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

Potatoes Compared with Rice in Meals with either Animal or Plant Protein Reduce Postprandial Glycemia and Increase Satiety in Healthy Adults: A Randomized Crossover Study

BACKGROUND

Rice and pasta are recommended as healthier than potatoes on the basis of their glycemic index when eaten alone.

OBJECTIVES

The study objective was to evaluate postprandial glycemia (PPG), appetite, and food intake (FI) at meals with potatoes or rice when consumed with either meatballs or their vegetarian substitute.

METHODS

In a randomized, single-blinded, crossover design, 26 (13 males and 13 females) healthy adults (age: 18-45 y; body mass index [kg/m2]: 18.5-29.9) consumed isocaloric fixed amounts of either meatballs or vegetarian-substitute balls with ad libitum access to either baked French fries (BFF), instant mashed potatoes (IMPs), or rice (control). FI was measured at the meal and at an ad libitum pizza meal served 120 min later. Blood glucose (BG), appetite, and plasma insulin responses were measured within the meal (0-30 min), postmeal (30-120 min), within pizza meal (120-140 min), and post-pizza (140-170 min). Effects of protein source, carbohydrate (CHO) source, and sex and their interactions were analyzed using analysis of variance followed by Tukey's post hoc test.

RESULTS

Participants consumed 23-25% less treatment meal energy (kcal), 32-34% less CHO energy (kcal), and 13-16% less total energy (kcal) after the BFF and IMP than rice meals (P < 0.0001). Postmeal BG was lower after IMP (6.76 ± 0.15; P < 0.0001) and rice (6.92 ± 0.15; P = 0.0012) compared with BFF (7.19 ± 0.15). Post-pizza BG was higher after rice (6.77 ± 0.09) than that after BFF (6.51 ± 0.09; P = 0.0012) and IMP (6.39 ± 0.09; P < 0.0001). Postmeal meaned insulin was higher after BFF (82.16 ± 8.58) and IMP (77.75 ± 8.60) compared with rice (56.44 ± 8.59; P < 0.002). Insulin during pizza meal was lower after BFF (17.14 ± 6.90) compared with both IMP (39.03 ± 6.90; P = 0.0060) and rice (34.21 ± 6.90; P = 0.0336). Meatballs led to lower BG (6.48 ± 0.09; P = 0.0076) and higher insulin (84.54 ± 5.87; P = 0.0406) post-pizza compared with their plant protein substitute (6.64 ± 0.09 and 73.18 ± 5.87, respectively).

CONCLUSIONS

Adults consuming meatballs or plant-based substitute with ad libitum IMP had lower PPG post-treatment and at a later pizza meal compared with rice. Both IMP and BFF resulted in lower energy intake than after rice. This trial was registered at http://clinicaltrials.gov (https://register.

CLINICALTRIALS

gov/prs/app/action/SelectProtocol?sid=S000CKIJ&selectaction=Edit&uid=U0000IA4&ts=2&cx=-uf51kf) as NCT05610124. Protocol ID: 43406 (Postprandial Glycemia and Satiety of Meals with Potatoes, with and without Protein).

Inter-individual differences in children's short-term energy compensation: a systematic review and meta-analysis

BACKGROUND

The ability to regulate energy intake is often assessed using a preloading paradigm to measure short-term energy compensation. In children, large variability exists with this paradigm both within- and across- studies and is poorly understood.

OBJECTIVES

This systematic review and meta-analysis aimed to better understand factors contributing to variability in children's energy compensation. We tested 1) whether children demonstrated "good" energy compensation, defined as adjusting meal intake commensurate with preload intake and 2) differences in children's energy compensation by child age, sex, and weight status (assessed both continuously and categorically).

METHODS

Standard guidelines for systematic review were followed to search PubMed, PsychInfo, and Web of Science. Data on study design (preload form, preload-to-meal interval, preload energy difference, study setting) and participant characteristics (sex, age, weight status) were extracted from 29 experiments meeting inclusion criteria, and 13 were included in meta-analyses. COMPx (energy compensation index), a linear transformation comparing food intake following a high- vs. low-energy preload, was the outcome. Hedge's g was calculated, and random intercept-only models tested associations between COMPx and sex, age, and weight status.

RESULTS

The systematic review revealed mixed results regarding children's energy compensation and the role of inter-individual differences. Meta-analytic models revealed that children undercompensated (overate) for preload energy (β = -0.38; P = 0.008). Sex (β = 0.11; P = 0.76), age (β = 0.03; P = 0.75), and weight (assessed continuously; β = -0.07, P = 0.37) were not related to compensation. Children with overweight/obesity (assessed categorically) undercompensated more than children with healthy weight (β = 0.18; P = 0.04).

