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Recent research suggests that ultraprocessed foods, particularly as defined by the NOVA system, facilitate overconsumption and may contribute to the development of obesity. Questions remain as to what properties of ultraprocessed foods are driving excess intake. Ultraprocessed foods tend to be high in energy density and low in volume, easy to eat rapidly, and highly palatable. Studies indicate that these properties are likely contributors to the overconsumption of ultraprocessed foods, rather than the processing per se. Indeed, processing can be used to modify food properties such as energy density and texture to help reduce overconsumption. For many people, ultraprocessed foods provide accessible and affordable sources of nutrients and energy when unprocessed foods are scarce. Future studies should focus on understanding how processing can be used to create widely available and affordable nutrient-rich foods that can help consumers manage energy intake. [ABSTRACT FROM AUTHOR]

In a 1987 paper, addressing questions about factors that influence the initiation, maintenance, and termination of food intake, we wrote, "development of systematic procedures to measure eating behaviour is essential if descriptive and inferential statistics are to be applied to answering such questions, giving them power and replicability" (Hetherington & Rolls, 1987 page 77). Therefore, as longstanding advocates of rigorous procedures in laboratory-based investigations of food intake, we welcome Robinson et al.'s (2018) clear recommendations for laboratory studies. However, this is akin to voting for "motherhood and apple pie", and few would argue against deployment of improved procedures for these studies. What then can we contribute to the debate in order to refine the recommendations made or add to them? Our most important message for researchers is that the central hypothesis or main research question will determine the most appropriate methods for any study. If a laboratory-based study is planned, then there are basic methodological questions that must be answered before proceeding to a final protocol. While such guidelines are needed to ensure basic methodological rigour, these should not be so prescriptive as to inhibit creativity. Here we provide several thoughts on how to advance studies of ingestive behaviour, including the need to apply appropriate controls, encouragement to move beyond convenience samples, and to remember the value of exploratory, observational, and naturalistic studies to complement laboratory-based studies. [ABSTRACT FROM AUTHOR]

I describe my 50 year career in ingestive behavior in the hope of inspiring young scientists to join in the excitement of discovering why animals, especially the human animal, eat and drink. My interest in ingestive behavior started by chance in a freshman biology class at the University of Pennsylvania taught by Alan Epstein. Once I was exposed to the thrill of doing research my plans for medical school were abandoned and I traveled to the University of Cambridge in England where with James Fitzsimons I completed a Ph.D. in physiology on studies of thirst in rats. After I moved on to the University of Oxford, the early training in biologic mechanisms provided a good basis for studies in humans. We characterized the sensations associated with thirst and the mechanisms involved in its initiation and termination. We also continued to work with animal models in a series of studies of dietary obesity. The effect of dietary variety on rat's intake led to studies of sensory-specific satiety in humans. In recent years the primary interest of my lab has been how food properties affect intake, satiety, and body weight. At the Johns Hopkins School of Medicine and now at The Pennsylvania State University, we have conducted systematic studies of the effects of the macronutrients, variety, portion size, and energy density in both adults and children. Currently our research aims to understand how to leverage the robust effects of variety, portion size, and energy density to encourage healthy eating and drinking. Throughout my career I have been lucky to have been in supportive environments surrounded by creative, insightful, and diligent colleagues. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ghrelin and PYY increased in response to reduced ED and consequent weight loss. [•] Low-ED diets were associated with lesser increases ghrelin across the intervention. [•] Low-ED diets tended to be associated with increases in PYY. [•] Reductions in ED may promote weight loss by blunting orexigenic hormone responses. [ABSTRACT FROM AUTHOR]

Although several studies have investigated the influence of nutrition labelling on food intake, the effect of labels indicating a food's satiating power on food intake and sensory-specific satiation (SSS) is poorly understood. We investigated whether providing information about the satiating power of a meal affects intake and SSS. Participants (19 men and 18 women) consumed the same test meal of pasta salad ad libitum on two occasions, once described as 'light' and once as 'filling'. SSS was determined as the change in liking of the flavor and desire to eat the test meal before and after consumption, compared to seven uneaten foods. As hypothesized, intake increased by a mean (±SD) of 31 ± 59 g and 42 ± 81 kcal when the meal was labelled 'light' as opposed to 'filling' (p < 0.01). After eating, ratings for both liking and desire to eat decreased significantly more for the test meal than for the uneaten control foods (p < 0.001), demonstrating SSS. These relative changes in liking and desire to eat did not differ between the label conditions, despite differences in intake. Furthermore, accounting for amount consumed, the magnitude of SSS did not differ between the label conditions, which suggests that it did not explain the effect of the labels on intake. This study shows that labels indicating the satiating power of a meal can affect intake, warranting caution in the use of such labels on products intended to reduce intake. [ABSTRACT FROM AUTHOR]

Serving larger portions of energy-dense foods has been shown to promote children's energy intake at meals. Whether larger portions increase children's intake of both fruits and vegetables (F&V) is less clear. A 2×2 within-subjects design systematically varied portion sizes of fruit (75 vs 150 g) and vegetable (75 vs 150 g) side dishes served at dinner. Children's F&V liking was measured using a validated tasting method. Thirty children aged 4 to 6 years were tested in a laboratory setting at 5:00 pm on weekdays from November 2008 through March 2009. Mixed linear models were used to determine effects of fruit portion size, vegetable portion size, and their interaction on food and energy intakes. Data are presented as model-based means±standard error unless otherwise indicated. When portions were doubled, children increased their vegetable intake by 37% (12±4 g; P<0.01) and their fruit intake by 70% (41±6 g; P<0.01). Vegetable portion size effects were not influenced by offering more fruit and vice versa. Portion size effects were limited to children who liked that particular food. Total meal energy intake did not vary by portion size condition. These results indicate that serving larger F&V portions at meals can be used to promote young children's intake of both foods without influencing total meal energy intake. Effects were not seen in children who disliked F&V, suggesting a need to combine increased F&V portions with strategies to increase their acceptance. [Copyright &y& Elsevier]

