The Frequency and Context of Snacking among Children: An Objective Analysis Using Wearable Cameras

Investigating eating architecture and the impact of the precision of recorded eating time: a cross-sectional study

BACKGROUND

The precision of recorded eating times directly affects the estimation of eating architecture i.e. size, timing, and frequency of eating. The impact of imprecise timing on estimates and associations of eating architecture with health remains unclear.

OBJECTIVE

We compared eating architecture variables derived from precise versus broad timing methods and examined associations with anthropometric and diet-related outcomes.

METHODS

Cross-sectional data came from 3-day diet diaries of 7-year-old children in the Avon Longitudinal Study of Parents and Children. We derived average size, timing, and frequency of eating, utilizing exact times (precise, n=4855) and mid-point meal slot times (broad, n=7285). Intraclass correlation coefficients (ICC) estimated agreement between methods. Bland-Altman analysis determined mean difference and limits of agreement (LOA). Correlations (95% confidence intervals) estimated associations between eating architecture variables and anthropometric or diet-related traits.

RESULTS

Agreement varied from moderate to excellent for size (ICC 0.75), last or first time (ICC 0.80 or 0.58), and frequency (ICC 0.43) of Eating Occasions (EOs). Broad times underestimated eating frequency (2.2 times/day; LOA -1, 5) and overestimated size (83g; LOA -179, 13), last time (50min; LOA -142, 42), inter-meal intervals (68min; LOA -126, -11) and eating window (49min; LOA -161, 63). Directions of eating architecture intercorrelations were consistent regardless of time precision but varied in magnitude, e.g., larger EO size correlated with lower eating frequency but was stronger with precise time (rprecise=-0.54 (95% CI -0.56, -0.52); rbroad=-0.24 (-0.27, -0.22)). Correlations with anthropometric and diet outcomes were also directionally consistent.

CONCLUSIONS

Precise timing improves the estimation of eating architecture. Differences in estimation will affect descriptions of children's eating habits and possibly dietary guidance. However, consistent directional associations across timing methods, suggest that broad times could provide a pragmatic method for investigating eating architecture associations in large samples.

Facilitators and barriers to healthful eating among adolescents in high-income countries: A mixed-methods systematic review

Adolescent obesity continues to be a public health challenge with poor quality diets contributing to its etiology. As part of the process to plan health promotion and policy interventions, understanding adolescents perceived facilitators and barriers to healthful eating is important. An integrative convergent mixed-methods systematic review was used to synthesize qualitative and quantitative evidence from studies among adolescents aged 10-19 years in high-income countries. Medline, Embase, PsycInfo, and Scopus were searched for peer-reviewed articles published between 2010 and 2023 and exploring adolescents' perspectives on healthful eating and contemporary contextual factors. Transformed quantitative data were integrated with qualitative data. Text was coded into subthemes and themes using an inductive approach. Key facilitators included health and physical appearance; motivation; taste; nutrition knowledge, awareness, and skills; nutrition education access; availability and accessibility of healthful foods; family; and social influences and digital media. Key barriers included taste and cravings for unhealthful foods; mood; lack of motivation, awareness, knowledge, and skills; high availability and low cost of unhealthful foods; peers and social influences; ineffective school policies; high density of fast-food outlets; unhealthful food advertising; digital influences; and time constraints. Social, behavioral, digital, and food environmental factors should be considered from an adolescent perspective in the design of education, health promotion, and policy interventions.

Experiences of discrimination and snacking behavior in Black and Latinx children

Little is known about how discrimination contributes to health behaviors in childhood. We examined the association between children's exposure to discrimination and their snacking behavior in a sample of youth of color (N = 164, Mage = 11.5 years, 49% female, 60% Black, 40% Hispanic/Latinx). We also explored whether children's body mass index (BMI) or sleepiness moderated the association between discrimination and calorie consumption. The significant link between discrimination and calorie consumption was moderated by children's BMI, such that discrimination was associated with calorie consumption for children with BMI percentiles above 79%. Children's sleepiness did not serve as an additional moderator. Efforts to promote health should consider children's broader socio-contextual experiences, including discrimination, as factors that may shape eating patterns.