CONCLUSIONS

The systematic review highlighted wide variability across studies, while the meta-analysis demonstrated differences in COMPx by child weight status but not by age or sex. Standardizing protocols across studies is recommended, along with designing adequately powered studies aiming to test inter-individual differences a priori. Alternative approaches to the use of COMPx are recommended to allow better characterization of children's energy compensation ability. This study was registered at PROSPERO as CRD42020197748.

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 .

Screen use during food consumption: Does it cause increased food intake? A systematic review

Nowadays people use screens, such as mobile phones, television, or tablets, more often during mealtimes, which may have an effect on intake. This review aims to analyze the effect of screen use, during food consumption, on intake. A systematic review was carried out, based on those protocols established by PRISMA. The Cochrane Library, PubMed, Web of Science and Scopus databases were consulted. Experimental studies, published between 2010 and 2021, that recorded individual intake while using screens such as television, cell phones, or tablets, were selected. A total of 7181 relevant articles were obtained, which were then assessed in accordance with predetermined inclusion and exclusion criteria. Finally, 35 studies were included in the complete review: 22 compared different kinds of television content (e.g., adverts), five which compared television versus the absence of screens, four which compared television versus video games, two which compared the use of simultaneous screens, and two studies which included cell phones. A total of 27 studies reported consumption increases related to the presence of advertisements and food signals on screens. No significant differences in intake were reported in the eight studies that reported design or sample size limitations, or lack of control of certain variables. It is thus concluded that screen use during food consumption may increase intake. Education is necessary to regulate the habit of consuming food in the presence of screens. Also, the creation of policies that regulate advertising and food cues on screens are justified and must be accompanied by strategies to monitor compliance. As a limitation, further evidence is necessary in order to determine the effect of mobile phone and tablet use while eating. This protocol was registered via PROSPERO, ID: CRD42020211797.

Using Smartphones When Eating Increases Caloric Intake in Young People: An Overview of the Literature

Recent literature highlights that the use of smartphones during meals increases the number of calories ingested in young people. Although the distraction interferes with physiological signals of hunger and satiety, a social facilitation effect has also been suggested. Cognition is a pivotal component in regulating food intake, and activities requiring high perceptual demands should be discouraged during meals.

Oral Health and Nutritional Characteristics of Adults With Morbid Obesity: A Multivariate Analysis

The relationship between oral health and nutritional aspects are complex, especially in individuals with chronic diseases and comorbidities, such as morbid obesity. Thus, the aim of the present study was to identify oral health and nutritional-related patterns in 113 individuals, aged 19–68 years (92 females), seeking treatment for morbid obesity. Sociodemographic variables and medical records were examined, in addition to the consumption of fruit, vegetables, candies, and processed foods. Measures of body mass index, neck, waist and hip, caries experience (DMFT index), Community Periodontal Index (CPI index), and salivary physicochemical aspects were gathered. Aspects of oral health-related quality of life and symptoms of dry mouth were evaluated by means of Oral Health Impact Profile (OHIP-14) and Xerostomia Inventory-XI questionnaires. K-means cluster analysis and, subsequently, comparisons between clusters (one-way ANOVA) were performed (α = 5%). Three clusters were generated: Cluster 1 (labeled “Young”; n = 77) was characterized by younger participants with higher BMI, who reported the use of distractors while eating, the smallest number of meals/day, and who consumed sweetened drinks and processed food the day before. Cluster 2 (labeled “Diabetic individuals”; n = 12) was characterized by older participants with the highest proportion of diabetic participants (100% were diabetic; 73% insulin users), lower BMI, higher DMFT index and OHIP-14 and xerostomia scores, and who reported having consumed fruit and vegetables the day before. Finally, Cluster 3 (labeled “Poor periodontal health”; n = 24) was characterized by participants with the worse periodontal condition (higher CPI), and lower salivary flow, pH, and buffer capacity. Cluster 1 and 2 were the groups that showed higher demand for nutritional and dietetic counseling, because of the poor eating behavior and higher serum glucose levels, respectively. On the other hand, Cluster 2 and 3 showed the higher demand for oral rehabilitation and dental treatment because of the loss of teeth and worse periodontal condition, respectively, besides the need for dietetic counseling. This sample of individuals with morbid obesity showed very unique oral-health and nutritional characteristics and special needs patterns that should be identified to adjust or change unhealthy habits, thus improving the assistance of this condition.

Pre-meal active video game playing increased subjective appetite but not food intake in children and adolescents

OBJECTIVE

Sedentary video game playing (VGP) and caloric preloads in the pre-meal environment have been shown to influence short-term food intake (FI) regulation in children. Other factors that may affect FI control include physical activity and/or heightened emotion. Therefore, we examined the effects of a glucose preload and 30 min of active VGP (aVGP) on subjective appetite, short-term FI, and subjective emotions in 9-14 year-old children.

