Influence of environmental factors on food intake and choice of beverage during meals in teenagers: a laboratory study

Watching Television While Eating Increases Food Intake: A Systematic Review and Meta-Analysis of Experimental Studies

Background/Objectives: Television viewing has been linked with increased weight and obesity, likely through decreased physical activity associated with sitting and viewing television, as well as increased intake of food, likely through reduced awareness of eating and intake behaviours. This review sought to determine the effects of television viewing on energy intake relative to the absence of television. Methods: We adhered to the PRISMA guidelines and pre-registered this review in PROSPERO (CRD42023493092). The PICOS strategy included children, adolescents and adults of all ages (P), exposed to television viewing only during meals (I) compared to no television and no other distractors (C), with the outcome as energy intake or consumption (O) for both within-subject and between-subject randomised controlled trial (RCT) designs (S). Results: Robust-variance meta-analyses of k = 57 effect sizes from 23 studies showed no overall effect, noting high heterogeneity. When analyses were limited to television alone with k = 29 effect sizes from 23 studies, we revealed a small significant effect of television viewing on intake (g = 0.13, 95% CI [0.03-0.24]) compared to no television. Moderation analysis showed that television viewing strongly increased intake at the next meal (g = 0.30, 95% CI [0.03-0.57]) but not immediate intake (g = 0.10, 95% CI [-0.01-0.21]). Conclusions: This review showed that television viewing increases food intake, especially at the next meal. This effect was evident across both children and adults. This review highlights how television viewing impacts intake and offers potential avenues for intervention based on our findings.

The impact of distraction, masticatory performance and sex on food intake of school children from public and private schools: a randomized trial

Recent research highlights the influence of distraction on caloric intake in adults. This study investigated the impact of smartphone use and reading comic book on food intake of schoolchildren aged 10 to 12 years. One hundred and twenty students from public and private schools participated in experimental meal sessions. Individual parameters such as sex, age, body mass index (BMI), and eating preferences were assessed during the first session. In subsequent appointments, participants consumed standardized meals without distraction, while using a smartphone, or reading comic books in a random order. Child Three-Factor Eating Questionnaire (CTFEQr-21) was administered to assess eating behavior, and total caloric intake (kcal), total amount (g) and medium/high-energy-dense amount (g) were measured in each session. No significant difference was observed in food intake among the three experimental meals (without distractor, using smartphone and reading comic book). Masticatory performance, number of chewing cycles, and time until swallow were similar between sexes and school types (p>0.05). Regression models showed that meal duration was dependent on school type, number of teeth, time until swallow and absence of distractor, while total caloric intake was dependent on school type (public), sex (male), time until swallow, and number of cycles. Besides, total amount ingested, and medium/high-energy-dense amount were dependent on school type (public), sex (male), age, size of the particles and time until swallowing, uncontrolled eating and body mass index (p<0.05). In conclusion, the primary factors affecting food/caloric ingestion were sex, school type, and masticatory parameters, while the absence of distractor had an influence on meal duration.

Screen time and obesity prevalence in adolescents: an isotemporal substitution analysis

BACKGROUND

We examined the associations between screen time and adolescent obesity and the associations of reallocating screen time to other activities using isotemporal substitution models. Understanding the association between screen time and obesity may provide additional insights into effective obesity prevention strategies in adolescents.

METHODS

We conducted a cross-sectional analysis of 5,180 adolescents (4th and 7th grade students) from the Korean Children and Youth Panel Survey 2018. Participants reported their height, weight, and average time spent watching television, using computer, using smartphone, and other after-school activities. Obesity was defined as BMI-for-age and -sex ≥ 95th percentile based on the 2017 Korean National Growth Charts. We performed multivariable logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between screen time and obesity prevalence, adjusting for potential confounders.

RESULTS

Prolonged smartphone use (≥ 180 vs. <60 m/d: OR [95% CI] = 2.75 [2.06, 3.68]) was associated with a higher obesity prevalence. Television watching (≥ 120 vs. <60 min/d) was positively associated with obesity prevalence among 4th grade students (2.09 [1.51, 2.89]) but the association was not observed among 7th grade students (0.97 [0.63, 1.49]). One-hour increments of any non-screen time activities, with a simultaneous 1-hour decrease in combined screen time, were associated with a lower obesity prevalence (physical activity: 0.75 [0.65, 0.85]; sleeping: 0.69 [0.62, 0.78]; hanging out with friends: 0.80 [0.71, 0.89]; reading: 0.82 [0.69, 0.97]; studying: 0.84 [0.78, 0.90]; chatting with parents: 0.89 [0.88, 0.98]).

CONCLUSIONS

Our data suggest that public health strategies that reduce screen time and increase time for non-screen time activities, such as physical activity, may be effective in lowering adolescent obesity prevalence.

The effect of background music tempo on eating speed and food intake volume within in healthy women

BACKGROUND

The effects of the different tempos of background music (BGM) on food intake and eating speed have not been fully studied.

AIM

The study aimed to investigate the influence of changing the tempo of BGM during meals on food intake and to explore strategies to support appropriate eating behavior.