Comparison of snack characteristics by diet quality findings from a nationally representative study of Australian adolescents

Snacking is a common dietary behaviour among adolescents contributing to more than one quarter of their total energy intake; however, the relationship between snacks and diet quality remains unclear. Hence, this study aimed to examine the characteristics of snacks among adolescents with different levels of diet quality. Dietary data collected from a nationally representative sample of Australian adolescents (12-18 years old, n = 935) using one 24-hour dietary recall in the National Nutrition and Physical Activity Survey were analysed. Snacks were defined based on participant-identified eating occasions, and diet quality was assessed using the Dietary Guideline Index for Children and Adolescents (DGI-CA). Marginal means and proportion of snack characteristics including snack frequency, snack energy density (ED), and commonly consumed foods at snack from the five food groups and discretionary foods at snack across DGI-CA tertiles (highest tertile indicating high guideline adherence) were estimated for both boys and girls using linear regression and logistic regression. Differences in means were tested using the F-test. The results showed no significant differences in the mean frequency of snacks across tertiles of DGI-CA scores. The mean ED of snacks decreased as DGI-CA scores increased in both boys (lowest tertile = 8.4, 95% CI [7.1, 10.0] kJ/g, highest tertile = 6.3 [5.4, 7.4] kJ/g) and girls (lowest tertile = 9.0 [7.8, 10.3] kJ/g, highest tertile = 5.9 [5.1, 6.9] kJ/g). As diet quality improved, the proportion of adolescents consuming discretionary (i.e., unhealthy) foods and foods from the five food group foods as snacks decreased and increased, respectively. In conclusion, adolescents with higher diet quality consumed snacks with a lower ED while lower proportion of them consume discretionary foods, and higher proportion of them consume from the five food groups. Encouraging the consumption of foods from the five food groups with lower ED as snacks presents an opportunity to enhance adolescent diet quality.

Diabetes Cam: An Objective Methodology to Study Diabetes Self-Management

INTRODUCTION

The prevalence of Type 2 Diabetes Mellitus (T2DM) is rapidly increasing throughout the world. T2DM is primarily a self-managed disease yet clinical studies indicate that a large proportion of adults with T2DM struggle to self-manage their diabetes. This puts them at high risk of developing diabetes-related complications. This study presents Diabetes Cam, a new methodology to objectively study T2DM self-management and identify its barriers and facilitators.

METHODS

Thirty adults with diabetes of i-taukei descent from the 4 medical divisions throughout Fiji wore a camera for 4 days that automatically recorded images every 7 seconds. They also participated in in-depth photo-elicitation interviews to explore their experiences and perceptions of T2DM self-management. Data was collected between October 2021 and May 2022, and the analysis was done in August 2023.

RESULTS

Approximately 11,500 images per participant were generated providing rich data. The method is ethical, legal, and acceptable for adults with T2DM, their families, and the wider community. The images can be readily coded for food availability and consumption, physical activity, transportation, medication use, and foot care. Photo-elicitation enabled further information on what was occurring within the images and about participants' perspectives on diabetes self-management.

CONCLUSIONS

The Diabetes Cam methodology enabled automated, objective observation of participants' T2DM self-management and their perspectives on self-management. It provides unique insights into diabetes self-management and ways to improve diabetes self-management. It provides valuable data to develop strategies to enhance diabetes self-management for people living with diabetes, their families, the wider community, health professionals, and policymakers.

The effect of discretionary snack consumption on overall energy intake, weight status, and diet quality: A systematic review

The consumption frequency and portion size of discretionary snacks are thought to contribute to a greater food intake and risk of overweight or obesity in the developed world but evidence from epidemiological studies is inconclusive. To investigate this, we systematically evaluated evidence on the effects of discretionary snack consumption on weight status, energy intake, and diet quality. Articles involving discretionary snacks reported against the outcome measures of any primary, peer-reviewed study using human participants from free-living conditions for all age groups were included. A total of 14,780 titles were identified and 40 eligible publications were identified. Three key outcomes were reported: weight status (n = 35), energy intake (n = 11), and diet quality (n = 3). Increased discretionary snack consumption may contribute modestly to energy intake, however, there is a lack of consistent associations with increased weight/BMI. Although cross-sectional analyses offered conflicting findings, longitudinal studies in adults showed a consistent positive relationship between discretionary snack intake and increasing weight or body mass index. Given that experimental findings suggest reducing the size of discretionary snacks could lead to decreased consumption and subsequent energy intake, food policy makers and manufacturers may find it valuable to consider altering the portion and/or packaging size of discretionary snacks.