Abstract: Much of the research in ingestive behavior has focused on the macronutrient composition of foods; however, these studies are incomplete, or could be misleading, if they do not consider the energy density (ED) of the diet under investigation. Lowering the ED (kcal/g) by increasing the volume of preloads without changing macronutrient content can enhance satiety and reduce subsequent energy intake at a meal. Ad libitum intake or satiation has also been shown to be influenced by ED when the proportions of macronutrients are constant. Since people tend to eat a consistent weight of food, when the ED of the available foods is reduced, energy intake is reduced. The effects of ED have been seen in adults of different weight status, sex, and behavioral characteristics, as well as in 3- to 5-year-old children. The mechanisms underlying the response to variations in ED are not yet well understood and data from controlled studies lasting more than several days are limited. However, both population-based studies and long-term clinical trials indicate that the effects of dietary ED can be persistent. Several clinical trials have shown that reducing the ED of the diet by the addition of water-rich foods such as fruits and vegetables was associated with substantial weight loss even when patients were not told to restrict calories. Since lowering dietary energy density could provide effective strategies for the prevention and treatment of obesity, there is a need for more studies of mechanisms underlying the effect and ways to apply these findings. [Copyright &y& Elsevier]

Abstract: Consuming whole fruit reduces ratings of satiety more than fruit juice, but little is known about the effects of different forms of fruit on subsequent energy intake. This study tested how consuming preloads of apples in different forms prior to a meal (apple, applesauce, and apple juice with and without added fiber) influences satiety and energy intake at meal. Preloads were matched for weight, energy content, energy density, and ingestion rate. Once a week for 5 weeks, 58 adults consumed one of four preloads (266g; 125kcal [523kJ]), or no preload (control), followed by a test meal consumed ad libitum 15min later. Results showed that eating apple reduced lunch energy intake (preload+test meal) by 15% (187±36kcal [782±151kJ]) compared to control (p <0.0001) and decreased energy intake compared to applesauce and both juices. Fullness ratings differed significantly after preload consumption (apple>applesauce>both juices>control). Overall, whole apple increased satiety more than applesauce or apple juice. Adding naturally occurring levels of fiber to juice did not enhance satiety. These results suggest that solid fruit affects satiety more than pureed fruit or juice, and that eating fruit at the start of a meal can reduce energy intake. [Copyright &y& Elsevier]

Abstract: In three cross-over experiments, we examined the effect on energy intake of changing the size of the plate used at a meal. On separate days, adults were served the same lunch menu but were given a different-sized plate. In the first study, 45 participants used each of three plate sizes (17, 22, or 26cm) and served the main course from a large dish. In the second study, 30 participants received an equal amount of food presented on each of the two larger plates. In the third study, 44 participants used each of the three plates and selected from a buffet of five foods matched for energy density. Results showed that plate size had no significant effect on energy intake. The mean differences in intake using the smallest and largest plates in the three studies were 21±13g, 11±13g, and 4±18g, respectively, equivalent to <142kJ (34kcal) and not significantly different from zero. Participants in the third study made significantly more trips to the buffet when they were given the smallest plate. These findings show that using a smaller plate did not lead to a reduction in food intake at meals eaten in the laboratory. [Copyright &y& Elsevier]

Abstract: Consuming soup can enhance satiety and reduce energy intake. Little is known about the influence on energy intake and satiety of varying the form of soup by altering the blending of ingredients. We tested the effects on meal intake of consuming different forms of soup as a preload: broth and vegetables served separately, chunky vegetable soup, chunky-pureed vegetable soup, or pureed vegetable soup. Normal-weight men and women (n=60) came to the laboratory for lunch once a week for 5 weeks. Each week, one of four compulsory preloads, or no preload, was consumed prior to lunch. A test meal was consumed ad libitum 15min after the soup was served. Results showed that consuming soup significantly reduced test meal intake and total meal energy intake (preload + test meal) compared to having no soup. When soup was consumed, subjects reduced meal energy intake by 20% (134±25kcal; 561±105kJ). The type of soup had no significant effect on test meal intake or total meal energy intake. Consuming a preload of low-energy-dense soup, in a variety of forms, is one strategy for moderating energy intake in adults. [Copyright &y& Elsevier]

Abstract: Objective: We tested the effect on energy intake of increasing the portion size of all foods and beverages served over 2 consecutive days. Design: The study used a randomized crossover design. Subjects/setting: Subjects were 32 adults from a university community. Intervention: For 2 consecutive days in each of 3 weeks, subjects ate their main meals in a controlled setting and were given snacks for consumption between meals. We used the same two daily menus each week, but varied the portion sizes of all foods and beverages served in a given week (either 100%, 150%, or 200% of baseline amounts). Main Outcome Measures: Energy intake and ratings of hunger and satiety were measured. Statistical Analyses Performed: A linear mixed model with repeated measures was used. Results: There was a significant effect of portion size on energy intake in both men and women (P<0.0001). Increasing portions by 50% increased daily energy intake by 16% (women: 335 kcal/day; men: 504 kcal/day), and increasing portions by 100% increased intake by 26% (women: 530 kcal/day; men: 812 kcal/day). Energy intake did not differ between the 2 days of each week. Daily ratings of fullness were lowest in the 100% portion condition (P=0.0004), but did not differ significantly in the 150% and 200% conditions. Conclusions: Increasing the portion size of all foods resulted in a significant increase in energy intake that was sustained over 2 days. These data support suggestions that large portions are associated with excess energy intake that could contribute to increased body weight. [Copyright &y& Elsevier]