METHODS

Twenty-six healthy young adult women participated in this study. In the experimental phase, each participant ate a meal under three separate conditions: fast (120% speed), moderate (original, 100% speed), and slow (80% speed) BGM. The same music was used for each condition, and appetite before and after eating, the amount of food consumed, and eating speed were recorded.

RESULTS

The results showed that food intake (g, mean ± standard error (SE)) was slow: 317.9 ± 22.2, moderate: 400.7 ± 16.0, and fast: 342.9 ± 22.0. Eating speed (g/s, mean ± SE) was slow: 28.1 ± 2.8, moderate: 34.2 ± 2.7, and fast: 27.2 ± 2.4. The analysis showed that the moderate condition showed greater speed than the fast and slow conditions (slow-fast: p = .008; moderate-slow: p = .012; moderate-fast: p = .004). Moreover, the food intake in the moderate condition was significantly higher than that in the slow and fast conditions (moderate-slow: p < .001; moderate-fast: p < .001), and there was no significant difference between the slow and fast conditions in this regard (p = .077).

CONCLUSION

These results suggest that original tempo BGM led to higher food intake compared to the faster and slower tempo conditions. These findings suggest that listening to music at an original tempo during meals may support appropriate eating behavior.

Social Environment and Food and Beverage Intake in European Adolescents: The Helena Study

BACKGROUND

The family environment influences food consumption and behaviours, which impact adolescent's eating habits, diet and health. Young individuals who frequently eat family meals are less likely to develop risk- and behaviour-related outcomes as obesity.

AIM

To assess the relationship between the family meal environment and food and macronutrient consumption in European adolescents.

METHODS

1,703 adolescents aged 12.5-17.5 years (46.5% male) from the European HELENA cross-sectional study were selected. Sociodemographic variables and dietary intake using two non-consecutive self-reported 24-hour dietary recalls were collected from all the included participants. The relationship between family meals' environment and food and macronutrient consumption was analized using analysis of covariance.

RESULTS

Adolescents who used to take their main meals with their family were associated with high consumption of healthy foods and beverages (i.e. vegetables, fruit, milk, water) and low consumption of energy dense food and beverages as chocolate, savoury snacks, sugar or juices compared with those who used to eat alone, with friends or other people (p < 0.05).

CONCLUSION

The company/people with whom adolescents consume their meal have an important influence on the adolescent's consumption of different types of food (especially at lunch). Family's environment during meals has been associated with a high consumption of healthy foods.

Influence of eating with distractors on caloric intake of children and adolescents: a systematic review and meta-analysis of interventional controlled studies

Eating habits developed during childhood can be perpetuated along life and contribute to the emergence of disorders. We aimed to investigate the influence of distractors during experimental meals on the energy intake of children and adolescents. We followed the PRISMA guidelines and the study was registered in PROSPERO (CRD42021259946). The PICOS strategy consisted of children and adolescents (P), exposed to distractors during meals (I), compared with no distraction (C) and the outcome was energy intake (Kcal) (O) evaluated in crossover and parallel randomized clinical trials (RCTs) (S). Searches were conducted in PubMed, Scopus, Web of Science, Cochrane, Proquest, Embase, and LILACs databases. We employed RoB 2 tool and NutriGrade. Databases searches returned 9,576 references. Thirteen articles were selected (five crossover and eight parallel RCTs). Volunteers aged 3 to 17 years-old. All studies evaluated TV as distractor. Most studies presented high/moderate risk of bias. Meta-analysis of parallel RCT indicated no significant difference in energy intake while eating with TV (MD = 0.05; 95% CI -0.13 - 0.23, P = 0.57), with moderate certainty level. In conclusion, under laboratory conditions, eating with distractors seems to barely alter energy intake for children and adolescents.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2022.2055525 .

Perception of students on factors contributing to overweight and obesity among high school students in Kiribati: A qualitative study

BACKGROUND

Overweight and obesity among high school students is a growing distress not only to the individual wellbeing of a person but also to the productivity of communities and economic expense of both developed and developing nations. This study aimed to determine factors contributing to overweight and obesity among high school students in Kiribati through the perception of students.

METHODS

This qualitative study was conducted in four (4) randomly selected senior high schools on South Tarawa, Kiribati from August to November, 2020. A purposive sampling was used to select thirty-two (32) students enrolled into form levels 4-7. A semi-structured open-ended questionnaire was used for data collection using face-to-face in-depth interviews. Data was transcribed and analyzed using thematic analysis method.

RESULTS

This research revealed that the participants were 21 (65.6%) were females and 11 (34.4%) males from form levels four with 9 (28.1%) participants, five with 9 (28.1%) participants, and form seven with 14 (43.8%) participants. Five themes identified including determinants and prevention of overweight and obesity, education and health system factors, stigma, and being fat comes with high risk. These themes collectively elaborate on the essentials of overweight and obesity that are obtained from perspectives of students.

CONCLUSION

A strong cultural belief and practice has caused misperception of overweight and obesity among students with knowledge-behavior gap recognized as the main reason behind the failure in lifestyle changes among adolescents. Strengthen healthy behavioral lifestyle, improve awareness, and support feasible preventative strategies is recommended to all students.