METHODS

On four test mornings approximately one-week apart, twenty-seven children (sex: 15M, 12F; age: 11.3 ± 0.3 years; BMI percentile: 55.3 ± 6.1%) consumed a standardized breakfast two hours prior to consuming 250 mL of either a 50 g glucose preload or Sucralose® control. Following the preload, participants participated in 30 min of quiet sitting or aVGP. Energy expenditure was measured during aVGP via indirect calorimetry. FI from an ad libitum pizza meal was measured after each test condition. Subjective appetite and emotions were measured at baseline (0 min), during treatment (15min), and immediately before the test meal (30 min).

RESULTS

aVGP did not affect FI, but the glucose preload decreased FI compared with the sucralose control (∆ = 157 kcal, <0.001). Although not statistically significant (p=0.12), caloric compensation was lower following the glucose preload in the aVGP condition. Subjective appetite increased with time, and was higher in the sucralose control + aVGP condition (p=0.05). Change from baseline subjective emotion scores of anger and excitement were higher (p=0.03) and lower (p=0.02) after aVGP, respectively.

CONCLUSIONS

Neither short-term FI nor net energy balance were affected by low-intensity aVGP (energy expenditure of 34 kcal). These findings suggest that a short bout of low-intensity aVGP does not alter energy balance during the study measurement period, and may not support achieving or maintaining healthy weights in children. However, future longitudinal studies are needed to confirm such advice.

How is Satiety Affected When Consuming Food While Working on A Computer?

More people working at offices are choosing to eat meals at their desks, making “desktop dining” an increasingly common phenomenon. Previous studies have reported that environmental distractors, such as television viewing, can influence meal intake and subsequent snack intake. However, the impact of stressful mental tasks on eating behavior has received relatively less attention, focusing only on subsequent meal intake or concurrent snack intake. This study sets out to determine whether eating while working influenced current meal energy intake. This research also examined the relationship between dietary restraint status and energy intake. A crossover experimental design was employed requiring participants (14 males and 29 females) to eat pizza quietly and at rest (control), and while working on a computer (work). Measurements included BMI, energy intake, state anxiety, restrained eating behavior, stress levels (pre- and post-eating), and appetite (before and after both work and control sessions). The findings showed that consuming food while working on a computer significantly increased stress but had no influence on energy intake compared to the control condition. However, post-eating hunger levels were significantly higher in the work condition compared to the control condition. As expected, satiety levels decreased significantly from pre- to post-eating for both work and control conditions. In addition, no significant relationship was observed between restrained eating behavior and energy intake in both work and control conditions. These results suggest that eating while working affected satiety of normal weight participants, as indicated by the significant difference in post-meal satiety levels between work and control conditions.

Effect of dairy and nondairy snacks on postprandial blood glucose regulation in 9-14-year-old children

In adults, dairy consumption improves short-term blood glucose regulation. It is unknown if these short-term benefits extend to children of different weight statuses. The objective of this study was to investigate the effect of a dairy and nondairy snack in both normal-weight (NW) and overweight/obese (OW/OB) children on blood glucose regulation and food intake (FI). In a repeated-measures crossover design, 11 NW and 7 OW/OB children (age: 9-14 years), consumed, in random order, a dairy (Greek yogurt, 198.9 g, 171 kcal, 0 g fat, 17 g protein) or nondairy (mini sandwich-type cookies, 37.5 g, 175 kcal, 7.5 g fat, 1.3 g protein) snack containing 25 g of available carbohydrates. Ad libitum FI was measured 120 min after snack consumption. Blood glucose, insulin, C-peptide, and glucagon-like peptide-1 (GLP-1) were measured at 0 min (before the snack), and at 30, 60, 90, and 120 min after snack consumption. Insulin secretion was calculated from deconvolution of C-peptide. Hepatic insulin extraction was calculated as C-peptide divided by insulin. FI did not differ between snacks (P = 0.55). Mean blood glucose was lower (P < 0.001) and insulin higher (P < 0.0001) in the 120 min after consuming the dairy snack. C-Peptide concentrations (P = 0.75) and insulin secretion (P = 0.37) were not different between snacks. The increase in insulin was explained by reduced hepatic insulin extraction (P < 0.01). Consumption of the dairy snack also increased mean GLP-1 concentrations (P < 0.001). In conclusion, consumption of a dairy snack by NW and OW/OB children results in reduced postprandial blood glucose concentrations and elevated circulating insulin compared with a nondairy snack possibly because of delayed hepatic insulin extraction.