Abstract: A growing body of laboratory-based, clinical, and epidemiological data suggests that low-energy-dense diets are associated with better diet quality, lower energy intakes, and body weight. Dietary energy density can be lowered by adding water-rich fruits, vegetables, cooked grains, and soups to the diet, and by reducing the diet’s fat content. Low-energy-dense diets can be successfully incorporated into clinical dietetics since they help lower energy intake without reducing food volume and thus help individuals avoid feeling hungry and deprived. There are multiple steps that could be taken by nutrition professionals and food manufacturers to encourage the consumption of low-energy-dense diets. The goal is to develop reduced-calorie eating plans that meet personal food preferences and also provide satisfying food portions. Since using energy density to guide food choices leads to food patterns consistent with dietary guidelines, policy level initiatives should be devised to help ensure that low-energy-dense diets are affordable and accessible to all. [Copyright &y& Elsevier]

Abstract: Objective: We tested the effect on meal intake of varying the energy density and portion size of a compulsory first-course salad. Design: The study used a randomized crossover design. Subjects/setting: Forty-two women from the State College, PA, university community ate lunch in the laboratory once per week for 7 weeks. Intervention: Lunch comprised one of six first-course salads, or no salad in the control condition, followed by a main course of pasta. Subjects were required to consume the entire salad, but ate as much pasta as they wanted. The salads varied in energy density (0.33, 0.67, or 1.33 kcal/g) and portion size (150 or 300 g). The energy density of the salad was reduced by changing the amount and type of dressing and cheese. Main outcome measures: Energy intake and ratings of hunger, satiety, and food characteristics were measured. Statistical analyses performed: Outcomes were analyzed using a linear mixed model with repeated measures. Results: Compared with having no first course, consuming the low-energy-dense salads reduced meal energy intake (by 7% for the small portion and 12% for the large), and consuming the high-energy-dense salads increased intake (by 8% for the small portion and 17% for the large). When two salads with the same number of calories were compared, meal intake was decreased when the large portion of the lower-energy-dense salad was consumed. Conclusions: Eating a low-energy-dense first course enhances satiety and reduces meal energy intake. Consuming a large portion of a low-energy-dense food at the start of a meal may be an effective strategy for weight management. [Copyright &y& Elsevier]

The energy density (kcal/g) and the portion size (g) of foods have been identified as two properties of foods that can modulate energy intake. Recent studies have shown that when either the energy density or the portion size of foods is increased, energy intake increases. Within a meal, when both factors are increased simultaneously, their effects are independent and add together to increase energy intake. On the other hand, reducing the energy density of a first course, while increasing the volume that is consumed, leads to a decrease in energy intake at the entire meal. The mechanisms by which both factors exert their influence are not well understood but likely include cognitive and orosensory factors as well as physiological controls related to gastric distention and gastric emptying. Findings from studies in this area of research provide evidence that the energy density and the portion size of foods are important determinants of energy intake. An environment in which the food supply is ample and large portions of energy-dense foods are readily available to consumers can contribute to an overconsumption of calories. [Copyright &y& Elsevier]

Objective: This study investigated the effect on energy intake of increasing the portion size of a food served as a discrete unit.Design: A within-subject design with repeated measures was used.Subjects/setting: The sample comprised 75 young adults (37 females and 38 males) from a university community.Intervention: Individuals ate lunch in the lab once a week for 4 weeks. Each week, they were served one of four sizes of a deli-style sandwich (6, 8, 10, or 12 inches), of which they could eat as much as they wanted.Main outcome measures: Energy intakes were determined for each meal, as were ratings of hunger and satiety before and after each meal.Statistical analyses performed: A linear mixed model with repeated measures was used. The influence of subject characteristics was examined using analysis of covariance.Results: The portion size of the sandwich significantly influenced lunch intake for both males and females (P<.0001). The majority of individuals consumed the entire 6-inch sandwich. When served the 12-inch sandwich, compared with the 8-inch sandwich, females consumed 12% more energy (74 kcal) and males consumed 23% more energy (186 kcal). Despite these differences, ratings of hunger and fullness were not significantly different after eating the 12-inch and 8-inch sandwiches.Applications/conclusions: These results suggest that increasing the portion size of a food served as a discrete unit leads to increased energy intake at a single meal without differentially influencing ratings of hunger and satiety. Dietitians should educate their clients about strategies to moderate the effect on intake of increased portions of high-calorie foods. [Copyright &y& Elsevier]

The objective of this study was to determine how the portion size of a packaged snack affects energy intake of the snack and of the subsequent meal. On five separate days, 60 subjects (34 women and 26 men) ate an afternoon snack and dinner in individual cubicles. For each snack, subjects were served one of five packages of potato chips (28, 42, 85, 128, or 170 g), which they consumed ad libitum directly from the unlabelled, opaque package. Subjects returned to the lab three hours later for a standard dinner, which was also consumed ad libitum. Results showed that snack intake increased significantly as the package size increased for both males and females (p<0.0001). The combined energy intake from snack and dinner also increased as the package size increased. On average, when served the largest snack package compared to the smallest, subjects consumed an additional 596 kJ (143 kcal) at snack and dinner combined. Results from this study demonstrate that short-term energy intake increases with increasing package size of a snack. These data suggest that the availability of large packages of energy-dense snacks may be one of the environmental influences associated with excess energy intake. [Copyright &y& Elsevier]

Examines the effects of fruit and vegetables on intake regulation and body weight. Body mass index; Reduction in energy density; Decrease in energy intake; Promotion of satiety.

The article reports that large portions of energy-dense foods are contributing to the obesity epidemic in the U.S. People eat in units, and larger units or portions mean that they eat more. Some steps that could be taken to address the problem include education and consumer awareness, food labels with portion size and more point-of-purchase nutrition information.