A human voice, but not human visual image makes people perceive food to taste better and to eat more: "Social" facilitation of eating in a digital media

Food tastes better and people eat more when eating with others compared to eating alone. Although previous research has shown that watching television facilitates eating, the influencing factors regarding video content are unclear. We compared videos of a person speaking with those of only objects (food and a cell phone) in Experiment 1, and videos of groups of four people talking in Experiment 2. Half of these videos presented human voices (including the objects-only video), while the other half had no audio. Results showed participants rated the popcorn as tasting better and consumed more when eating alone while listening to someone talking, irrespective of whether the person was present or absent in the video in Experiment 1. A similar result was found in Experiment 2, irrespective of the increased number of people talking in the video. In Experiment 3, we assessed to what extent human voices contributed to an increase in food intake and the perceived taste of food by substituting sine-wave speech (SWS) for human voices used in Experiment 1 and found that the perceived taste of food and food intake were not facilitated when participants watched videos with SWS. The present study indicates that the human voice plays a crucial role in the perceived taste of food and consumption amount when people eat alone while watching television. Suggestions to improve food enjoyment when dining alone are discussed.

TV exposure and food consumption patterns-evidence from Indonesia

Using cross-sectional survey data from Indonesia from 2007 and 2014, this study estimates the effect of the number of available television channels during childhood on food consumption later in life with a focus on unhealthy food items. To address endogeneity of television signal strength, I exploit exogenous variations in television signal quality due to random diffractions caused by topography within a small area. Using an instrumental variables approach the results suggest that exposure to television during youth of the household head has a positive effect on household-level snack and soft drink expenditures. At the individual level I document more frequent consumption of soft drinks. Additional analysis suggests that households shift their consumption basket at the expense of vegetables and staples. Finally, heterogeneous effects analysis imply that results are driven by young individuals who are younger than 24 years old.

The social facilitation of eating: why does the mere presence of others cause an increase in energy intake?

There is strong evidence that people eat more when eating with friends and family, relative to when eating alone. This is known as the 'social facilitation of eating'. In this review, we discuss several gaps in the current scientific understanding of this phenomenon, and in doing so, highlight important areas for future research. In particular, we discuss the need for research to establish the longer-term consequences of social eating on energy balance and weight gain, and to examine whether people are aware of social facilitation effects on their own food intake. We also suggest that future research should aim to establish individual and contextual factors that moderate the social facilitation of eating (e.g. sex/gender), and it should clarify how eating socially causes people to eat more. Finally, we propose a novel evolutionary framework in which we suggest that the social facilitation of eating reflects a behavioural strategy that optimises the evolutionary fitness of individuals who share a common food resource.

The Relationship between Music and Food Intake: A Systematic Review and Meta-Analysis

Food intake has been shown to be related to several environmental factors including the presence of music. However, previous findings of the relationship between music and food intake are inconsistent. In the present study, a systematic review and meta-analysis was conducted to quantitatively review the extent to which music is associated with food intake as well as to investigate potential moderators that might have contributed to the heterogeneity of the existing findings. Literature was searched on four databases (i.e., PsycINFO, Web of Science, PubMed, and ProQuest Dissertations and Theses) and Google Scholar. Nine articles published from 1989 to 2020 met our inclusion criteria. A meta-analysis was carried out via a three-level random-effects model. The overall effect size (i.e., Hedges' g) was 0.19 (95% Confidence Interval: -0.003, 0.386; SE = 0.10, t = 1.99, p = 0.054), indicating a marginally significant but small effect size. Body Mass Index (F(1, 21) = 5.11, p = 0.035) was found to significantly contribute to the heterogeneity of effect sizes, with larger positive effects of music on food intake for individuals with higher BMI. However, music-related features did not significantly moderate the relationship between music and food intake. More experimental studies are needed to update the current meta-analysis and get a better understanding of this topic.

Gastrointestinal Contributions to the Postprandial Experience

Food ingestion induces homeostatic sensations (satiety, fullness) with a hedonic dimension (satisfaction, changes in mood) that characterize the postprandial experience. Both types of sensation are secondary to intraluminal stimuli produced by the food itself, as well as to the activity of the digestive tract. Postprandial sensations also depend on the nutrient composition of the meal and on colonic fermentation of non-absorbed residues. Gastrointestinal function and the sensitivity of the digestive tract, i.e., perception of gut stimuli, are determined by inherent individual factors, e.g., sex, and can be modulated by different conditioning mechanisms. This narrative review examines the factors that determine perception of digestive stimuli and the postprandial experience.

Exploring the Environmental Manifestation of Types of Music on Reinforcing Mindfulness and Concurrent Calorie Intake

BACKGROUND

The role of music on energy intake is conflicting, and recent research has suggested a positive association between classical music listening and mindfulness.

OBJECTIVE

The purpose of the present study was to investigate the effect of music, specifically classical music on state mindfulness and calorie intake of energy-dense foods.

METHOD

One hundred participants were randomly assigned to either a classical, popular or no music condition, and were served a variety of sweet (i.e., chocolate and cookies) and savoury (i.e., crisps) energy-dense foods. Results: The results found no significant differences in state mindfulness, overall calorie intake, or intake of sweet foods across the three conditions. However, participants in the classical music condition did consume significantly less savoury food than those in the no music condition.