The use of internet-based smartphone apps consistently improved consumers' healthy eating behaviors: a systematic review of randomized controlled trials

Introduction

Digital tools, such as mobile apps and the Internet, are being increasingly used to promote healthy eating habits. However, there has been inconsistent reporting on the effectiveness of smartphones and web-based apps in influencing dietary behaviors. Moreover, previous reviews have been limited in scope, either by focusing on a specific population group or by being outdated. Therefore, the purpose of this review is to investigate the impacts of smartphone- and web-based dietary interventions on promoting healthy eating behaviors worldwide.

Methods

A systematic literature search of randomized controlled trials was conducted using databases such as Google Scholar, PubMed, Global Health, Informit, Web of Science, and CINAHL (EBSCO). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed to prepare the entire document. EndNote (version 20) was used for reference management. The risk of bias in the articles was assessed using the "Revised Cochrane Risk of Bias tool for randomized trials (RoB 2.0)" by the Cochrane Collaboration. Narrative synthesis, using text and tables, was used to present the results. The study was registered in PROSPERO under protocol number CRD42023464315.

Results

This review analyzed a total of 39 articles, which consisted of 25 smartphone-based apps and 14 web-based apps. The studies involved a total of 14,966 participants. Out of the 25 studies, 13 (52%) showed that offline-capable smartphone apps are successful in promoting healthier eating habits. The impact of smartphone apps on healthy adults has been inconsistently reported. However, studies have shown their effectiveness in chronically ill patients. Likewise, internet-based mobile apps, such as social media or nutrition-specific apps, have been found to effectively promote healthy eating behaviors. These findings were consistent across 14 studies, which included healthy adults, overweight or obese adults, chronically ill patients, and pregnant mothers.

Conclusion

Overall, the findings suggest that smartphone apps contribute to improving healthy eating behaviors. Both nutrition-specific and social media-based mobile apps consistently prove effective in promoting long-term healthy eating habits. Therefore, policymakers in the food system should consider harnessing the potential of internet-based mobile apps and social media platforms to foster sustainable healthy eating behaviors.

Development of a Protocol for Objectively Measuring Digital Device Use in Youth

INTRODUCTION

Screen time is predominantly measured using questionnaires assessing a limited range of activities. This project aimed to develop a coding protocol that reliably identified screen time, including device type and specific screen behaviors, from video-camera footage.

METHODS

Screen use was captured from wearable and stationary PatrolEyes video cameras in 43 participants (aged 10-14 years) within the home environment (May-December 2021, coding in 2022, statistical analysis in 2023). After extensive piloting, the inter-rater reliability of the final protocol was determined in 4 coders using 600 minutes of footage from 18 participants who spent unstructured time on digital devices. Coders independently annotated all footage to determine 8 device types (e.g., phone, TV) and 9 screen activities (e.g., social media, video gaming) using Observer XT (behavioral coding software). Reliability was calculated using weighted Cohen's κ for duration per sequence (meets criteria for total time in each category) and frequency per sequence (meets criteria for total time in each category and order of use) for every coder pair on a per-participant and footage type basis.

RESULTS

Overall reliability of the full protocol was excellent (≥0.8) for both duration per sequence (κ=0.89-0.93) and the more conservative frequency per sequence (κ=0.83-0.86) analyses. This protocol reliably differentiates between different device types (κ=0.92-0.94) and screen behaviors (κ=0.81-0.87). Coder agreement ranged from 91.7% to 98.8% across 28.6-107.3 different instances of screen use.