This experiment examined whether food volume and energy content affected satiety in lean and obese women, when visual and oral cues were bypassed by infusing food intragastrically. The effects of volume and energy content were examined separately by using liquid foods that differed in energy density (kcal/g). On 5 separate days, 25 lean and 29 obese women consumed all of their meals in the laboratory. A nasogastric tube was inserted 30 min before lunch on 4 days; on three of these occasions, a liquid preload was infused for 15 min and, on the fourth occasion (control), the preload was diverted covertly. On the remaining day, no tube was inserted. The three preloads varied two-fold in volume and energy content: 200 ml/200 kcal, 400 ml/200 kcal and 400 ml/400 kcal. The results showed that increasing the volume of infused food, but not the energy content, affected satiety in both lean and obese women. There was a mean decrease in energy intake at lunch of 77 kcal (13%) after the 400-ml preload compared with the iso-energetic 200-ml preload (P=.013). Increasing the energy content of infused food, but not the volume, did not affect satiety. Thus, when sensory cues were bypassed, the volume of liquid food infused intragastrically affected subsequent energy intake in both lean and obese women. These results suggest that gastric and postgastric mechanisms are involved in the effects of high-volume, low-energy-dense foods on satiety. [Copyright &y& Elsevier]

Explores the role of energy density in the overconsumption of fat. Role of the energy density of food in satiety; Examination on whether macronutrients differ in their effects on satiation; Variations in the fat content or energy density of a portion of the diet; How energy density affect energy intake.

• The reasons individuals stop eating questionnaire (RISE-Q) characterizes satiation. • The RISE-Q identified factors that represent processes that contribute to satiation. • The satiation framework depicts various processes leading to meal termination. • The salience of these processes depends on context and food properties. • The satiation framework will aid understanding of the nature of meal termination. Satiation has been described as a process that leads to the termination of eating and controls meal size. However, studies have shown that the termination of eating can be influenced by multiple behavioral and biological processes over the course of a meal as well as those related to the context in which the meal is consumed. To expand understanding of how individuals experience satiation during a meal, we recently developed the Reasons Individuals Stop Eating Questionnaire (RISE-Q). The development of the RISE-Q revealed five distinct factors reported to contribute to meal termination: Planned Amount, Self-Consciousness, Decreased Food Appeal, Physical Satisfaction, and Decreased Priority of Eating. Thus, we define satiation as a series of dynamic processes that emerge over the course of a meal to promote meal termination. We suggest that each of the factors identified by the RISE-Q represents a distinct process, and illustrate the contribution of each process to meal termination in the Satiation Framework. Within this framework the prominence of each process as a reason to stop eating likely depends on meal context in addition to individual variability. Therefore, we discuss contexts in which different processes may be salient as determinants of meal termination. Expanding the definition of satiation to include several dynamic processes as illustrated in the Satiation Framework will help to stimulate investigation and understanding of the complex nature of meal termination. [ABSTRACT FROM AUTHOR]

Tests the hypothesis on the influence of fat content information of preload or required first course to women's subsequent intake of energy foods. Description of study subjects; Use of balanced, repeated-measures design in four sessions; Meals components; Analysis of energy intake; Macronutrient intake; Visual analog scale ratings.

Interventions designed to improve children's self-regulation of energy intake have yielded mixed results. We tested the efficacy of a technology-enhanced intervention designed to teach children to eat in response to internal hunger and fullness cues. Thirty-two children (mean age 4.9 ± 0.8 y) completed this within-subjects, pre-post design study that took place across 10 laboratory sessions, each scheduled approximately 1 week apart. The intervention was conducted across weeks 4-7 in small groups focused on teaching children how food travels through the body and how to respond to hunger and fullness signals. Children's short-term energy compensation, a measure of intake regulation, was collected at baseline and follow-up using a preloading protocol. Twenty-five minutes prior to receiving a standardized test meal, children consumed a low-energy (3 kcal) or high-energy (150 kcal) preload beverage, presented in random order at baseline and follow-up. Knowledge of intervention concepts was also assessed at baseline and follow-up. Linear mixed models were used to examine changes in short-term energy compensation and knowledge from baseline to follow-up. Knowledge related to the intervention improved from baseline to follow-up (3.5 ± 0.3 to 7.0 ± 0.3 correct responses out of a possible 10; P < 0.001). Children's energy compensation also improved from baseline to follow-up, as evidenced by a time-by-preload condition interaction (P = 0.02). However, this improvement was driven by boys who increased the adjustment for beverage energy content from baseline to follow-up (P = 0.04). Girls showed no change in energy compensation with the intervention (P = 0.58). The overall increase in knowledge, paired with the improvement in energy compensation in boys, suggests that this technology-enhanced intervention may be efficacious for some children. Further research is needed to determine whether boys and girls will benefit from different, personalized intervention strategies for obesity prevention. [ABSTRACT FROM AUTHOR]

Individuals managing their weight are often faced with problem foods that are difficult to resist eating. In the context of a weight-loss intervention, we characterized the most commonly reported problem foods and the behavioral strategies used to manage them, and examined which strategies were related to weight loss. Women with overweight and obesity (N = 186) participated in a one-year randomized trial of three interventions (NCT01474759): standard advice to eat less food, choosing portions based on energy density, and using pre-portioned foods. At Months 0, 6, and 12 of the trial, participants listed the foods they found most problematic and reported the frequency of using eight behavioral strategies to control intake of these foods, including three practices for avoiding exposure to problem foods and three for consuming them but limiting intake. The responses showed that 82% of the top three problem foods were in the categories of sweet baked items, salty snacks, starchy side dishes, chocolate and candy, and ice cream. After one year, women who reported more frequently using the strategy of limiting portions of problem foods had a greater rate of weight loss (kg/week), regardless of their intervention group (p < 0.0001). Among women who limited portions of problem foods less frequently, those using pre-portioned foods had greater initial weight loss compared to the other two groups, but then regained weight at a greater rate (p < 0.0001). The three avoidance strategies for problem foods were reported to be frequently used but were not found to be related to weight loss. These results suggest that adopting and maintaining strategies to manage portions of problem foods, rather than avoiding exposure to them, can be a more useful approach for weight loss. [ABSTRACT FROM AUTHOR]

Provides information on a study which examined the effects of portion size on children's food intake, and tested the prediction that the effects of portion size on children's food intake will be greater for 5-year-old than 3-year-old children. Subjects and methods; Results; Discussion.

