portion control.

Increasing the proportion of healthier foods available with and without reducing portion sizes and energy purchased in worksite cafeterias: protocol for a stepped-wedge randomised controlled trial

BACKGROUND

Overconsumption of energy from food contributes to high rates of overweight and obesity in many populations. A promising set of interventions tested in pilot studies in worksite cafeterias, suggests energy intake may be reduced by increasing the proportion of healthier - i.e. lower energy - food options available, and decreasing portion sizes. The current study aims to assess the impact on energy purchased of i. increasing the proportion of lower energy options available; ii. combining this with reducing portion sizes, in a full trial.

METHODS

A stepped-wedge randomised controlled trial in 19 worksite cafeterias, where the proportion of lower energy options available in targeted food categories (including main meals, snacks, and cold drinks) will be increased; and combined with reduced portion sizes. The primary outcome is total energy (kcal) purchased from targeted food categories using a pooled estimate across all sites. Follow-up analyses will test whether the impact on energy purchased varies according to the extent of intervention implementation.

DISCUSSION

This study will provide the most reliable estimate to date of the effect sizes of two promising interventions for reducing energy purchased in worksite cafeterias.

TRIAL REGISTRATION

The study was prospectively registered on ISRCTN (date: 24.05.19; TRN: ISRCTN87225572; doi: https://doi.org/10.1186/ISRCTN87225572).

Portion size effects vary: The size of food units is a bigger problem than the number

While it is well-known that larger food portions lead to increased consumption (i.e., the portion size effect), previous studies confound the effect of the size and the number of food units making up the larger portion. Moreover, empirical tests of the mechanism underlying the portions size effect are scarce. In response to these shortcomings, we present three experiments that test the impact of food unit-size and unit-number on consumption of increasingly large portion sizes, and assess whether perceptions of quantity (driven by unit size or number) mediate the portion size effect. Study 1 (n = 185), tracking actual consumption, shows that the portion size effect is determined more by unit-size than unit-number. Relative consumption ratios are higher when participants were served portions made up of enlarged food units compared to more food units. Since perceived quantity and consumption are thought to be negatively related, Study 2 (n = 193) reveals that consumers' quantity perceptions of portions are lower for unit-size (vs. unit-number) increases. Study 3 (n = 189) considers both perceived quantity and consumption and demonstrates that perceived quantity indeed mediates the effect of food portion size on consumption. Finally, this study also shows that encouraging consumers to focus perceptually on size when portion size increases are in terms of unit-size, or focus on number when portion size increases are in terms of unit-number, supports them in increasing quantity perceptions and decreasing actual consumption. Hence, manipulating the perceptual focus of consumers helps to mitigate the portion size effect. The findings contribute to literature on the portion size effect and numerosity heuristic, and provide practical insights on food packaging so to tackle the obesity crisis.

Big hearts, small hands: a focus group study exploring parental food portion behaviours

BACKGROUND

The development of healthy food portion sizes among families is deemed critical to childhood weight management; yet little is known about the interacting factors influencing parents' portion control behaviours. This study aimed to use two synergistic theoretical models of behaviour: the COM-B model (Capability, Opportunity, Motivation - Behaviour) and Theoretical Domains Framework (TDF) to identify a broad spectrum of theoretically derived influences on parents' portion control behaviours including examination of affective and habitual influences often excluded from prevailing theories of behaviour change.

METHODS

Six focus groups exploring family weight management comprised of one with caseworkers (n = 4), four with parents of overweight children (n = 14) and one with parents of healthy weight children (n = 8). A thematic analysis was performed across the dataset where the TDF/COM-B were used as coding frameworks.

RESULTS

To achieve the target behaviour, the behavioural analysis revealed the need for eliciting change in all three COM-B domains and nine associated TDF domains. Findings suggest parents' internal processes such as their emotional responses, habits and beliefs, along with social influences from partners and grandparents, and environmental influences relating to items such as household objects, interact to influence portion size behaviours within the home environment.

CONCLUSION

This is the first study underpinned by COM-B/TDF frameworks applied to childhood weight management and provides new targets for intervention development and the opportunity for future research to explore the mediating and moderating effects of these variables on one another.

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.

Does the incorporation of portion-control strategies in a behavioral program improve weight loss in a 1-year randomized controlled trial?

BACKGROUND/OBJECTIVES

Controlling food portion sizes can help reduce energy intake, but the effect of different portion-control methods on weight management is not known. In a 1-year randomized trial, we tested whether the efficacy of a behavioral weight-loss program was improved by incorporating either of the two portion-control strategies instead of standard advice about eating less.