CONCLUSIONS

This protocol reliably codes screen activities in adolescents, offering promise for improving the understanding of the impact of different screen activities on health.

Changes in Food Consumption and Eating Behaviours of Children and Their Families Living in Italy during the COVID-19 Pandemic: The EPaS-ISS Study

The aim of the EPaS-ISS study was to describe the changes in food consumption and eating behaviours of children (mainly aged 8-9 years) and their families between the pre-COVID-19 period (before February/March 2020) and the COVID-19 period (from February/March 2020 to April 2022). A web questionnaire completed by parents was used to collect data. The sociodemographic characteristics of the children and their parents were also explored through the web questionnaire. Seventeen regions out of nineteen and the two autonomous provinces (PA) of Italy participated in the study. The survey was completed for 4863 children (47.9% females). The study showed that only small changes in children's food consumption happened between the pre-COVID-19 period and the COVID-19 period; in particular, about 25% of parents reported an increase in savoury snacks and sweet food. A decrease in fruit and vegetable (about 8%) and fish (14%) consumption was also found. However, the changes seem to have mainly affected children from most disadvantaged families. The results also indicate positive changes during the COVID-19 pandemic in some families' eating behaviours, such as eating more home-cooked meals (42%) and family meals (39%), as well as cooking more with children (42%).

The utilisation of legal instruments by United Nations actors to restrict the exposure of children to unhealthy food and beverage marketing: a qualitative content analysis of UN instruments

INTRODUCTION

United Nations (UN) agencies are influential global health actors that can introduce legal instruments to call on Member States to act on pressing issues. This paper examines the deployment and strength of global health law instruments used by UN actors to call on Member States to restrict the exposure of children to unhealthy food and beverage marketing.

METHODS

Global health law instruments were identified from a review of four UN agencies that have a mandate over children's exposure to marketing of unhealthy food and beverage products namely: the World Health Organization (WHO); the Food and Agriculture Organization (FAO); the United Nations General Assembly (UNGA) and the UN Office of the High Commissioner for Human Rights (OHCHR). Data on marketing restrictions were extracted and coded and descriptive qualitative content analysis was used to assess the strength of the instruments.

RESULTS

A wide range of instruments have been used by the four agencies: seven by the WHO; two by the FAO; three by the UNGA; and eight by the UN human rights infrastructure. The UN human rights instruments used strong, consistent language and called for government regulations to be enacted in a directive manner. In contrast, the language calling for action by the WHO, FAO and UNGA was weaker, inconsistent, did not get stronger over time and varied according to the type of instrument used.

CONCLUSION

This study suggests that a child rights-based approach to restricting unhealthy food and beverage marketing to children would be supported by strong human rights legal instruments and would allow for more directive recommendations to Member States than is currently provided by WHO, FAO and UNGA. Strengthening the directives in the instruments to clarify Member States' obligations using both WHO and child rights mandates would increase the utility of global health law and UN actors' influence.

Capturing children food exposure using wearable cameras and deep learning

Children's dietary habits are influenced by complex factors within their home, school and neighborhood environments. Identifying such influencers and assessing their effects is traditionally based on self-reported data which can be prone to recall bias. We developed a culturally acceptable machine-learning-based data-collection system to objectively capture school-children's exposure to food (including food items, food advertisements, and food outlets) in two urban Arab centers: Greater Beirut, in Lebanon, and Greater Tunis, in Tunisia. Our machine-learning-based system consists of 1) a wearable camera that captures continuous footage of children's environment during a typical school day, 2) a machine learning model that automatically identifies images related to food from the collected data and discards any other footage, 3) a second machine learning model that classifies food-related images into images that contain actual food items, images that contain food advertisements, and images that contain food outlets, and 4) a third machine learning model that classifies images that contain food items into two classes, corresponding to whether the food items are being consumed by the child wearing the camera or whether they are consumed by others. This manuscript reports on a user-centered design study to assess the acceptability of using wearable cameras to capture food exposure among school children in Greater Beirut and Greater Tunis. We then describe how we trained our first machine learning model to detect food exposure images using data collected from the Web and utilizing the latest trends in deep learning for computer vision. Next, we describe how we trained our other machine learning models to classify food-related images into their respective categories using a combination of public data and data acquired via crowdsourcing. Finally, we describe how the different components of our system were packed together and deployed in a real-world case study and we report on its performance.