Larger portions of food elicit greater intake than smaller portions of food, particularly when foods are high in energy density (kcal/g; ED). The neural mechanisms underlying this effect remain unclear. The present study used fMRI to assess brain activation to food (higher-ED, lower-ED) and non-food (office supplies) images presented in larger and smaller (i.e., age-appropriate) amounts in 61, 7-8-year-olds (29 male, 32 female) without obesity. Larger amounts of food increased activation in bilateral visual and right parahippocampal areas compared to smaller amounts; greater activation to food amount (larger > smaller) in this cluster was associated with smaller increases in food intake as portions increased. Activation to amount (larger > smaller) was stronger for food than office supplies in primary and secondary visual areas, but, for office supplies only, extended into bilateral parahippocampus, inferior parietal cortex, and additional visual areas (e.g., V7). Activation was greater for higher-vs. lower-ED food images in ventromedial prefrontal cortex for both larger and smaller amounts of food; however, this activation extended into left lateral orbital frontal cortex for smaller amounts only. Activation to food cues did not differ by familial risk for obesity. These results highlight potentially distinct neural pathways for encoding food energy content and quantity. [ABSTRACT FROM AUTHOR]

Abstract Aim The robust effect of portion size on intake has led to growing interest in why individuals consume more food when served larger portions. A number of explanations have been proposed, and this review aims to provide insight into potential underlying factors by summarizing recent studies testing moderators of the portion size effect. Summary of findings Provision of portion size information, such as through labeling or training in portion control, failed to attenuate food intake in response to increasing meal size. This indicates that a lack of knowledge about appropriate portions may not be sufficient to explain the portion size effect. In contrast, there is evidence for a role of decision making in the response to large portions, with value being one consideration of importance. The portion size effect may be more closely related to the inherent value of food than monetary value, since provision of the opportunity to take away uneaten food after a meal, which can reduce food waste, attenuated the portion size effect but variations in pricing did not. A number of studies also support an influence of orosensory processing on the portion size effect; large portions have been shown to relate to increased bite size and faster eating rate. Reduced oral processing time when consuming large portions could contribute to the effect by delaying sensory-specific satiety. Findings from a recent study supported this by demonstrating that sensory-specific satiety did not differ between larger and smaller portions despite substantial differences in intake. Conclusions A number of moderators of the portion size effect have been identified, including factors related to the environment, the food, and the individual. It is likely that multiple variables contribute to the response to large portions. Future research should aim to determine the relative contribution of explanatory variables across different contexts and individuals. Highlights • We review recent studies designed to provide insight into factors underlying the PSE. • Environmental, food, and consumer-related moderators of the PSE have been identified. • It is likely that multiple factors work in combination to drive the PSE. • The relative contribution of these factors differs across contexts and individuals. • We use a model to illustrate the complex interplay between factors underlying the PSE. [ABSTRACT FROM AUTHOR]

Highlights the symposium Modifying the Food Environment: Energy, Density, Food Costs and Portion Size during the 2004 Experimental Biology meeting in Washington D.C. on April 19, 2004. Theme of the symposium; Sponsors; Contact information.

Purpose: Recent public health messages have advised consumers to lower dietary energy density (ED) for weight management, but it is not known whether the proportion of the diet from low-ED foods is related to weight status. In a nationally representative sample of US adults, we evaluated whether the proportions of dietary energy intake contributed by low- and high-ED foods are associated with body mass index (BMI) and waist circumference (WC).Methods: Data were from a cross-sectional sample of 9551 adults ≥18 years in the 2005–2008 National Health and Nutrition Examination Survey (NHANES). ED (kcal/g) was calculated for each food item reported during a 24-h dietary recall; individual foods were divided into five ED categories: very low ED (<0.6 kcal/g), low ED (0.6–1.5 kcal/g), medium ED (1.51–2.25 kcal/g), high ED (2.26–4.0 kcal/g), and very high ED (>4.0 kcal/g). The percentages of total energy and the food weight from each category were evaluated by BMI and WC after controlling for total energy intake and other covariates.Results: Men classified as lean (BMI < 25 kg/m2) reported consuming a greater proportion of total energy from very low- and low-ED foods (7.2 %very low and 23.3 %low), compared to men considered obese ((BMI > 30 kg/m2); 5.2 %very low and 20.1low %; p-trends <0.001very low, 0.002low). Similarly, women classified as lean reported intakes of very low-ED foods of 7.8 % (vs. 6.4 % for women with obesity) of total energy and low-ED foods of 24.7 % (vs. 21.5 % for women with obesity) of total energy (p-trends 0.007very low, 0.004low). Men and women with obesity reported greater proportions of energy from high-ED foods (45.9 %men with obesity vs. 42.4 %lean men, 44.2 %women with obesity vs. 39.9 %lean women) with significant statistical trends (men = 0.008, women = 0.0005). Similar patterns were observed for intakes of proportions of very low-, low-, and high-ED foods and WC.Conclusion: Higher proportions of energy intake and food weight contributed by very low- and low-ED foods are associated with lower BMI (and WC). [ABSTRACT FROM AUTHOR]

