Barbara Jean Rolls

Pennsylvania State University | Penn State · Department of Nutritional Sciences

Processed foods have been part of the American diet for decades, with key roles in providing a safe, available, affordable, and nutritious food supply. The USDA Food Guides beginning in 1916 and the US Dietary Guidelines for Americans (DGA) since 1980 have included various types of commonly consumed processed foods (e.g., heated, fermented, dried)...

The neural mechanisms underlying susceptibility to eating more in response to large portions (i.e., the portion size effect) remain unclear. Thus, the present study examined how neural responses to portion size relate to changes in weight and energy consumed as portions increase. Associations were examined across brain regions traditionally implica...

Introduction: Recently published studies support the beneficial effects of consuming fibre-rich legumes, such as cooked dry beans, to improve metabolic health and reduce cancer risk. In participants with overweight/obesity and a history of colorectal polyps, the Fibre-rich Foods to Treat Obesity and Prevent Colon Cancer randomised clinical trial w...

A crucial step for validating the utility of an immersive virtual reality (iVR) buffet to study eating behavior is to determine whether variations in food characteristics such as portion size (PS) are relevant predictors of food selection in an iVR buffet. We tested whether manipulating PS in an iVR buffet affects the weight of food selected, and w...

Objective The objective of this study was to determine whether children with healthy weight who vary by familial risk for obesity differ in executive functioning. Methods Children (age 7–8 years) without obesity ( n = 93, 52% male) who differed by familial risk for obesity (based on maternal weight status) completed go/no‐go and stop‐signal tasks...

Context: Reward-based eating is a trait that increases risk for eating in the absence of hunger (EAH) and obesity. Eating behaviors such as switching more frequently between different foods may increase intake during EAH by delaying the onset of sensory-specific satiation (SSS); however, this question has not been empirically tested. Objectives:...

Objective: The aim of this study was to evaluate whether dimensions of sleep quality were associated with homeostatic and hedonic eating behaviors among children with healthy weight (BMI-for-age < 90%) but varying maternal weight status. Methods: A total of 77 children (mean [SD], age: 7.4 [0.6] years; BMI z score: -0.10 [0.7]) with healthy weig...

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...

It is recommended that preschoolers serve themselves their own food portions; however, it is unclear what factors influence the amount they select for consumption, and particularly how their selected portions are influenced by food properties such as energy density, volume, and weight. We offered preschool children snacks differing in energy densit...

Background: Since children often consume substantial proportions of their diets in childcare programs, it is critical to determine what they eat when served menus meeting dietary recommendations and how intake is related to individual characteristics. Objectives: Using weighed assessments, we characterized children's consumption across 15 daily...

Individuals eat more when served more food, but little is known about how this portion size effect is moderated by meal-related characteristics, particularly the inclusion of water served as a beverage. Patterns of eating and drinking as well as consumption of water could affect satiation by modifying exposure to the sensory qualities of food. In a...

Serving larger portions leads to increased food intake, but behavioral factors that influence the magnitude of this portion size effect have not been well characterized. We investigated whether measures of eating microstructure such as eating rate and bite size moderated the portion size effect. We also explored how sensory-specific satiety (SSS; t...

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 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 related to mea...

Increasing childhood obesity rates in both the United States and worldwide demonstrate a need for better prevention and intervention strategies. However, little is understood about what factors influence children's ability to sense and respond to hunger and fullness cues, a critical component of self-regulation of energy intake and maintenance of a...

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...

Food variety, complexity, and portion size each influence food choice and consumption, but their relative importance is poorly understood. In an online discrete choice-experiment, we investigated the relative importance of variety, complexity, and portion size in consumer preferences by systematically varying ice cream offerings. Complexity was def...

Consumers vary in the explanations they give for meal termination. The Reasons Individuals Stop Eating Questionnaire (RISE-Q) was developed to measure these satiation processes. Individual differences in satiation may be associated with a general capacity to recognise and respond to contextual and interoceptive cues. The aims of the present study w...

Background Although dietary guidelines recommend that vegetables and fruits make up half the diet, it is unclear whether serving vegetables and fruits in larger portions will have sustained effects on children's intake over multiple days. Objective This study tested the effects on children's intake of 2 strategies for increasing the proportion of...

Objectives Food liking influences food choice and the most-liked foods are often energy dense. Previous studies found that both food liking and energy density predicted the size of portions selected by adults. To extend these findings, we investigated the independent and combined effects of food liking and energy density on portion selection in chi...

Objectives Although current guidelines recommend that vegetables and fruits make up half the diet, it is not known whether serving a greater proportion of vegetables and fruits will have sustained effects on children's consumption over multiple days. This study tested the effects on children's intake of two strategies for increasing the proportion...