SUBJECTS/METHODS

The Portion-Control Strategies Trial included 186 women with obesity (81%) or overweight (19%). Participants were randomly assigned to one of three equally intensive behavioral programs, consisting of 19 individual sessions over 12 months. The Standard Advice Group was instructed to eat less food while making healthy choices, the Portion Selection Group was instructed to choose portions based on the energy density using tools such as food scales and the Pre-portioned Foods Group was instructed to structure meals around pre-portioned foods such as single-serving main dishes, for which some vouchers were provided. In an intention-to-treat analysis, a mixed-effects model compared weight loss trajectories across 23 measurements; at month 12, weight was measured for 151 participants (81%).

RESULTS

The trajectories showed that the Pre-portioned Foods Group initially lost weight at a greater rate than the other two groups (P=0.021), but subsequently regained weight at a greater rate (P=0.0005). As a result, weight loss did not differ significantly across groups at month 6 (mean±s.e. 5.2±0.4 kg) or month 12 (4.5±0.5 kg). After 1 year, measured weight loss averaged 6% of baseline weight. The frequency of using portion-control strategies initially differed across groups, then declined over time and converged at months 6 and 12.

CONCLUSIONS

Incorporating instruction on portion-control strategies within a 1-year behavioral program did not lead to a greater weight loss than standard advice. Using pre-portioned foods enhanced early weight loss, but this was not sustained over time. Long-term maintenance of behavioral strategies to manage portions remains a challenge.

Restrained Eating and Food Cues: Recent Findings and Conclusions

PURPOSE OF REVIEW

The purposes of the present review are to organize the recent literature on the effects of food cues on restrained and unrestrained eaters and to determine current directions in such work.

RECENT FINDINGS

Research over the last several years involves both replicating the work showing that restrained eaters respond to attractive food cues by eating more but unrestrained eaters show less responsiveness and extending this work to examine the mechanisms that might underlie this differential responsiveness. Labeling a food as healthy encourages more eating by restrained eaters, while diet-priming cues seem to curtail their consumption even in the face of attractive food cues. Work on cognitive responses indicates that restrained (but not unrestrained) eaters have both attention and memory biases toward food cues. Restrained eaters attend more strongly to food- and diet-related cues than do unrestrained eaters, as evidenced in both their eating behavior and their attention and memory responses to such cues. These effects interact with expectations and manner of presentation of such cues. What remains to be understood is the meaning and mechanism of the attention bias toward food cues in restrained eaters and the implications of such bias for overeating and overweight more broadly speaking.

Effects of Bite Count Feedback from a Wearable Device and Goal Setting on Consumption in Young Adults

BACKGROUND

New technologies are emerging that may help individuals engage in healthier eating behaviors. One paradigm to test the efficacy of a technology is to determine its effect relative to environment cues that are known to cause individuals to overeat.

OBJECTIVE

The purpose of this work was to independently investigate two questions: How does the presence of a technology that provides bite count feedback alter eating behavior? and, How does the presence of a technology that provides bite count feedback paired with a goal alter eating behavior?

DESIGN

Two studies investigated these research questions. The first study tested the effects of a large and small plate crossed with the presence or absence of a device that provided bite count feedback on intake. The second study tested the effects of a bite count goal with bite count feedback, again crossed with plate size, on intake. Both studies used a 2×2 between-subjects design.

PARTICIPANTS/SETTING

In the first study, 94 subjects (62 women aged 19.0±1.6 years with body mass index [BMI] 23.04±3.6) consumed lunch in a laboratory. The second study examined 99 subjects (56 women aged 18.5±1.5 years with BMI 22.73±2.70) under the same conditions.

INTERVENTION

In both studies subjects consumed a single-course meal, using either a small or large plate. In the first study participants either wore or did not wear an automated bite counting device. In the second study all participants wore the bite counting device and were given either a low bite count goal (12 bites) or a high bite count goal (22 bites).

STATISTICAL ANALYSES

Effect of plate size, feedback, and goal on consumption (grams) and number of bites taken were assessed using 2×2 analyses of variance. As adjunct measures, the effects of serving size, bite size (grams per bite), postmeal satiety, and satiety change were also assessed.

RESULTS

In the first study there was a main effect of plate size on grams consumed and number of bites taken such that eating from a large plate led to greater consumption (P=0.001) and a greater number of bites (P=0.001). There was also a main effect of feedback on consumption and number of bites taken such that those who received feedback consumed less (P=0.011) and took fewer bites (P<0.001). In the second study there was a main effect of plate size on consumption such that those eating from a large plate consumed more (P=0.003) but did not take more bites. Further analysis revealed a main effect of goal on number of bites taken such that those who received the low goal took fewer bites (P<0.001) but did not consume less.