Consuming soup can enhance satiety and reduce energy intake. Little is known about how varying the form of soup by altering the way in which ingredients are blended can influence energy intake and satiety. We tested the effects of consuming different forms of soup prior to a meal (separate broth and vegetables, chunky soup, chunky-pureed soup, or pureed soup) on subsequent lunch intake. Normal-weight, adult men and women (n=59) came to the lab for breakfast and lunch once a week for 5 weeks. Before each lunch, one of 4 compulsory preloads, or no preload, was served. Identical ingredients were used in all soups, but each was blended differently to vary the form and viscosity. A pasta lunch was consumed ad libitum 15 min after the soup was served. In women, consuming soup prior to lunch significantly reduced lunch intake (p<0.0001) and total meal energy intake (soup + lunch) (p<0.0001) compared to no preload. When soup was consumed prior to lunch, women reduced total meal intake by 17% (102 ± 28 kcal). In men, the chunky, chunky-pureed, and pureed soups reduced lunch intake and total meal energy intake more than the broth and vegetables and no preload (p<0.0001). When consuming the chunky, chunky-pureed, or pureed soup prior to lunch, men reduced total meal intake by 23% (167 ± 42 kcal). Consuming various forms of low-energy dense soup before a meal is one strategy that can be used to moderate energy intake in adults. [ABSTRACT FROM AUTHOR]

Portion size affects intake, but when all foods are served in large portions, it is unclear whether every food will be consumed in greater amounts. We varied the portion size (PS) of all foods at a meal to investigate the influence of food energy density (ED) on the PS effect as well as that of palatability and subject characteristics. In a crossover design, 48 women ate lunch in the laboratory on four occasions. The meal had three medium-ED foods (pasta, bread, cake) and three low-ED foods (broccoli, tomatoes, grapes), which were simultaneously varied in PS across meals (100%, 133%, 167%, or 200% of baseline amounts). The results showed that the effect of PS on the weight of food consumed did not differ between medium-ED and low-ED foods (p < 0.0001). Energy intake, however, was substantially affected by food ED across all portions served, with medium-ED foods contributing 86% of energy. Doubling the portions of all foods increased meal energy intake by a mean (±SEM) of 900 ± 117 kJ (215 ± 28 kcal; 34%). As portions were increased, subjects consumed a smaller proportion of the amount served; this response was characterized by a quadratic curve. The strongest predictor of the weight of food consumed was the weight of food served, both for the entire meal (p < 0.0001) and for individual foods (p = 0.014); subject characteristics explained less variability. Intake in response to larger portions was greater for foods that subjects ranked higher in taste (p < 0.0001); rankings were not related to food ED. This study demonstrates the complexity of the PS effect. While the response to PS can vary between individuals, the effect depends primarily on the amounts of foods offered and their palatability compared to other available foods. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Highlights: [•] Energy density was reduced by three methods and daily energy intakes were compared. [•] The methods were reducing fat, increasing fruit and vegetables, and adding water. [•] All three methods of reducing energy density decreased daily energy intake. [•] Decreasing the fat content led to the greatest decrease in daily energy intake. [•] Ratings of hunger and fullness over the day were not different across the methods. [ABSTRACT FROM AUTHOR]

Abstract: Effective strategies are needed to increase vegetable intake in accordance with health recommendations. Previous research has shown that increasing the variety of foods leads to increased consumption, yet this strategy has not been investigated for promoting vegetable intake. This crossover study, conducted in 2008 and 2009, tested whether filling half the plate with a variety of vegetables influences vegetable consumption and meal energy intake. Once a week for 4 weeks, a meal of pasta and cooked vegetables was consumed ad libitum by 66 adults (34 women, 32 men). The meals were varied in the type of vegetables offered: at three meals 600 g of a single vegetable was served (broccoli, carrots, or snap peas) and at one meal 200 g of each of the three vegetables was served side by side. Data were analyzed using a mixed linear model with repeated measures. In this study, serving a variety of vegetables increased vegetable intake at the meal (P<0.0001). Subjects ate more vegetables when served the variety than when served any single type; the mean increase was 48±6 g, or more than one-half serving. This increase remained significant when intake of the variety of vegetables was compared with the preferred vegetable of each participant (mean 25±8 g; P=0.002). Vegetable intake was not significantly related to energy intake at the meal. The results of this study demonstrate that increasing the variety of low-energy-dense vegetables served at a meal can be used as a strategy to increase vegetable intake. [Copyright &y& Elsevier]

Abstract: In a previous study, consuming a fixed amount of low-energy-dense salad as a first course reduced meal energy intake. We investigated whether this effect depended on serving salad before rather than with the main course, or on compulsory rather than ad libitum consumption. On five occasions, 46 women consumed ad libitum a main course of pasta, accompanied four times by low-energy-dense salad (300g; 100kcal [418kJ]). At two meals the salad was served 20min before the pasta (once compulsory; once ad libitum), and at two meals the salad was served with the pasta (once compulsory; once ad libitum). Results showed that adding a fixed amount of salad to the meal reduced energy intake by 11% (57±19kcal [238±79kJ]). Ad libitum salad consumption was less than compulsory consumption and did not significantly affect energy intake. Across all participants, the timing of serving the salad did not significantly influence energy intake, but the effect of timing depended on participant scores for flexible dietary restraint. Consuming low-energy-dense salad before rather than with the main course increased vegetable consumption by 23%. To moderate energy intake, maximizing the amount of salad eaten may be more important than the timing of consumption. [Copyright &y& Elsevier]

Abstract: The present study examined a dietary approach – lowering energy density – for producing weight loss in obese patients with binge eating disorder (BED) who also received cognitive-behavioral therapy (CBT) to address binge eating. Fifty consecutive participants were randomly assigned to either a six-month individual treatment of CBT plus a low-energy-density diet (CBT+ED) or CBT plus General Nutrition counseling not related to weight loss (CBT+GN). Assessments occurred at six- and twelve-months. Eighty-six percent of participants completed treatment, and of these, 30% achieved at least a 5% weight loss with rates of binge remission ranging from 55% to 75%. The two treatments did not differ significantly in weight loss or binge remission outcomes. Significant improvements were found for key dietary and metabolic outcomes, with CBT+ED producing significantly better dietary outcomes on energy density, and fruit and vegetable consumption, than CBT+GN. Reductions in energy density and weight loss were significantly associated providing evidence for the specificity of the treatment effect. These favorable outcomes, and that CBT+ED was significantly better at reducing energy density and increasing fruit and vegetable consumption compared to CBT+GN, suggest that low-energy-density dietary counseling has promise as an effective method for enhancing CBT for obese individuals with BED. [Copyright &y& Elsevier]