CONCLUSION

Playing classical music may be beneficial in reducing intake of savoury foods, but not through the association to changes in state mindfulness. Future research should explore extended sessions of music listening on state mindfulness and other experiential evaluations of mindfulness to conclude on the direct and indirect effects of music on sweet and savoury foods.

A systematic review and meta-analysis of the social facilitation of eating

BACKGROUND

Research suggests that people tend to eat more when eating with other people, compared with when they eat alone, and this is known as the social facilitation of eating. However, little is known about when and why this phenomenon occurs.

OBJECTIVES

This review aimed to quantify the evidence for social facilitation of eating and identify moderating factors and underlying mechanisms.

METHODS

We systematically reviewed studies that used experimental and nonexperimental approaches to examine food intake/food choice as a function of the number of co-eaters. The following databases were searched during April 2019: PsychInfo, Embase, Medline, and Social Sciences Citation Index. Studies that used naturalistic techniques were narratively synthesized, and meta-analyses were conducted to synthesize results from experimental studies.

RESULTS

We reviewed 42 studies. We found strong evidence that people select and eat more when eating with friends, compared with when they eat alone [Z = 5.32; P < 0.001; standardized mean difference (SMD) = 0.76; 95% CI: 0.48, 1.03]. The meta-analysis revealed no evidence for social facilitation across studies that had examined food intake when participants ate alone or with strangers/acquaintances (Z = 1.32; P = 0.19; SMD = 0.21, 95% CI: -0.10, 0.51). There was some evidence that the social facilitation of eating is moderated by gender, weight status, and food type. However, this evidence was limited by a lack of experimental research examining the moderating effect of these factors on the social facilitation of eating among friends. In 2 studies, there was evidence that the effect of the social context on eating may be partly mediated by longer meal durations and the perceived appropriateness of eating.

CONCLUSIONS

Findings suggest that eating with others increases food intake relative to eating alone, and this is moderated by the familiarity of co-eaters. The review identifies potential mechanisms for the social facilitation of eating and highlights the need for further research to establish mediating factors. Finally, we propose a new theoretical framework in which we suggest that the social facilitation of eating has evolved as an efficient evolutionary adaptation.

Peer effects of obesity on child body composition

This study investigates whether peer obesity is a driver of individual weight changes in public school children and whether the impact of peer effects changes as children age. Quantifying peer effects is important for understanding the social determinants of obesity and for planning effective school wellness policies. However, the extant empirical research on peer effects is limited due to difficulties in separating causal influences from confounding factors. This study overcomes some of these difficulties by using a within-school, across-cohort empirical design to separate confounding factors at the individual, school and school-grade level for over one million public school children. The results show that increases a one standard deviation increase in average classmate body mass index (BMI) leads to a modest but meaningful increase of 0.395 standard deviation increase in a child's own BMI. Peer-effects are highest (0.813) for children in Kindergarten and decline with age. These findings suggest that the critical time for school-grade level intervention may be in the earliest ages of childhood development.

Socioeconomic Status in Adolescents: A Study of Its Relationship with Overweight and Obesity and Influence on Social Network Configuration

Socioeconomic status (SES) influences all the determinants of health, conditioning health throughout life. The aim of the present study was to explore the relationship between socioeconomic status and obesity in adolescence through an analysis of the patterns of contact between peers as a function of this parameter. A cross-sectional study was performed, analyzing a sample of 235 students aged 14 to 18 and 11 class networks. Social network analysis was used to analyze structural variables of centrality from a sociocentric perspective. We found that adolescents with a medium-low SES presented a two-fold higher probability of being overweight, but we did not detect any differences in the configuration of their social networks when compared with those of normal-weight adolescents. However, we did find significant differences in the formation of networks according to SES in the overall sample and disaggregated by gender, whereby adolescents with a high SES in general presented a higher capacity to form wider social networks. Elucidating the relationship between SES and overweight and its influence on social network formation can contribute to the design of preventative strategies against overweight and obesity in adolescents, since their social environment can provide them with several resources to combat excess weight.

Biogastronomy: Factors that determine the biological response to meal ingestion

BACKGROUND

The biological response to a meal includes physiological changes, primarily related to the digestive process, and a sensory experience, involving sensations related to the homeostatic control of food consumption, eg, satiety and fullness, with a hedonic dimension, ie associated with changes in digestive well-being and mood. The responses to a meal include a series of events before, during and after ingestion. While much attention has been paid to the events before and during ingestion, relatively little is known about the postprandial sensations, which are key to the gastronomical experience.

PURPOSE

The aim of this narrative review is to provide a comprehensive overview and to define the framework to investigate the factors that determine the postprandial experience. Based on a series of proof-of-concept studies and related information, we propose that the biological responses to a meal depend on the characteristics of the meal, primarily its palatability and composition, and the responsiveness of the guest, which may be influenced by multiple previous and concurrent conditioning factors. This information provides the scientific backbone to the development of personalized gastronomy.