CONCLUSIONS

Providing feedback on the number of bites taken from a wearable intake monitor can reduce overall intake during a single meal. Regarding the first research question, providing feedback significantly reduced intake in both plate size groups and reduced the overall number of bites taken. Regarding the second research question, participants were successful in eating to their goals. However, individuals in the low goal condition appeared to compensate for the restricted goal by taking larger bites, leading to comparable levels of consumption between the low and high goal groups. Hence, the interaction of technology with goals should be considered when introducing a health intervention.

In the eye of the beholder: Visual biases in package and portion size perceptions

As the sizes of food packages and portions have changed rapidly over the past decades, it has become crucial to understand how consumers perceive and respond to changes in size. Existing evidence suggests that consumers make errors when visually estimating package and portion sizes, and these errors significantly influence subsequent food choices and intake. We outline four visual biases (arising from the underestimation of increasing portion sizes, the dimensionality of the portion size change, labeling effects, and consumer affect) that shape consumers' perceptions of package and portion sizes. We discuss the causes of these biases, review their impact on food consumption decisions, and suggest concrete strategies to reduce them and to promote healthier eating. We conclude with a discussion of important theoretical and practical issues that should be addressed in the future.

Are You Sure? Confidence about the Satiating Capacity of a Food Affects Subsequent Food Intake

Expectations about a food’s satiating capacity predict self-selected portion size, food intake and food choice. However, two individuals might have a similar expectation, but one might be extremely confident while the other might be guessing. It is unclear whether confidence about an expectation affects adjustments in energy intake at a subsequent meal. In a randomized cross-over design, 24 subjects participated in three separate breakfast sessions, and were served a low-energy-dense preload (53 kcal/100 g), a high-energy-dense preload (94 kcal/100 g), or no preload. Subjects received ambiguous information about the preload’s satiating capacity and rated how confident they were about their expected satiation before consuming the preload in its entirety. They were served an ad libitum test meal 30 min later. Confidence ratings were negatively associated with energy compensation after consuming the high-energy-dense preload (r = −0.61; p = 0.001). The same relationship was evident after consuming the low-energy-dense preload, but only after controlling for dietary restraint, hunger prior to, and liking of the test meal (p = 0.03). Our results suggest that confidence modifies short-term controls of food intake by affecting energy compensation. These results merit consideration because imprecise caloric compensation has been identified as a potential risk factor for a positive energy balance and weight gain.

Portion size me: plate-size induced consumption norms and win-win solutions for reducing food intake and waste

Research on the self-serving of food has empirically ignored the role that visual consumption norms play in determining how much food we serve on different sized dinnerware. We contend that dinnerware provides a visual anchor of an appropriate fill-level, which in turn, serves as a consumption norm (Study 1). The trouble with these dinnerware-suggested consumption norms is that they vary directly with dinnerware size--Study 2 shows Chinese buffet diners with large plates served 52% more, ate 45% more, and wasted 135% more food than those with smaller plates. Moreover, education does not appear effective in reducing such biases. Even a 60-min, interactive, multimedia warning on the dangers of using large plates had seemingly no impact on 209 health conference attendees, who subsequently served nearly twice as much food when given a large buffet plate 2 hr later (Study 3). These findings suggest that people may have a visual plate-fill level--perhaps 70% full--that they anchor on when determining the appropriate consumption norm and serving themselves. Study 4 suggests that the Delboeuf illusion offers an explanation why people do not fully adjust away from this fill-level anchor and continue to be biased across a large range of dishware sizes. These findings have surprisingly wide-ranging win-win implications for the welfare of consumers as well as for food service managers, restaurateurs, packaged goods managers, and public policy officials.

Individual differences in susceptibility to large portion sizes among obese and normal-weight children

OBJECTIVE

Determine the association of children's susceptibility to large food portion sizes with appetite regulation and obesity.

METHODS

Normal-weight and obese non-Hispanic black children (n = 100) aged 5-6 years were observed in four dinner conditions of varying portion size; portions of all foods (except milk) offered were: 100% (677 kcal), 150% (1015 kcal), 200% (1353 kcal), or 250% (1691 kcal) of those in the reference condition (100%). Condition order was randomly assigned to 2-4 children who ate together at each meal. Child height and weight were measured and caregiver reports of child appetite were obtained. Hierarchical growth curve models were used to estimate associations of meal energy intake with portion size condition, child weight status, and appetite regulation traits, controlling for demographics.