Background: Few studies have examined the weight-control practices that promote weight loss and weight-loss maintenance in the same sample. Purpose: To examine whether the weight control practices associated with weight loss differ from those associated with weight-loss maintenance. Methods: Cross-sectional survey of a random sample of 1165 U.S. adults. The adjusted associations of the use of 36 weight-control practices in the past week with success in weight loss (≥10% lost in the past year) and success in weight-loss maintenance (≥10% lost and maintained for ≥1 year) were examined. Results: Of the 36 practices, only 8 (22%) were associated with both weight loss and weight-loss maintenance. Overall, there was poor agreement (kappa=0.22) between the practices associated with weight loss and/or weight-loss maintenance. For example, those who reported more often following a consistent exercise routine or eating plenty of low-fat sources of protein were 1.97 (95% CI=1.33, 2.94) and 1.76 (95% CI=1.25, 2.50) times more likely, respectively, to report weight-loss maintenance but not weight loss. Alternatively, those who reported more often doing different kinds of exercises or planning meals ahead of time were 2.56 (95% CI=1.44, 4.55) and 1.68 (95% CI=1.03, 2.74) times more likely, respectively, to report weight loss but not weight-loss maintenance. Conclusions: Successful weight loss and weight-loss maintenance may require two different sets of practices. Designing interventions with this premise may inform the design of more effective weight-loss maintenance interventions. [Copyright &y& Elsevier]

Abstract: High-protein preloads have been shown to enhance satiety, but little is known about the satiating effects of protein in more typical situations when meals are consumed ad libitum. To investigate the effects of protein in amounts commonly consumed over a day, a crossover study was conducted in 2008. In this experiment, 18 normal-weight women consumed ad libitum lunch and dinner entrées 1 day a week that were covertly varied in protein content (10%, 15%, 20%, 25%, or 30% energy). Entrées were manipulated by substituting animal protein for starchy ingredients and were matched for energy density, fat content, palatability, and appearance. Unmanipulated breakfasts and evening snacks were consumed ad libitum. Participants rated their hunger and fullness before and after meals as well as the taste and appearance of entrées. Data were analyzed using a mixed linear model. Results showed that mean 24-hour protein intake increased significantly across conditions, from 44±2 g/day in the 10% protein condition to 82±6 g/day in the 30% condition. Daily energy intake did not differ significantly across the 10% to 30% protein conditions (means 1,870±93, 1,887±93, 1,848±111, 1,876±100, and 1,807±98 kcal in the 10%, 15%, 20%, 25%, and 30% energy groups, respectively). There were no significant differences in hunger and fullness ratings across conditions or in taste and appearance ratings of the manipulated entrées. This study showed that varying the protein content of several entrées consumed ad libitum did not differentially influence daily energy intake or affect ratings of satiety. [Copyright &y& Elsevier]

Abstract: Background: Strategies need to be developed to reduce preschool children’s energy intake. Objective: To test the effect of reducing the energy density of an entrée on children’s ad libitum energy intake. Subjects: Subjects were 2- to 5-year-old children (37 boys and 40 girls) in a university day-care facility. Intervention: In this within-subjects crossover study, children were served a test lunch once per week for 6 weeks. Two versions of a macaroni and cheese entrée were formulated to differ in energy density while maintaining similar palatability. Each version was served to children three times. The higher-energy-density entrée had 2.0 kcal/g and the other entrée was 30% lower in energy density. Lunch, consumed ad libitum, also included broccoli, applesauce, and milk. Main outcome measures: Food intake and energy intake were measured. Statistical analyses: A mixed linear model tested effect of energy density of the entrée on food intake and energy intake. Results are reported as mean±standard error. Results: Decreasing the energy density of the entrée by 30% significantly (P<0.0001) reduced children’s energy intake from the entrée by 25% (72.3±8.3 kcal) and total lunch energy intake by 18% (71.8±7.9 kcal). Children consumed significantly more of the lower-energy-density entrée (10.1±4.2 g; P<0.05). Children’s sex-specific body mass index–for-age percentiles did not affect the relationship between energy density of the entrée and children’s intakes. Conclusions: Decreasing the energy density of a lunch entrée resulted in a reduction in children’s energy intake from the entrée and from the total meal. Reducing the energy density of foods may be an effective strategy to moderate children’s energy intake. [Copyright &y& Elsevier]

Abstract: This study investigated how the air content of a familiar snack food affected energy intake and whether varying the method of serving the snack modified intake. We tested two versions of an extruded snack (cheese puffs) that were equal in energy density (5.7kcal/g), but differed in energy per volume (less-aerated snack: 1.00kcal/ml; more-aerated snack: 0.45kcal/ml). In a within-subjects design, 16 women and 12 men consumed the snacks ad libitum in the laboratory during four afternoon sessions. A standard volume (1250ml) of each snack was served once in a bowl and once in an opaque bag. Results showed significant differences in intake of the two snacks by energy (p=0.0003) and volume (p<0.0001); subjects consumed 21% less weight and energy (70±17kcal) of the more-aerated snack than the less-aerated snack, although they consumed a 73% greater volume of the more-aerated snack (239±24ml). These findings suggest that subjects responded to both the weight and volume of the snack. Despite differences in intake, hunger and fullness ratings did not differ across conditions. The serving method did not significantly affect intake. Results from this study indicate that incorporating air into food provides a strategy to reduce energy intake from energy-dense snacks. [Copyright &y& Elsevier]