The impact of viewing a video with and without head phones on snack intake: A pilot study

Research shows that many small changes to the environment impact one’s eating behavior. The aim of this study was to examine whether the type of audio transmission would affect snack intake depending on the degree of immersion. A sample of 174 university students were randomized to either viewing a movie wearing headphones or listening over loud speakers while consuming a snack of their choice. Significant differences were found with more snacks consumed in the group without headphones compared to the group wearing headphones. Particularly women tend to eat less (about 10% of the offered snack less) when wearing headphones while viewing a movie. The results seem to indicate that audio transmission mode might impact eating behavior.

Feasibility of a Grocery Store Tour for Parents and Their Adolescents: A Randomized Controlled Pilot Study

OBJECTIVE

To evaluate the feasibility of a grocery store tour for parents and their adolescents being led by adults or adolescent peers.

DESIGN

Randomized controlled pilot study with surveys at baseline and post-program, and at 3- and 6-month follow-up.

SETTING

Midwestern midsized grocery stores.

PARTICIPANTS

Sixty-one parents and their 71 11- to 14-year-old adolescents.

INTERVENTION

Nutrition education during 1 90-minute grocery store tour.

MAIN OUTCOME MEASURES

Process observations and participants' tour perceptions provided fidelity outcomes. Questionnaires quantitatively assessed participants' knowledge, self-efficacy, and tour strategy use.

ANALYSIS

Chi-square and McNemar tests were used to analyze categorical data, and Kruskal-Wallis, Wilcoxon signed-rank, and Mann-Whitney U tests were employed for continuous variables (significance at P < .05).

RESULTS

Over 90% of tour tasks were rated as completed well for adult and peer leaders. Participants had positive tour perceptions but noted deficiencies in teen leaders' knowledge and leadership skills. Overall, parents and adolescents retained increased self-efficacy from pre-tour to post-tour intervals. Despite limited knowledge retention, parents reported they had increased (6.5 ± 4.19) healthful grocery shopping behaviors in the 6 months after the intervention.

CONCLUSIONS AND IMPLICATIONS

Peers may feasibly lead grocery store tours but they may need additional resources and support to be highly effective.

Isotemporal Substitution Analysis for Sedentary Behavior and Body Mass Index

PURPOSE

This study examined the prospective associations of reallocating time spent in different types of sedentary behavior, physical activity, and sleep with body mass index (BMI) in children using isotemporal substitution analysis.

METHODS

Chinese children in grades 1-3 were recruited to a cohort study in 2009 and were followed up over a 2-yr period. Reports were gathered from the parents on children's sedentary behavior, sleep duration, and sociodemographic variables. The reported sedentary behavior types were then grouped into three categories: screen time (e.g., watching TV), academic-related activities (e.g., doing homework), and other sedentary behaviors (e.g., sitting and talking). Moderate-to-vigorous physical activity (MVPA) and light-intensity physical activity were assessed by ActiGraph accelerometry (ActiGraph, Pensacola, FL). Isotemporal substitution models were performed to examine the effects of time allocation on BMI.

RESULTS

A total of 672 children (359 boys, mean age at recruitment = 7.6 yr) who had provided valid accelerometer data for at least one assessment time point were included in the analysis. Controlling for covariates and total behavior time, isotemporal substitution models indicated that the displacement of 30 min·d of other sedentary behaviors with equal amounts of screen time (B = 0.12; 95% confidence interval, 0.04-0.20) or academic-related activities (B = 0.13; 95% confidence interval, 0.04-0.21) was associated with higher BMI. Reallocating 30 min·d of MVPA with each of the sedentary behavior variables resulted in increased BMI.

CONCLUSIONS

The substitution of screen time or academic-related activities with other sedentary behaviors or MVPA was associated with lower BMI in Chinese children.

Objective quantification of the food proximity effect on grapes, chocolate and cracker consumption in a Swedish high school. A temporal analysis

Close food proximity leads to increased short-term energy intake, potentially contributing to the long-term development of obesity. However, its precise effects on eating behaviour are still unclear, especially with food available for extended periods of time. This study involved two similar high school student groups (15–17 years old), which had ad libitum access to grapes, chocolates and crackers during an hour-long experimental session. In the distal condition the foods were placed 6 meters away from the students (n = 24), in contrast to the proximal condition (n = 17) were the food was placed near the students. The identification of the type and the quantification of the amount of each food selected, for each individual serving, was facilitated through use of food scales and video recording. In the proximal condition individuals served themselves grapes and crackers more often and consumed more chocolate than in the distal condition. In total, participants in the proximal condition ingested significantly more energy (726 kcal vs. 504 kcal; p = 0.029), without reporting higher fullness. Food proximity also affected the temporal distribution of servings, with the first five minutes of the sessions corresponding to 53.1% and 45.6% of the total energy intake for the distal and proximal conditions, respectively. After the first five minutes, the servings in the distal condition were strongly clustered in time, with many students getting food together. In the proximal condition however, students displayed an unstructured pattern of servings over time. In conclusion, this study strengthens past evidence regarding the important role of food proximity on individual energy intake and, for the first time, it associates continuous food proximity to the emergence of unstructured eating over time. These conclusions, expanded upon by future studies, could support the creation of meaningful intervention strategies based on spatially and temporally controlled food availability.