Wearable Cameras Reveal Large Intra-Individual Variability in Timing of Eating among Young Adults

Studies have shown that young adults follow less structured eating patterns compared with older cohorts. This may have implications for dietary assessment methods which rely on memory and structured meal patterns. Our aim was to describe the intra-individual variation of eating times in young adults aged 18−30 years. Participants (n = 41) wore an Autographer camera that captured first-person perspective images every 30 s for three consecutive days. All images were timestamped and those showing food consumption were used to extract data such as the timing of the first and last eating occasions (EOs), number of EOs per day, and length of eating window. Intra-individual variability was calculated from these data using composite phase deviation (CPD) and coefficient of variation (CV). The number of individuals with high or very high variability was 28 and 18 for timing of first and last EOs, respectively (CPD > 1.70), and 27 and 17 for number of EOs and eating window, respectively (CV > 20%). In this sample of young adults, the lack of regularity in eating patterns should be considered when selecting a dietary assessment method.

The energy density of meals and snacks consumed by young Australian adults (18-30 years old) are influenced by preparation location but not screen use nor social interactions: findings from the MYMeals wearable camera study

The present study examined the association of contextual factors (social and food preparation location) with the energy density of meals and snacks consumed in a sample of young Australian adults (18-30 years old) identified using wearable camera technology. Over three consecutive days, a subsample of young adults wore a wearable camera that captured images in 30 s intervals. Eating episodes from 133 participants were annotated for preparation location and social context (covering social interaction and screen use). Over the same period, participants completed daily 24 h recalls. The nutritional composition of meals and snacks was calculated by matching the items identified in the camera to the 24 h recall using time and date stamps. Self-reported data (weight and height) was used to calculate body mass index and (residential postcode) to assign socio-economic status. The association of context and demographic factors with energy density was determined using a mixed linear regression model employing the bootstrap method with bias-corrected and accelerated. In total, 1817 eating episodes were included in the analysis (n 8 preparation unclear and n 15 food components could not be identified excluded). Food prepared within the home was 1⋅1 kJ/g less energy-dense than other preparation locations. Lunches (CI -1⋅7 to -0⋅3) and dinners (CI -1⋅6 to -0⋅5) were both 1⋅0 kJ/g lower in energy density than breakfasts. Snacks were 3⋅5 kJ/g (CI 2⋅8-4⋅1) more energy-dense than breakfasts. Food prepared outside the home and food consumption during snacking appear to be adversely contributing to energy-dense food intake.

Adolescent Knowledge, Attitudes and Practices of Healthy Eating: Findings of Qualitative Interviews among Hong Kong Families

To tackle unhealthy eating among adolescents, it is crucial to understand the dietary knowledge, attitudes, and practices (KAP) on which adolescent eating habits are based. This qualitative study identifies the gaps in KAP by exploring what Chinese adolescents know, perceive, and practice regarding healthy eating to better inform targeted interventions for this important health problem. Parent–adolescent dyads were purposively sampled based on, for example, the dietary intake, age, and gender of the adolescent and household income, and each completed a 30 to 60 min interview. Twelve themes were synthesized: knowledge: (1) dietary recommendations, (2) health outcomes of healthy eating, (3) nutrition content in food, and (4) access to healthy meals; attitudes: (5) outcome expectation for healthy eating, (6) food preferences, and (7) self-efficacy regarding adopting healthy eating; and practices: (8) going grocery shopping for healthy food, (9) eating home-prepared meals. (10) eating out in restaurants or consuming takeaway food, (11) fruit and vegetable consumption, and (12) snacking, perceived unhealthy eating to be low risk, made unhealthy choices regarding snacking and eating out, and had insufficient fruit and vegetable intake. Programs should emphasize the positive short-term health outcomes of healthy eating and empower adolescents to acquire food preparation skills to sustain healthy eating habits.