Abstract: Objective: This study examined the impact of increasing beverage portion size on beverage and food intake. Subjects: Thirty-three subjects, 18 women and 15 men, were included. Intervention: In a crossover design, subjects consumed lunch in the laboratory once a week for 6 weeks. At each test lunch, the same foods were served, but the beverage served was varied in type (cola, diet cola, or water) and portion size (360 g/12 fl oz or 540 g/18 fl oz). Main Outcome Measures: Beverage intake (g); energy intake from foods and beverages (kcal); and ratings of hunger, satiety, and characteristics of the foods and beverages served. Results: Increasing beverage portion size significantly increased the weight of beverage consumed, regardless of the type of beverage served (P<0.05). As a consequence, for the caloric beverage, energy intake from the beverage increased by 10% for women and 26% for men when there was a 50% increase in the portion served (P<0.01). Food intake did not differ between conditions, so when the energy from the caloric beverage was added to the energy from food, total energy intake at lunch was increased significantly (P<0.001) compared with noncaloric beverages. Conclusions: Serving a larger portion of beverage resulted in increased beverage consumption, and increased energy intake from the beverage when a caloric beverage was served. Serving a caloric beverage resulted in an overall increase in total energy consumed at lunch. Therefore, replacing caloric beverages with low-calorie or noncaloric beverages can be an effective strategy for decreasing energy intake. [Copyright &y& Elsevier]

Abstract: The relative effects of energy density and palatability on energy intake, and whether there are familial influences on these effects, are not known. We investigated this issue in 7 pairs of healthy, male monozygotic twins (mean±SD age 26.3±8.6 years, BMI 23.7±3.2 kg/m2) in a clinical study involving covert ad libitum feeding of high-fat (HF, ∼40%) and low-fat (LF, ∼20%) diets in two 9-day phases. Diets were matched for average energy density, protein, fiber, and initial reported taste pleasantness, but these factors varied among the individual foods. Relationships between energy density, palatability, and energy intake were explored using regression and path analyses. Food energy density was positively associated with average taste pleasantness (r =0.46, P =0.03) independent of fat content, while energy intake from individual foods was positively associated with both energy density (r =0.56, P =0.007) and taste pleasantness (r =0.73, P <0.0001). In path analysis, both energy density and taste pleasantness directly influenced energy intake, and energy density also indirectly influenced energy intake by influencing taste pleasantness. In addition, there were significant within-twin pair similarities for the energy density–taste pleasantness and energy density–energy intake relationships (P <0.03) with the result that some twin pairs but not others identified foods high in energy density as more pleasant tasting and consumed relatively more energy from them compared to foods low in energy density. These results suggest that there are familial influences on the extent to which high energy density foods are preferred and contribute to total energy intake. [Copyright &y& Elsevier]

Abstract: Beverages are frequently consumed with meals, but their influence on meal energy intake is not understood. We hypothesized that differences in the energy, nutrient content, and sensory properties of beverages consumed with a meal would affect intake. Forty-four women ate lunch in the laboratory once a week for 6 weeks. Lunch was consumed ad libitum, and was served with one of five beverages that were consumed in full, or no beverage. The beverages were 360g of water, diet cola, regular cola, orange juice, and 1% milk. Results showed an effect of beverage type on meal intake (p&#60;0.0001). Energy intake did not differ among the non-caloric and no-beverage conditions. Similarly, energy intake from lunch (including beverage) did not differ among the caloric beverage conditions. When a caloric beverage (156kcal; 653kJ) was consumed with the meal, energy intake was 104±16kcal (435±67kJ) greater than when a non-caloric beverage or no beverage was consumed. Subjects'' ratings of fullness after lunch did not differ among the beverage conditions, but were lower for the no-beverage condition. These results show that when caloric beverages are consumed with a meal they add to energy intake from food, without significantly affecting satiety ratings. [Copyright &y& Elsevier]

The rise in obesity rates over the past 30 y has been paralleled by increases in the portion size of many foods and the prevalence of eating away from home. Foods of particular concern are those that have a high energy density (kJ/g). Many well-controlled, laboratory-based studies have found that large portions of energy dense foods can lead to excess energy intakes. This influence of large portions on energy intake has been supported by data collected in naturalistic settings. Further research is needed to explore strategies that can be used to moderate the effects of portion size on food consumption. One promising strategy is to reduce the energy density of foods, while maintaining food weight or volume, so that consumers can eat satisfying portions while reducing their energy intakes. There is a need for effective educational messages that not only emphasize limiting the consumption of foods high in energy density, but also encourage the consumption of those with a low energy density, such as fruits and vegetables. The delivery of consistent messages with require more cooperation among the food and restaurant industries, policy makers, and scientists. Effective strategies will also require consumers to understand and accept the importance of eating reasonable portions for better health. [ABSTRACT FROM AUTHOR]

As a food is consumed, its perceived pleasantness declines compared to that of other foods. This phenomenon, referred to as sensory-specific satiety, contributes to the termination of eating, along with other factors. This study tested whether the change in ratings of pleasantness after consuming a food is related to either the amount of food that is consumed or to its energy content. On each of 3 days, 36 women consumed a different formulation of a milk-based liquid food: (1) 300 ml, 2067 kJ; (2) 600 ml, 2067 kJ; or (3) 600 ml, 4134 kJ. The three formulations of the liquid food varied in volume and energy, but were matched for palatability and macronutrient composition. Participants rated the pleasantness of samples of the liquid food and four other foods both immediately before and after consumption of the liquid food. Results showed that doubling the volume of the liquid food that was consumed, without changing the energy content, significantly decreased pleasantness ratings of the liquid food and increased sensory-specific satiety. Doubling the energy content of the food without changing its volume, however, had no additional effect on the decrease in the ratings or on sensory-specific satiety. These results suggest that the volume of food that is consumed has a greater influence on perceptions of a food''s pleasantness than does its energy content. Thus, the volume of food may affect the termination of eating in part through effects on sensory-specific satiety. [Copyright &y& Elsevier]