The effect of heightened awareness of observation on consumption of a multi-item laboratory test meal in females

Human eating behaviour is often studied in the laboratory, but whether the extent to which a participant believes that their food intake is being measured influences consumption of different meal items is unclear. Our main objective was to examine whether heightened awareness of observation of food intake affects consumption of different food items during a lunchtime meal. One hundred and fourteen female participants were randomly assigned to an experimental condition designed to heighten participant awareness of observation or a condition in which awareness of observation was lower, before consuming an ad libitum multi-item lunchtime meal in a single session study. Under conditions of heightened awareness, participants tended to eat less of an energy dense snack food (cookies) in comparison to the less aware condition. Consumption of other meal items and total energy intake were similar in the heightened awareness vs. less aware condition. Exploratory secondary analyses suggested that the effect heightened awareness had on reduced cookie consumption was dependent on weight status, as well as trait measures of dietary restraint and disinhibition, whereby only participants with overweight/obesity, high disinhibition or low restraint reduced their cookie consumption. Heightened awareness of observation may cause females to reduce their consumption of an energy dense snack food during a test meal in the laboratory and this effect may be moderated by participant individual differences.

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We examined the effect of heightened awareness of observation on food intake.

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This caused female participants to eat less of an energy dense snack food.

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This effect was moderated by weight status and trait eating behaviour measures.

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Heightened awareness of observation had little effect on intake of other foods.

Relationship between eating behaviors and physical activity of preschoolers and their peers: a systematic review

OBJECTIVES

Children learn by observing and imitating others, meaning that their eating behaviors and physical activity may be influenced by their peers. This paper systematically reviews how preschoolers' eating behaviors and physical activity relate to their peers' behaviors, and discusses avenues for future research.

METHODS

Six databases were searched for quantitative, peer-reviewed studies published up to July 2015 reporting on the correlates, predictors or effectiveness of peers on eating behaviors and physical activity in preschoolers. Risk of bias was independently assessed by two evaluators using the Quality Assessment Tool for Quantitative Studies.

RESULTS

Thirteen articles were included: six measured physical activity, and seven assessed eating behaviors. Four of the six physical activity studies reported that children were more active when peers were present, while large peer group size was negatively associated with physical activity in two cross-sectional studies. All nutrition interventions reported that children's eating behaviors may be influenced by their peers.

CONCLUSIONS

Although supported by weak evidence, peers appear to influence children's eating behaviors and physical activity. However, this influence may be moderated by the number of peers, gender, age and the perceived status of the role models. Future obesity prevention interventions should consider involving peers as agents for positive eating behaviors and physical activity in preschoolers.

Television and eating: repetition enhances food intake

Some studies find that eating with TV increases food intake while others do not. Some of this variability may reflect the engagingness of what is being watched (i.e., content). To test this we varied engagingness by manipulating content familiarity. Female participants undertook two sessions. In the “Different” session they watched two different episodes of the comedy Friends, with snack food presented during the second episode. In the “Same” session they viewed another episode of Friends twice in succession, with snack food presented during the second repeat showing. The three episodes of Friends used here were fully counterbalanced, so overall the only difference between the “Same” and “Different” sessions was whether the content of the second show was familiar or novel. As expected, 14% less was eaten in the “Different” session, suggesting that novel and presumably more engaging content can reduce intake relative to watching familiar and presumably less engaging content. These findings are consistent with the idea that the engagingness of TV can differentially affect food intake, although boredom or irritability resulting from repeat viewing might also explain this effect.

The social facilitation of eating. A review

The social facilitation of eating (i.e., people eating more in groups than when alone) has been studied for about three decades now. In this paper, we review the empirical research (diary studies, observational studies, and experimental studies) of social facilitation, attending to factors that increase or decrease socially facilitated eating. We also review the various explanations (e.g., "time extension") that have been offered for the effect and offer our own speculations as to the underlying mechanisms. Further, we discuss promising directions for future research on the social facilitation of eating.

Watching TV and food intake: the role of content

Obesity is a serious and growing health concern worldwide. Watching television (TV) represents a condition during which many habitually eat, irrespective of hunger level. However, as of yet, little is known about how the content of television programs being watched differentially impacts concurrent eating behavior. In this study, eighteen normal-weight female students participated in three counter-balanced experimental conditions, including a ‘Boring’ TV condition (art lecture), an ‘Engaging’ TV condition (Swedish TV comedy series), and a no TV control condition during which participants read (a text on insects living in Sweden). Throughout each condition participants had access to both high-calorie (M&Ms) and low-calorie (grapes) snacks. We found that, relative to the Engaging TV condition, Boring TV encouraged excessive eating (+52% g, P = 0.009). Additionally, the Engaging TV condition actually resulted in significantly less concurrent intake relative to the control ‘Text’ condition (−35% g, P = 0.05). This intake was driven almost entirely by the healthy snack, grapes; however, this interaction did not reach significance (P = 0.07). Finally, there was a significant correlation between how bored participants were across all conditions, and their concurrent food intake (beta = 0.317, P = 0.02). Intake as measured by kcals was similarly patterned but did not reach significance. These results suggest that, for women, different TV programs elicit different levels of concurrent food intake, and that the degree to which a program is engaging (or alternately, boring) is related to that intake. Additionally, they suggest that emotional content (e.g. boring vs. engaging) may be more associated than modality (e.g. TV vs. text) with concurrent intake.