Objectives The relationship between parentally reported satiety responsiveness (i.e., trait) and laboratory-assessed satiety responsiveness (i.e., state) in children is not known, making it difficult to interpret and generalize lab-based findings. In addition, while many studies have shown weight-related differences in children's eating behaviors,...

Objectives Individuals eat more when served larger portions, and this may be influenced by eating-related microstructural behaviors. In a controlled study, we explored whether microstructural components of eating such as eating rate, bite size, bite count, and meal duration influenced the portion size effect. Methods In a randomized crossover desi...

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 understandin...

This study investigated the independent and combined effects on preschool children’s vegetable intake of serving a larger portion of vegetables and enhancing their flavor. In a crossover design, lunch was served in childcare centers once a week for four weeks to 67 children aged 3-5 y (26 boys, 41 girls). The meal consisted of two familiar vegetabl...

A variety of factors can influence satiation, and individual differences in reasons for meal termination may help to explain variability in food intake and susceptibility to overconsumption. We developed and validated a questionnaire to characterize the Reasons Individuals Stop Eating (RISE-Q). The initial RISE-Q was created by reviewing the publis...

Determinants of food choice are broad and include policies, prices, settings and context, as well as interpersonal factors, such as family, cultural, and peer effects. This review focuses more narrowly on food choices at the individual level by providing an overview of various methods and tools that have been used to understand psychological, cogni...

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 th...

Food images are routinely used to investigate the cognitive and neurobiological mechanisms of eating behaviors, but there is a lack of standardized image sets for use in children, which limits cross-study comparisons. To address this gap, we developed a set of age-appropriate images that included 30 high-energy-dense (ED) foods (>2.00 kcal/g), 30 l...

Objectives To meet dietary guidelines, effective strategies are needed to encourage children to eat a greater proportion of their diet from vegetables. We tested whether serving a larger portion, enhancing the taste with small amounts of butter and salt, or combining these strategies would increase vegetable intake at a meal for preschool children....

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 r...

Because no validated tool exists to assess nutrition knowledge regarding weight management we developed and tested the Weight Management Nutrition Knowledge Questionnaire (WMNKQ). The questionnaire assesses nutrition knowledge in these categories: energy density of food, portion size/serving size, alcohol and sugar sweetened beverages, how food var...

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 obes...

Environmental cues, such as the colour of food and dishware, have been shown to influence food and drink consumption in adult populations. This proof of concept study investigated whether plate colour could be utilised as a strategy to reduce intake of high energy density (HED) snacks and increase intake of low energy density (LED) snacks in pre-sc...

Objective: Adolescents and young adults select larger portions of energy-dense food than recommended. The majority of young people have a social media profile, and peer influence on social media may moderate the size of portions selected. Methods: Two pilot interventions examined whether exposure to images of peers' portions of high-energy-dense...

Abstract Objective: To test whether adding herbs and spices to school lunch vegetables increases selection and intake compared to lightly salted control versions among rural adolescents. Design: This study compared intake of vegetables with herbs and spices to lightly salted control (phase I) and tested whether 5 repeated exposures would increase...

Background: Although short-term studies have found that serving larger portions of food increases intake in preschool children, it is unknown whether this portion size effect persists over a longer period or whether energy intake is moderated through self-regulation. Objectives: We tested whether the portion size effect is sustained in preschool...

Background and objective: To investigate preschool children's ability to self-regulate their energy intake, we assessed their response to increases or decreases in dietary energy density (ED) over 5 consecutive days, a period likely long enough for compensatory behavior. Methods: Using a crossover design, over 3 periods we served the same 5 dail...

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 o...

Abstract Objective: Adolescents and young adults select larger portions of energy-dense food than recommended. The majority of young people have a social media profile, and peer influence on social media may moderate the size of portions selected. Methods: Two pilot-interventions examined whether exposure to images of peers’ portions of high-energ...

Large portions of energy dense foods promote overconsumption but offering small portions might lead to compensatory intake of other foods. Offering a variety of vegetables could help promote vegetable intake and offset the effect of reducing the portion size (PS) of a high energy dense (HED) food. Therefore, we tested the effect on intake of reduci...

Large portions of high energy dense (HED) snacks are offered to children from a young age and are pervasive in our food environment. This study aimed to explore the feasibility, acceptability, and preliminary efficacy of two strategies of snack portion control: reduction and replacement. Forty-six mother-child dyads aged 22–56 months (36.6 ± 9.5 m,...

Public-private partnerships are an effective way to address the global double burden of malnutrition. While public-private partnerships operate in multiple forms, their leadership usually falls to governments, public health agencies, or nongovernmental organizations, with the private sector taking a subordinate role. The rapid ascent of social medi...