Smartphone use while eating increases caloric ingestion

The use of smartphones during meals may possibly influence the number of ingested calories. We evaluated the influence of smartphones' distraction during eating on caloric intake. Physical (masticatory parameters, sex and body mass index - BMI); environmental (with or without distraction) and psychological (stress levels) variables were evaluated as confounding factors. Sixty-two adults were recruited for experimental snack tests performed on four different days. At baseline, we evaluated masticatory performance, swallowing threshold, masticatory frequency and body mass index (BMI). In the following three sessions, volunteers were presented a snack test in which participants ate under three experimental conditions: no distraction, using their smartphones, or reading a printed text. At the end of each session, total and nutritional compound stratified caloric intake was measured. Three-way mixed model ANOVA was used to test the effect of experimental condition on the total, carbohydrate and lipid caloric intakes. Hierarchical multiple linear regression models were used to estimate the influence of confounding factors on the total caloric intake. We found an effect of the condition (no distraction, smartphone or reading) on the total caloric (p = .007) and lipid intake (p = .002). When eating without distraction, the mean caloric intake was 535 (±164) kcal, in comparison to 591 (±203) kcal using smartphone (p = .05) and 622 (±226) kcal (p = .002) reading a text (no significant difference between distracters). Eating with distracters increased approximately 15% caloric ingestion. An interaction condition*sex effect was observed on lipid intake (p = .020). Energy intake was found to be dependent on sex and age, in which older men ingested more calories. Smartphone use during a meal increased caloric and lipid intake, depending on sex and age in young adults with complete dentition.

Effect of Commercially Available Sugar-Sweetened Beverages on Subjective Appetite and Short-Term Food Intake in Boys

It is unclear whether sugar sweetened beverages bypass regulatory controls of food intake (FI) in boys. The objective of the present study was to determine the effects of isovolumetric preloads (350 mL) of a fruit-flavoured drink (154 kcal), cola (158 kcal), 1% M.F. chocolate milk (224 kcal), and water (0 kcal) on subjective appetite and FI in boys aged 9–14 years. On four separate mornings, boys consumed one of the preloads in a random order; subjective appetite was measured at 15 min intervals, and FI was measured via an ad libitum pizza lunch at 60 min post-beverage consumption. In the 32 boys (age: 11.8 ± 0.3 years), FI was reduced (p < 0.001) after cola (940 ± 46 kcal) and chocolate milk (878 ± 41 kcal) compared with the water control (1048 ± 35 kcal) and after chocolate milk compared to the fruit drink (1005 ± 44 kcal). Cumulative FI after the fruit drink was greater than the water control (1159 ± 44 vs. 1048 ± 35 kcal; p = 0.03). Average appetite was not affected by the treatment, but the cola treatment resulted in greater fullness (p = 0.04) and lower prospective food consumption (p = 0.004) compared with the fruit drink. In conclusion, chocolate milk and cola suppressed next-meal FI at 60 min, while fruit drink increased cumulative FI (beverage + next meal) over 60 min in boys. Results from this study suggest that beverage composition is an important determinant of FI suppression in boys.

Effect of Commercially Available Sugar-Sweetened Beverages on Subjective Appetite and Short-Term Food Intake in Girls

Background: The effect of sugar-sweetened beverages (SSBs) on satiety and short-term food intake (FI) regulation in girls has received little attention. The objective of the present study was to compare the effect of pre-meal consumption of commercially available SSBs on subjective appetite and short-term FI in 9–14-year-old girls. The methods we used include using a randomized crossover design in which 28 girls consumed isovolumetric amounts (350 mL) of a fruit drink (154 kcal), cola (158 kcal), 1% chocolate milk (224 kcal), or water (control; 0 kcal) on four separate mornings. Subjective appetite and thirst were measured at regular intervals via visual analogue scales (VAS) and FI was assessed at 60 min post-beverage consumption. The results show that subjective appetite and thirst decreased after all beverages, but did not differ among beverages. Short-term FI was suppressed following consumption of chocolate milk (15%; p < 0.001) and cola (11%; p = 0.02) compared to the water control. However, cumulative energy intake (beverage (kcal) + test meal (kcal)) was not affected by beverage type. In conclusion, chocolate milk and cola, but not fruit drink, suppressed FI in girls while cumulative FI did not differ among treatments.

Methodological Challenges in Studies Examining the Effects of Breakfast on Cognitive Performance and Appetite in Children and Adolescents

Breakfast is purported to confer a number of benefits on diet quality, health, appetite regulation, and cognitive performance. However, new evidence has challenged the long-held belief that breakfast is the most important meal of the day. This review aims to provide a comprehensive discussion of the key methodological challenges and considerations in studies assessing the effect of breakfast on cognitive performance and appetite control, along with recommendations for future research. This review focuses on the myriad challenges involved in studying children and adolescents specifically. Key methodological challenges and considerations include study design and location, sampling and sample section, choice of objective cognitive tests, choice of objective and subjective appetite measures, merits of providing a fixed breakfast compared with ad libitum, assessment and definition of habitual breakfast consumption, transparency of treatment condition, difficulty of isolating the direct effects of breakfast consumption, untangling acute and chronic effects, and influence of confounding variables. These methodological challenges have hampered a clear substantiation of the potential positive effects of breakfast on cognition and appetite control and contributed to the debate questioning the notion that breakfast is the most important meal of the day.