Peers and Obesity during Childhood and Adolescence: A Review of the Empirical Research on Peers, Eating, and Physical Activity

Obesity during childhood and adolescence is a growing problem in the United States, Canada, and around the world that leads to significant physical, psychological, and social impairment. In recent years, empirical research on factors that contribute to the development and maintenance of obesity has begun to consider peer experiences, such as peer rejection, peer victimization, and friendship. Peer experiences have been theoretically and empirically related to the “Big Two” contributors to the obesity epidemic, eating and physical activity, but there has not been a comprehensive review of the extant empirical literature. In this article, we review and synthesize the emerging theoretical and empirical literatures on peer experiences in relation to: (a) eating (food consumption and food selection); and (b) physical activity, during childhood and adolescence. A number of limitations and issues in the theoretical and empirical literatures are also discussed, along with future research directions. In conclusion, we argue that the involvement of children and adolescents’ peer networks in prevention and intervention efforts may be critical for promoting and maintaining positive behavioral health trajectories.

Decreasing sugar-sweetened beverage consumption in the rural adolescent population

Adolescent consumption of sugar-sweetened beverages (SSBs) has increased drastically with detrimental effects such as weight gain, weakened bones, dental caries, and associated higher levels of type II diabetes in this population. While in the clinical setting, rural family nurse practitioner (FNP) students, using Kellogg-funded Smart Phones, screened adolescents aged 13 to 17 years for SSB consumption in the previous 24 hours. Adolescents initially were provided with a pamphlet and related oral teaching concerning SSBs by the FNP students, as well as a water bottle to encourage healthy fluid intake. Screening SSB information was loaded onto Smart Phones, which resulted in immediate access by the primary investigator sometimes even hundreds of miles distant. After 30 days, FNP students completed follow-up phone interviews to reassess SSB consumption in the previous 24 hours. Results concerning decreased SSB consumption were statistically significant. Additionally, Smart Phones were instrumental in high-speed data transfer. Both advantages and disadvantages were encountered when using this evolving technology.

The non-advertising effects of screen-based sedentary activities on acute eating behaviours in children, adolescents, and young adults. A systematic review

Sedentary screen time may be an important determinant of childhood obesity. A number of potential mechanisms to explain the link between screen time and increased bodyweight have been proposed; however, the relationship appears to be best explained by the effects on dietary intake, which is attributed to either food advertising or effects independent of food advertising. Technological advances have allowed for greater accessibility and exposure to advertisement-free screen-based media. This review was conducted to systematically synthesise the evidence from laboratory based studies which have investigated the non-advertising effects of screen time (TV viewing, sedentary video games, and computer use) on dietary intake in children, adolescents, and young adults. MEDLINE, PubMed, PsychInfo, CINAHL, and Embase were searched from inception through 5 July 2013. Ten trials met the inclusion criteria and were included in the review. Risk of study bias was judged to range from low to high. Screen time in the absence of food advertising was consistently found to be associated with increased dietary intake compared with non-screen behaviours. Suggested explanations for this relationship included: distraction, interruption of physiologic food regulation, screen time as a conditioned cue to eat, disruption of memory formation, and the effects of the stress-induced reward system. Due to the limited number of high-quality studies available for this review, our findings are preliminary. More work is required to better establish the link between dietary intake and advertisement-free screen time and assess whether differences exist between the different screen-based activities.

Young children's screen habits are associated with consumption of sweetened beverages independently of parental norms

OBJECTIVES

This study investigated the associations between children's screen habits and their consumption of sweetened beverages. Because parents might be disposed to regulate their child's screen and dietary habits in a similar direction, our specific aim was to examine whether these associations were independent of parental norms.

METHODS

In the Swedish sample of the European Identification and prevention of dietary and lifestyle-induced health effects in children and infants (IDEFICS) study, parents filled in questionnaires about their 2 to 9-year-old children's (n = 1,733) lifestyle and diets.

RESULTS

Associations between screen habits and sweetened beverage consumption were found independent of parental norms regarding sweetened beverages. A longitudinal analysis revealed that sweetened beverage consumption at 2-year follow-up was predicted by exposure to commercial TV at baseline (OR 1.4, 95 % CI 1.1-1.9). Cross-sectional analysis showed that the likelihood of consuming sweetened beverages at least 1-3 times per week increased for each hour/day watching television (OR 1.5, 95 % CI 1.2-1.9), and for being exposed to commercials (OR 1.6, 95 % CI 1.3-2.1). TV viewing time and commercial exposure contributed to the associations independently of each other.

CONCLUSIONS

The results strengthen the assumption that it is possible to influence children's dietary habits through their TV habits.

Lifestyle determinants of the drive to eat: a meta-analysis

BACKGROUND

Obesity is emerging as the most significant health concern of the 21st century. Although this is attributable in part to changes in our environment-including the increased prevalence of energy-dense food-it also appears that several lifestyle factors may increase our vulnerability to this calorie-rich landscape. Epidemiologic studies have begun to show links between adiposity and behaviors such as television watching, alcohol intake, and sleep deprivation. However, these studies leave unclear the direction of this association. In addition, studies that investigated the acute impact of these factors on food intake have reported a wide variety of effect sizes, from highly positive to slightly negative.