Objective The Diet Satisfaction Questionnaire was developed to fill the need for a validated measure to evaluate satisfaction with weight‐management diets. This paper further develops the questionnaire, examining the factor structure of the original questionnaire, cross‐validating a revised version in a second sample, and relating diet satisfaction...

Background Portion size influences intake (i.e. the portion size effect [PSE]), yet determinants of susceptibility to the PSE are unclear. Objective We tested whether children who reported an episode of loss of control (LOC) eating over the last 3 months would be more susceptible to the PSE and would show differential brain responses to food cues...

Serving larger portions leads to increased food and energy intake, but little is known about strategies to moderate this response. This study tested how the effect of portion size on meal intake was influenced by providing the option to take away uneaten food in a "doggy bag" (to-go container). Women were randomly assigned to one of two subject gro...

Background: High gestational weight gain is a major public health concern as it independently predicts adverse maternal and infant outcomes. Past interventions have had only limited success in effectively managing pregnancy weight gain, especially among women with overweight and obesity. Well-designed interventions are needed that take an individu...

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" (Hether...

Serving larger portions leads to increased intake, but little is known about how the cost of a meal affects this response. Therefore, we tested whether the amount of money paid for a meal influenced the portion size effect at a lunch served in a controlled restaurant-style setting. In a crossover design, 79 adults (55 women; 24 men) came to the lab...

Offering large portions of high-energy-dense (HED) foods increases overall intake in children and adults. This is known as the portion size effect (PSE). It is robust, reliable and enduring. Over time, the PSE may facilitate overeating and ultimately positive energy balance. Therefore, it is important to understand what drives the PSE and what migh...

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 b...

Large portions promote intake of energy dense foods (i.e., the portion size effect--PSE), but the neurobiological drivers of this effect are not known. We tested the association between blood oxygen level dependent (BOLD) brain response to food images varied by portion size (PS) and energy density (ED) and children's intake at test-meals of high- a...

Purpose: Vegetable consumption in youth is below recommendations and strategies to increase intake at school are needed. We investigated barriers to vegetable intake at a rural public high school and evaluated whether new vegetable recipes using herbs and spices would increase liking and preference for vegetables served to adolescents at this schoo...

Following a 1-year randomized controlled trial that tested how weight loss was influenced by different targeted strategies for managing food portions, we evaluated whether the effect of portion size on intake in a controlled setting was attenuated in trained participants compared to untrained controls. Subjects were 3 groups of women: 39 participan...

Several dietary patterns, both macronutrient and food based, can lead to weight loss. A key strategy for weight management that can be applied across dietary patterns is to reduce energy density. Clinical trials show that reducing energy density is effective for weight loss and weight loss maintenance. A variety of practical strategies and tools ca...

Objective Identifying early predictors of weight loss is key for developing personalized treatment. However, few individual factors have been identified that predict weight loss during intervention, other than early weight loss itself. Methods Women with overweight or obesity (n = 186, mean ± SD age 50.0 ± 10.6 years, body mass index 34.0 ± 4.2 kg...

Studies conducted by behavioural scientists show that the energy density (kcal/g) of food provides effective guidance for healthy food choices to control intake and promote satiety. Energy density depends upon a number of dietary components, especially water (0 kcal/g) and fat (9 kcal/g). Increasing the proportion of water or water-rich ingredients...

Objective: During a one-year weight loss trial, we compared the Three-Factor Eating Questionnaire (TFEQ), a valid 51-item measure of restraint, disinhibition, and hunger subscales, with the newer 16-item Weight-Related Eating Questionnaire (WREQ) measuring routine and compensatory restraint and external and emotional eating. Methods: Both questi...

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 one-year randomized trial, we tested whether the efficacy of a behavioral weight-loss program was improved by incorporating either of two portion-control strategies instead...

Background: Large portions of food promote intake, but the mechanisms that drive this effect are unclear. Previous neuroimaging studies have identified the brain-reward and decision-making systems that are involved in the response to the energy density (ED) (kilocalories per gram) of foods, but few studies have examined the brain response to the f...

Objective: Binge eating disorder (BED) is strongly associated with obesity and related medical and psychiatric morbidities. Cognitive behavioral therapy (CBT) has consistently been shown to reduce binge eating frequency and improve psychological functioning, as well as to produce abstinence rates of roughly 50%. This study examined the relationshi...

Objective: Large portions of energy-dense foods drive energy intake but the brain mechanisms underlying this effect are not clear. Our main objective was to investigate brain function in response to food images varied by portion size (PS) and energy density (ED) in children using functional magnetic resonance imaging (fMRI). Methods & design: Bl...