Pre-meal screen-time activities increase subjective emotions, but not food intake in young girls

PURPOSE

To determine the effect of pre-meal screen-time activities on subjective emotions, subjective appetite, and food intake (FI) in 9-14 year-old girls.

METHODS

In this clinical study, 31 girls completed four 45-min treatment conditions of television viewing (TVV), video game playing (VGP), a challenging computer task (CT), and sitting without screen exposure (control) in a randomized order. Each treatment condition was followed immediately by an ad libitum pizza lunch, and FI was calculated from the weight of the consumed pizza. Subjective appetite was assessed at baseline, 15, 30, and 45 min during the treatment condition, and upon trial completion at 75 min. Subjective emotions were assessed at baseline and at 45 min.

RESULTS

FI was not affected by screen type, but was positively correlated with body composition (fat mass [FM, kg], fat free mass [FFM, kg]) in all treatment conditions. Subjective appetite was not affected by screen type, but increased with time in all treatment conditions (p < 0.0001). Subjective emotions were affected by VGP only. Anger, excitement, frustration, and upset feelings were increased at 45 min following VGP. VGP led to increased frustration compared to control (p = 0.0003), CT (p = 0.007) and TVV (p = 0.0002).

CONCLUSION

Exposure to TVV or CT before eating did not affect subjective emotions, subjective appetite, or FI, and no difference was found between screen activities and the control condition for average appetite or FI. Despite a change in subjective emotions during the VGP condition, there was no increase in subjective appetite or subsequent FI. These findings suggest that physiologic signals of satiation and satiety are not overridden by environmental stimuli of pre-meal screen-time exposure among young girls. (Clinical trial number NCT01750177).

Pre- and within-meal effects of fluid dairy products on appetite, food intake, glycemia, and regulatory hormones in children

The effect of beverages commonly consumed by children in-between or with meals on short-term food intake (FI) and glycemic control has received little attention. Therefore, 2 experiments were conducted in 9- to 14-year-old children following a randomized repeated-measures design. Experiment 1 (n = 32) compared the effects of water (control) and isocaloric (130 kcal) amounts of 2% milk, chocolate milk, yogurt drink, and fruit punch on subjective appetite and FI. Experiment 2 (n = 20) compared the effects of isocaloric (130 kcal) amounts of 2% milk and fruit punch on subjective appetite, FI, and glycemic and appetite hormone responses. One serving of the beverages was given as a pre-meal drink at baseline (0 min) and a second serving 60 min later with an ad libitum pizza meal. Meal FI in experiment 1 was lower by 14% and 10%, respectively, after chocolate milk and yogurt drink (p < 0.001), but not milk, compared with water. Cumulative energy intake (beverages plus meal) was higher after caloric beverages than water. In experiment 2, no differences occurred in pre-meal but post-meal glucose was 83% higher in overweight/obese than normal-weight children (p = 0.02). Milk led to higher pre-meal glucagon-like peptide-1 and post-meal peptide tyrosine tyrosine (PYY) than fruit punch (p < 0.01) but insulin did not differ between treatments. In conclusion, dairy products consumed before and with a meal have more favourable effects on FI, appetite, and satiety hormones than a sugar-sweetened beverage, but all caloric beverages result in more cumulative calories than if water is the beverage.

Pubertal status, pre-meal drink composition, and later meal timing interact in determining children's appetite and food intake

Puberty is a period of development that alters energy intake patterns. However, few studies have examined appetite and food intake (FI) regulation during development of puberty in children and adolescents. Therefore, the objective was to measure the effect of pubertal status on FI and subjective appetite after pre-meal glucose and whey protein drinks in 9- to 14-year-old boys and girls. In a within-subject, randomized, repeated-measures design, children (21 pre-early pubertal, 15 mid-late pubertal) received equally sweetened drinks containing Sucralose (control), glucose, or whey protein (0.75 g/kg body weight) in 250 mL of water 2 h after a standardized breakfast on 6 separate mornings. Ad libitum FI was measured either 30 or 60 min later and appetite was measured over time. In pre-early and mid-late pubertal boys and girls there was no effect of sex on total FI (kcal). Glucose and whey protein drinks reduced calorie intake similarly at 30 min. But at 60 min, whey protein reduced FI (p < 0.001) compared with control and glucose in pre-early pubertal children, but not in mid-late pubertal children. However, sex was a factor (p = 0.041) when FI was expressed per kilogram body weight. Pubertal status did not affect FI/kilogram body weight in boys, but it was 32% lower in mid-late pubertal girls than at pre-early puberty (p = 0.010). Appetite was associated with FI in mid-late pubertal children only. In conclusion, pubertal development affects appetite and FI regulation in children.