Children's Community Nutrition Environment, Food and Drink Purchases and Consumption on Journeys between Home and School: A Wearable Camera Study

Children's community nutrition environments are an important contributor to childhood obesity rates worldwide. This study aimed to measure the type of food outlets on children's journeys to or from school, children's food purchasing and consumption, and to determine differences by ethnicity and socioeconomic status. In this New Zealand study, we analysed photographic images of the journey to or from school from a sample of 147 children aged 11-13 years who wore an Autographer camera which recorded images every 7 s. A total of 444 journeys to or from school were included in the analysis. Camera images captured food outlets in 48% of journeys that had a component of active travel and 20% of journeys by vehicle. Children who used active travel modes had greater odds of exposure to unhealthy food outlets than children who used motorised modes; odds ratio 4.2 (95% CI 1.2-14.4). There were 82 instances of food purchases recorded, 84.1% of which were for discretionary foods. Of the 73 food and drink consumption occasions, 94.5% were for discretionary food or drink. Children on their journeys to or from school are frequently exposed to unhealthy food outlets. Policy interventions are recommended to limit the availability of unhealthy food outlets on school routes.

The association of social and food preparation location context with the quality of meals and snacks consumed by young adults: findings from the MYMeals wearable camera study

PURPOSE

This study examined the association of social contexts and food preparation location with the quality of meals and snacks (predominately from the five food groups (FFG) versus discretionary foods) in a sample of young Australian adults (18-30 years old) using wearable camera technology.

METHODS

A sub-sample from the cross-sectional MYMeals study wore a wearable camera that captured images every 30 s for three consecutive days. Eating episodes from 133 participants (55% female) were classified across 4 domains: food quality (observed proportion of FFG and discretionary items), preparation location, social interaction, and screen use. Socio-economic status (SES) was assigned using residential postcode and gender self-reported. Associations of contexts and demographic factors with food quality stratified by meal type were determined using mixed binary logistic regression models.

RESULTS

Of the 1840 eating episodes identified, 1775 were included in analysis (n = 8 preparation location and n = 57 food components that could not be identified were excluded). Food prepared at home was more likely to be from the FFG at lunch (OR = 4.8 95% CI 2.7-8.6), dinner (OR = 14.8 95% CI 7.6-28.6), and snacks (OR = 3.2 95% CI 2.2-4.8). Participants from higher SES areas were more likely to consume breakfasts (OR = 3.2 95% CI 1.4-7.4) and lunches (OR = 1.9 95% CI 1.0-3.7) predominately from the FFG. Females were more likely to consume lunches (OR = 2.0 95% CI 1.1-3.8) that was largely from the FFG. Social interaction and screen use were not associated with meal or snack quality.

CONCLUSION

Wearable cameras have verified the importance of addressing meals and snacks prepared outside of home as an important contributor of discretionary food.

Home-Based Monitoring of Eating in Adolescents: A Pilot Study

Objectives: To investigate eating episodes in a group of adolescents in their home-setting using wearable electromyography (EMG) and camera, and to evaluate the agreement between the two devices. Approach: Fifteen adolescents (15.5 ± 1.3 years) had a smartphone-assisted wearable-EMG device attached to the jaw to assess chewing features over one evening. EMG outcomes included chewing pace, time, episode count, and mean power. An automated wearable-camera worn on the chest facing outwards recorded four images/minute. The agreement between the camera and the EMG device in detecting eating episodes was evaluated by calculating specificity, sensitivity, and accuracy. Main results: The features of eating episodes identified by EMG throughout the entire recording time were (mean (SD)); chewing pace 1.64 (0.20) Hz, time 10.5 (10.4) minutes, episodes count 56.8 (39.0), and power 32.1% (4.3). The EMG device identified 5.1 (1.8) eating episodes lasting 27:51 (16:14) minutes whereas the cameras indicated 2.4 (2.1) episodes totaling 14:49 (11:18) minutes, showing that the EMG-identified chewing episodes were not all detected by the camera. However, overall accuracy of eating episodes identified ranged from 0.8 to 0.92. Significance: The combination of wearable EMG and camera is a promising tool to investigate eating behaviors in research and clinical-settings.