OBJECTIVE

The purpose of this article was to provide a meta-analysis of the relation between lifestyle choices and increases in acute food intake.

DESIGN

An initial search was performed on PubMed to collect articles relating television watching, sleep deprivation, and alcohol consumption to food intake. Only articles published before February 2012 were considered. Studies that took place in a controlled, laboratory setting with healthy individuals were included. Studies were analyzed by using 3 meta-analyses with random-effects models. In addition, a 1-factor ANOVA was run to discover any main effect of lifestyle.

RESULTS

The 3 most prominent lifestyle factors-television watching, alcohol intake, and sleep deprivation-had significant short-term effects on food intake, with alcohol being more significant (Cohen's d = 1.03) than sleep deprivation (Cohen's d = 0.49) and television watching (Cohen's d = 0.2).

CONCLUSIONS

Our results suggest that television watching, alcohol intake, and sleep deprivation are not merely correlated with obesity but likely contribute to it by encouraging excessive eating. Because these behaviors are all known to affect cognitive functions involved in reward saliency and inhibitory control, it may be that they represent common mechanisms through which this eating is facilitated.

Associations of television viewing with eating behaviors in the 2009 Health Behaviour in School-aged Children Study

OBJECTIVE

To examine associations of television viewing with eating behaviors in a representative sample of US adolescents.

DESIGN

Cross-sectional survey.

SETTING

Public and private schools in the United States during the 2009-2010 school year.

PARTICIPANTS

A total of 12,642 students in grades 5 to 10 (mean [SD] age, 13.4 [0.09] years; 86.5% participation).

MAIN EXPOSURES

Television viewing (hours per day) and snacking while watching television (days per week).

MAIN OUTCOME MEASURES

Eating (≥1 instance per day) fruit, vegetables, sweets, and sugary soft drinks; eating at a fast food restaurant (≥1 d/wk); and skipping breakfast (≥1 d/wk).

RESULTS

Television viewing was inversely related to intake of fruit (adjusted odds ratio, 0.92; 95% CI, 0.88-0.96) and vegetables (0.95; 0.91-1.00) and positively related to intake of candy (1.18; 1.14-1.23) and fast food (1.14; 1.09-1.19) and skipping breakfast (1.06; 1.02-1.10) after adjustment for socioeconomic factors, computer use, and physical activity. Television snacking was related to increased intake of fruit (adjusted odds ratio, 1.06; 95% CI, 1.02-1.10), candy (1.20; 1.16-1.24), soda (1.15; 1.11-1.18), and fast food (1.09; 1.06-1.13), independent of television viewing. The relationships of television viewing with fruit and vegetable intake and with skipping breakfast were essentially unchanged after adjustment for television snacking; the relationships with intake of candy, soda, and fast food were moderately attenuated. Age and race/ethnicity modified relationships of television viewing with soda and fast food intake and with skipping breakfast.

CONCLUSION

Television viewing was associated with a cluster of unhealthy eating behaviors in US adolescents after adjustment for socioeconomic and behavioral covariates.

Influence of peers and friends on children's and adolescents' eating and activity behaviors

Obesity during childhood and adolescence is a growing problem in the United States, Canada, and around the world that leads to significant physical, psychological, and social consequences. Peer experiences have been theoretically and empirically related to the "Big Two" contributors to the obesity epidemic, unhealthy eating and physical inactivity. In this article, we synthesize the empirical literature on the influence of peers and friends on youth's eating and physical activity. Limitations and issues in the theoretical and empirical literatures are also discussed, along with future research directions. In conclusion, we argue that the involvement of children's and adolescents' peer networks in prevention and intervention efforts may be critical for promoting and maintaining positive behavioral health trajectories. However, further theoretical and empirical work is needed to better understand the specific mechanisms underlying the effects of peers on youth's eating and physical activity.

Television viewing at mealtime reduces caloric compensation in peripubertal, but not postpubertal, girls

The effect of television viewing (TVV) and pubertal status of 9- to 14-y-old girls on mealtime food intake (FI) after a premeal glucose drink was determined. On four separate mornings, girls randomly received equally sweetened drinks containing Sucralose (control) or glucose (1.0 g/kg body weight) in 250 mL of water 2 h after a standardized breakfast. FI from an ad libitum pizza meal was measured 30 min later with or without TVV. Appetite was measured at 15 min intervals to lunch and postmeal. TVV at mealtime had no effect on FI, however, glucose suppressed FI more with no TVV compared with TVV (24 versus 10%, p < 0.001), primarily because of its effect in peripubertal girls (p < 0.028). In postpubertal girls (n = 8), glucose reduced FI by ~27% in both the no TVV and TVV conditions, but in peripubertal girls (n = 17), reduction in FI was 22% without TVV and only 1% while TVV. Appetite correlated with FI at 30 min only in postpubertal girls. TVV at mealtime reduced caloric compensation after consumption of the glucose drink in peripubertal, but not postpubertal, girls, with no effect on mealtime FI. (Clinical trial number NCT01025687.)