The effects of potatoes and other carbohydrate side dishes consumed with meat on food intake, glycemia and satiety response in children

BACKGROUND

The effect of carbohydrate (CHO) foods on blood glucose (BG) is ranked by their glycemic index (GI). Boiled and mashed potatoes (BMPs) are ranked as high GI foods, whereas pasta and rice have moderate GI rankings. The objective of this study was to compare ad libitum consumption of common CHO dishes consumed with meat on meal-time food intake and post-meal satiety, BG, insulin and gut hormones in 11- to 13-year-old normal weight children.

METHODS

Two randomized crossover studies were conducted. At weekly intervals, children (experiment 1: 12 males (M), 8 females (F); experiment 2: 6M, 6 F) received in random order 1 of 5 CHO side dishes of rice, pasta, BMP, fried French fries (FFF) or baked French fries (BFF) eaten freely together with a fixed amount of lean beef (100 g). In experiment-1, food intake over 30 min and subjective appetite were measured for 120 min. In experiment-2, the same outcomes were measured along with BG, plasma insulin and gut hormones.

RESULTS

The results for boys and girls were pooled as sex was not a factor. In both experiments, children consumed 30-40% less calories at meals with BMP (P<0.0001) compared with all other treatments, which were similar. BMP increased satiety, expressed as a change in appetite per kilocalorie, more than all other treatments (P<0.0001). FFF resulted in the lowest (P<0.0001) glucose and insulin at meal end and post-meal and peptide YY (PYY) post-meal. Blood measures were similar among all other treatments.

CONCLUSIONS

The physiological functions of CHO foods consumed ad libitum at meal time on food intake, appetite, BG, insulin and gut hormone responses in children is not predicted by the GI.

Physiology of Food Intake Control in Children

The purpose of this review is to draw attention to the limited information available on food intake (FI) control in children and adolescents 7-17 y of age, which is essential for developing food policies and guidelines in this population. Although environmental factors have been the overwhelming focus of research on the causative factors of obesity, research focusing on the physiologic control of appetite in children and adolescents is a neglected area of research. To present this message, a review of FI regulation and the role of food and food components in signaling processes are followed by an examination of the role of hormones during puberty in intake regulation. To examine the interaction of environment and physiology on FI regulation, the effects of exercise, television programs, and food advertisements are discussed. In conclusion, although limited, this literature review supports a need for children and adolescents to be a greater focus of research that would lead to sound nutrition policies and actions to reduce chronic disease. A focus on the environment must be balanced with an understanding of physiologic and behavioral changes associated with this age group.

Does low-energy sweetener consumption affect energy intake and body weight? A systematic review, including meta-analyses, of the evidence from human and animal studies

By reducing energy density, low-energy sweeteners (LES) might be expected to reduce energy intake (EI) and body weight (BW). To assess the totality of the evidence testing the null hypothesis that LES exposure (versus sugars or unsweetened alternatives) has no effect on EI or BW, we conducted a systematic review of relevant studies in animals and humans consuming LES with ad libitum access to food energy. In 62 of 90 animal studies exposure to LES did not affect or decreased BW. Of 28 reporting increased BW, 19 compared LES with glucose exposure using a specific ‘learning' paradigm. Twelve prospective cohort studies in humans reported inconsistent associations between LES use and body mass index (−0.002 kg m⁻² per year, 95% confidence interval (CI) −0.009 to 0.005). Meta-analysis of short-term randomized controlled trials (129 comparisons) showed reduced total EI for LES versus sugar-sweetened food or beverage consumption before an ad libitum meal (−94 kcal, 95% CI −122 to −66), with no difference versus water (−2 kcal, 95% CI −30 to 26). This was consistent with EI results from sustained intervention randomized controlled trials (10 comparisons). Meta-analysis of sustained intervention randomized controlled trials (4 weeks to 40 months) showed that consumption of LES versus sugar led to relatively reduced BW (nine comparisons; −1.35 kg, 95% CI –2.28 to −0.42), and a similar relative reduction in BW versus water (three comparisons; −1.24 kg, 95% CI –2.22 to −0.26). Most animal studies did not mimic LES consumption by humans, and reverse causation may influence the results of prospective cohort studies. The preponderance of evidence from all human randomized controlled trials indicates that LES do not increase EI or BW, whether compared with caloric or non-caloric (for example, water) control conditions. Overall, the balance of evidence indicates that use of LES in place of sugar, in children and adults, leads to reduced EI and BW, and possibly also when compared with water.

Modern screen-use behaviors: the effects of single- and multi-screen use on energy intake

PURPOSE

The effects of using multiple screens at once on energy intake (EI) are unknown. This study compared EI of participants with access to multiple screens (television + iPad + smartphone) versus a single screen (television).

METHODS

A laboratory-based, randomized, two-arm parallel (multi-screen vs. single-screen) trial was conducted in 78 adolescents (ages, 13-18 years). Food and drink were available during a 1-hour exposure period. Total EI was the primary outcome. Linear regression analyses were conducted to test the treatment difference, adjusting for age, sex, body mass index, and appetite at baseline.