RESULTS

Total energy intake increased across conditions of increasing food portion size (P < 0.001). The effect of portion size condition on total energy intake varied with food responsiveness (P = 0.05) and satiety responsiveness (P < 0.05), but not weight status (P = 0.682). Children with lower satiety responsiveness and greater food responsiveness showed greater increases in meal energy across conditions.

CONCLUSIONS

Children with poorer appetite regulation may be more vulnerable to obesogenic dietary environments offering large food portions than other children.

A qualitative study of parents' perceptions and use of portion size strategies for preschool children's snacks

OBJECTIVE

Increases in childhood obesity correspond with shifts in children's snacking behaviors and food portion sizes. This study examined parents' conceptualizations of portion size and the strategies they use to portion snacks in the context of preschool-aged children's snacking.

METHODS

Semi-structured qualitative interviews were conducted with non-Hispanic white (W), African American (AA), and Hispanic (H) low-income parents (n = 60) of preschool-aged children living in Philadelphia and Boston. The interview examined parents' child snacking definitions, purposes, contexts, and frequency. Verbatim transcripts were analyzed using a grounded theory approach. Coding matrices compared responses by race/ethnicity, parent education, and household food security status.

RESULTS

Parents' commonly referenced portion sizes when describing children's snacks with phrases like "something small." Snack portion sizes were guided by considerations including healthfulness, location, hunger, and timing. Six strategies for portioning snacks were presented including use of small containers, subdividing large portions, buying prepackaged snacks, use of hand measurement, measuring cups, scales, and letting children determine portion size. Differences in considerations and strategies were seen between race/ethnic groups and by household food security status.

CONCLUSIONS

Low-income parents of preschool-aged children described a diverse set of considerations and strategies related to portion sizes of snack foods offered to their children. Future studies should examine how these considerations and strategies influence child dietary quality.

What is the role of portion control in weight management?

Systematic studies have shown that providing individuals with larger portions of foods and beverages leads to substantial increases in energy intake. The effect is sustained over weeks, supporting the possibility that large portions have a role in the development of obesity. The challenge is to find strategies to effectively manage the effects of portion size. One approach involves teaching people to select appropriate portions and to use tools that facilitate portion control. Although tools such as portion-control plates have been shown in several randomized trials to improve weight loss, limited data are available on whether education and tools lead to long-term changes in eating behavior and body weight. Another approach is to use preportioned foods (PPFs) to add structure to meals and minimize decisions about the amount of food to eat. A number of randomized controlled trials have demonstrated the efficacy of both liquid meal replacements and solid PPFs for weight loss and weight loss maintenance, but it is not known if they lead to better understanding of appropriate portions. Although portion control is important for weight management, urging people simply to 'eat less' of all foods may not be the best approach as high-energy-dense foods disproportionately increase energy intake compared with those lower in energy density. A more effective strategy may be to encourage people to increase the proportion of foods low in energy density in their diets while limiting portions of high-energy-dense foods. If people lower the energy density of their diet, they can eat satisfying portions while managing their body weight.

Role of child weight status and the relative reinforcing value of food in children's response to portion size increases

OBJECTIVE

Food portion size is an important determinant of intake in children. It remains unknown if children's weight status and relative reinforcing value of food (RRVF) interact with portion size to affect intake.

METHODS

In a randomized crossover design, 25 normal-weight and 25 obese children, ages 8-10 years, consumed dinner once a week for 3 weeks. At each dinner, the same meal was served, but the portion size of all foods (chicken nuggets, hash browns, ketchup, green beans, brownies) and a sugar-sweetened beverage (fruit punch) varied across conditions (100, 150, and 200%). Children's RRVF was assessed using a behavioral choice task.

RESULTS

There was a significant main effect of portion size condition (P = 0.003) and weight status (P = 0.0005) and a nonsignificant trend for a portion size-by-weight status interaction (P = 0.108) on intake. Mean intakes across conditions (100, 150, and 200%) were 801 ± 57, 964 ± 58, and 873 ± 57 kcal for normal-weight children and 1041 ± 57, 1129 ± 57, and 1210 ± 57 kcal for obese children, respectively. Neither the main effect of RRVF status nor the condition-by-RRVF status interaction was significant (P > 0.48).

CONCLUSIONS

Environments that offer large portions of palatable foods affect all children's intake irrespective of their weight status or how reinforcing they find food to be.