RESULTS

Total EI did not differ significantly between the two groups (multi-screen, 758 kcal [standard error = 75] vs. single-screen, 681 kcal [standard error = 75]; difference, +77 kcal; 95% confidence interval, -166 to +320).

CONCLUSIONS

EI did not differ between adolescents with access to multiple screens and those with access to a single screen; however, limitations in the study design may have decreased the power of the study.

Weighing the Evidence of Common Beliefs in Obesity Research

Obesity is a topic on which many views are strongly held in the absence of scientific evidence to support those views, and some views are strongly held despite evidence to contradict those views. We refer to the former as "presumptions" and the latter as "myths." Here, we present nine myths and 10 presumptions surrounding the effects of rapid weight loss; setting realistic goals in weight loss therapy; stage of change or readiness to lose weight; physical education classes; breastfeeding; daily self-weighing; genetic contribution to obesity; the "Freshman 15"; food deserts; regularly eating (versus skipping) breakfast; eating close to bedtime; eating more fruits and vegetables; weight cycling (i.e., yo-yo dieting); snacking; built environment; reducing screen time in childhood obesity; portion size; participation in family mealtime; and drinking water as a means of weight loss. For each of these, we describe the belief and present evidence that the belief is widely held or stated, reasons to support the conjecture that the belief might be true, evidence to directly support or refute the belief, and findings from randomized controlled trials, if available. We conclude with a discussion of the implications of these determinations, conjecture on why so many myths and presumptions exist, and suggestions for limiting the spread of these and other unsubstantiated beliefs about the obesity domain.

Mealtime exposure to food advertisements while watching television increases food intake in overweight and obese girls but has a paradoxical effect in boys

Food advertisements (ads) in TV programs influence food choice and have been associated with higher energy intake from snacks in children; however, their effects at mealtime have not been reported. Therefore, we measured energy intake at a pizza meal consumed by normal weight (NW) and overweight/obese (OW/OB) children (aged 9-14 years) while they watched a TV program with or without food ads and following pre-meal consumption of a sweetened beverage with or without calories. NW and OW/OB boys (experiment 1, n = 27) and girls (experiment 2, n = 23) were randomly assigned to consume equally sweetened drinks containing glucose (1.0 g/kg body weight) or sucralose (control). Food intake was measured 30 min later while children watched a program containing food or nonfood ads. Appetite was measured before (0-30 min) and after (60 min) the meal. Both boys and girls reduced energy intake at the meal in compensation for energy in the glucose beverage (p < 0.05). Food ads resulted in further compensation (51%) in boys but not in girls. Food ads increased energy intake at the meal (9%; p = 0.03) in OW/OB girls only. In conclusion, the effects of TV programs with food ads on mealtime energy intake and response to pre-meal energy consumption in children differ by sex and body mass index.

Obesity, sex and pubertal status affect appetite hormone responses to a mixed glucose and whey protein drink in adolescents

BACKGROUND AND OBJECTIVES

Little information is available on how food intake regulatory hormones may be altered during pubertal development and across the weight spectrum in adolescents. Therefore, the effect of obesity, sex and pubertal status on subjective appetite and appetite hormones in response to a mixed glucose and whey protein drink was determined in 8-18 year old adolescents.

PATIENTS AND METHODS

A cross-sectional cohort study was conducted at the Hospital for Sick Children, Toronto. After a 12 h fast, normal weight (n = 5 female, 4 male) and obese (n = 5 female, 4 male) adolescents (Experiment 1), and pre-early pubertal (n = 10) and mid-late pubertal (n = 10) obese male adolescents (Experiment 2) consumed a 250 ml glucose (30 g) and whey protein (30 g) beverage. Insulin, PYY, ghrelin and subjective appetite were measured over 120 min.

RESULTS

Obese adolescents (Experiment 1) have higher insulin, PYY and lower ghrelin (P < 0·006) than normal weight controls, with a more pronounced effect in males (P < 0·037). Puberty (Experiment 2) did not affect insulin (P = 0·305), but the change in PYY in response to the drink was greater (P = 0·032) and ghrelin was lower (P = 0·026) in mid-late pubertal than pre-early pubertal obese males. Average appetite 60 min post-drink was higher in obese and mid-late pubertal adolescents, but not related to hormone changes.

CONCLUSIONS

Obesity, sex and pubertal status affect macronutrient-stimulated appetite hormone secretion and these factors may alter food intake in obese children during pubertal development.

An after-school snack of raisins lowers cumulative food intake in young children

Snacks are an important part of children's dietary intake, but the role of dried fruit on energy intake in children is unknown. Therefore, the effect of ad libitum consumption of an after-school snack of raisins, grapes, potato chips, and chocolate chip cookies on appetite and energy intake in twenty-six 8- to 11-y-old normal-weight (15th to 85th percentile) children was examined. On 4 separate weekdays, 1 wk apart, children (11 M, 15 F) were given a standardized breakfast, morning snack (apple), and a standardized lunch. After school, children randomly received 1 of 4 ad libitum snacks and were instructed to eat until "comfortably full." Appetite was measured before and 15, 30, and 45 min after snack consumption. Children consumed the least calories from raisins and grapes and the most from cookies (P < 0.001). However, weight of raisins consumed was similar to potato chips (about 75 g) and lower compared to grapes and cookies (P < 0.009). Raisins and grapes led to lower cumulative food intake (breakfast + morning snack + lunch + after-school snack) (P < 0.001), while the cookies increased cumulative food intake (P < 0.001) compared to the other snacks. Grapes lowered appetite compared to all other snacks (P < 0.001) when expressed as a change in appetite per kilocalorie of the snack. Ad libitum consumption of raisins has potential as an after-school snack to achieve low snack intake prior to dinner, similar to grapes, compared to potato chips, and cookies in children 8 to 11 y old.

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.

Puberty as a critical risk period for eating disorders: a review of human and animal studies

This article is part of a Special Issue "Puberty and Adolescence". Puberty is one of the most frequently discussed risk periods for the development of eating disorders. Prevailing theories propose environmentally mediated sources of risk arising from the psychosocial effects (e.g., increased body dissatisfaction, decreased self-esteem) of pubertal development in girls. However, recent research highlights the potential role of ovarian hormones in phenotypic and genetic risk for eating disorders during puberty. The goal of this paper is to review data from human and animal studies in support of puberty as a critical risk period for eating disorders and evaluate the evidence for hormonal contributions. Data are consistent in suggesting that both pubertal status and pubertal timing significantly impact risk for most eating disorders in girls, such that advanced pubertal development and early pubertal timing are associated with increased rates of eating disorders and their symptoms in both cross-sectional and longitudinal research. Findings in boys have been much less consistent and suggest a smaller role for puberty in risk for eating disorders in boys. Twin and animal studies indicate that at least part of the female-specific risk is due to genetic factors associated with estrogen activation at puberty. In conclusion, data thus far support a role for puberty in risk for eating disorders and highlight the need for additional human and animal studies of hormonal and genetic risk for eating disorders during puberty.

A premeal snack of raisins decreases mealtime food intake more than grapes in young children

The effect of a premeal snack of grapes, raisins, or a mix of almonds and raisins, compared with a water control, on food intake (FI) was examined in 8- to 11-year-old normal-weight (15th to 85th percentile) children. Children randomly received 1 of 4 ad libitum (Experiment 1: 13 boys, 13 girls) or fixed-calorie (150 kcal; Experiment 2: 13 boys, 13 girls) treatments, followed by an ad libitum pizza meal 30 min later. Appetite was measured throughout the study, and FI was measured at 30 min. The ad libitum consumption (Experiment 1) of raisins reduced pizza intake (p < 0.037), compared with water (26%), grapes (22%), and the mixed snack (15%). Cumulative energy intake (in kcal: snack + pizza) was lower after water and raisins than after either grapes or the mixed snack (p < 0.031). As a fixed-calorie (150 kcal) snack (Experiment 2), raisins reduced pizza intake, compared with water (∼11%, p = 0.005), and resulted in a cumulative intake similar to water; however, both grapes and the mixed snack resulted in higher cumulative intakes (p < 0.015). Appetite was lower after all caloric ad libitum snacks (p < 0.003) and after fixed amounts of grapes and the mixed snack (p < 0.037), compared with water. In conclusion, consumption of a premeal snack of raisins, but not grapes or a mix of raisins and almonds, reduces meal-time energy intake and does not lead to increased cumulative energy intake in children.

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.

Overweight and obese boys reduce food intake in response to a glucose drink but fail to increase intake in response to exercise of short duration

The effect of short duration exercise (EXR) on food intake (FI) and energy balance (EB) is not well understood in either normal weight (NW) or overweight (OW) and obese (OB) 9-14 years old children. Our purpose was to describe the effects of activity and a glucose drink on short term FI, appetite, and EB in NW, OW, and OB boys. Each boy received in random order either a noncaloric Sucralose sweetened control or glucose (1.0 g·kg(-1) body weight) drink 5 min after either exercise (EXR) or sedentary (SED) activity. Boys exercised for 15 min at their ventilation threshold (V(T)) in experiment 1 or at 25% above their V(T) in experiment 2. FI was measured at an ad libitum pizza meal 30 min after drink consumption. FI was lower after the glucose drink (p < 0.001) but not affected by activity, even though EXR increased appetite (p < 0.001). OW/OB boys ate more total food than NW boys (p = 0.020). EB over the duration of the experiments was reduced by EXR in OW/OB boys (p = 0.013) but not in NW boys in either experiment (p > 0.05). We conclude that intake regulation in OW/OB boys in response to a glucose drink is similar to NW boys, but it may be less responsive to activity.