The impact of the first COVID-19 lockdown on weight management practices in UK adults: A self-regulation perspective

This study aimed to identify the impact of the first UK COVID-19 lockdown on individuals' weight management attempts (WMA). A self-regulation theoretical framework was used to identify predictors of continuing with a WMA, and weight change during the lockdown. An online retrospective cross-sectional study was conducted after the first UK COVID-19 lockdown. The sample consisted of 166 UK adults (M:31.08, SD:12.15) that were trying to manage their weight before the lockdown started. The survey assessed changes in WMA and practices, and measured perceived stress, flexible/rigid restraint, uncontrolled eating, craving control, and self-compassion. Results showed that 56% of participants reported disruption to their WMA during the lockdown. Participants with lower levels of perceived stress and higher flexible restraint were more likely to continue their WMA. Flexible restraint was a significant predictor of weight change. Interventions that promote flexibility in weight management may be beneficial for at-risk individuals under lockdown conditions.

Economic and health impacts of the Change4Life Food Scanner app: Findings from a randomized pilot and feasibility study

Introduction

The UK Government developed the Change4Life Food Scanner app to provide families with engaging feedback on the nutritional content of packaged foods. There is a lack of research exploring the cost-effectiveness of dietary health promotion apps.

Methods

Through stakeholder engagement, a conceptual model was developed, outlining the pathway by which the Food Scanner app leads to proximal and distal outcomes. The conceptual model informed the development of a pilot randomized controlled trial which investigated the feasibility and acceptability of evaluating clinical outcomes in children and economic effectiveness of the Food Scanner app through a cost-consequence analysis. Parents of 4–11 years-olds (n = 126) were randomized into an app exposure condition (n = 62), or no intervention control (n = 64). Parent-reported Child Health Utility 9 Dimension (CHU9D) outcomes were collected alongside child healthcare resource use and associated costs, school absenteeism and parent productivity losses at baseline and 3 months follow up. Results for the CHU9D were converted into utility scores based on UK adult preference weights. Sensitivity analysis accounted for outliers and multiple imputation methods were adopted for the handling of missing data.

Results

64 participants (51%) completed the study (intervention: n = 29; control: n = 35). There was a mean reduction in quality adjusted life years between groups over the trial period of –0.004 (SD = 0.024, 95% CI: –0.005; 0.012). There was a mean reduction in healthcare costs of –£30.77 (SD = 230.97; 95% CI: –£113.80; £52.26) and a mean reduction in workplace productivity losses of –£64.24 (SD = 241.66, 95% CI: –£147.54; £19.07) within the intervention arm, compared to the control arm, over the data collection period. Similar findings were apparent after multiple imputation.

Discussion

Modest mean differences between study arms may have been due to the exploration of distal outcomes over a short follow-up period. The study was also disrupted due to the coronavirus pandemic, which may have confounded healthcare resource data. Although measures adopted were deemed feasible, the study highlighted difficulties in obtaining data on app development and maintenance costs, as well as the importance of economic modeling to predict long-term outcomes that may not be reliably captured over the short-term.

Clinical trial registration

https://osf.io/, identifier 62hzt.

Evaluating the Change4Life Food Scanner app in reducing children's sugar intake: a randomised pilot and feasibility study

BACKGROUND

The Change4Life Food Scanner app displays nutritional information using visual images alongside traffic light labels. The app's effectiveness for improving dietary choices is unknown. This study investigated the feasibility and acceptability of evaluating the effectiveness of the Food Scanner app in reducing children's sugar intake in the UK.

METHODS

Adopting a non-blinded parallel trial design, we randomly assigned (1:1) 126 parents of children aged 4-11 years through block randomisation sequences into a 3-month intervention consisting of exposure to the Change4Life Food Scanner app (version 1.6; ie, the intervention group [n=62]) or no intervention (ie, the control group [n=64]). Participants completed baseline and 3-month post-intervention measures of dietary intake (3-day food diary) and trial acceptability measures. The intervention group completed fortnightly app engagement measures. Ethical approval was obtained by the University of Sheffield Research Ethics Committee (026380).

FINDINGS

64 (51%) of 126 participants completed the study (29 [45%] in the intervention group and 35 [55%] in the control group). 51 (80%) of 64 reported that the study was easy to complete and 62 (97%) found receiving task completion reminders helpful. App engagement decreased throughout the study (eg, mean engagement time was 18·01 min [SD 27·15] in week 2, and 6·76 min [11·56] in week 12). 18 (64%) of 28 participants reported high overall app acceptability; however, seven (25%) did not find the app helpful. 24 (86%) of 28 reported high acceptability for the app's use of sugar cube images, which were rated as easy to understand and useful to supplement front of package nutritional labels. Six (21%) of 28 did not find sugar cube images helpful and 20 (71%) had low acceptability of the app aiding food purchasing decisions. 45 (73%) of 62 were willing to continue with the study for a 12-month trial.

INTERPRETATION

Despite a high attrition rate, study procedures were considered acceptable by most participants. Acceptability of the Food Scanner app was varied, and participants did not find the app helpful for food purchases. Analysis of preliminary efficacy of the intervention is ongoing, which will inform design parameters for a future large-scale trial.

FUNDING

Wellcome Trust.

Methods for the economic evaluation of obesity prevention dietary interventions in children: A systematic review and critical appraisal of the evidence

OBJECTIVES

We aim to describe and provide a discussion of methods used to conduct economic evaluations of dietary interventions in children and adolescents, including long-term modelling, and to make recommendations to assist health economists in the design and reporting of such evaluations.

METHODS

A systematic review was conducted in 11 bibliographic databases and the grey literature with searches undertaken between January 2000 and December 2021. A study was included if it (1) was an economic evaluation or modelling study of an obesity-prevention dietary intervention and (2) targeted 2- to 18-year-olds.

RESULTS

Twenty-six studies met the inclusion criteria. Twelve studies conducted an economic evaluation alongside a clinical trial, and 14 studies modelled long-term health and cost outcomes. Four overarching methodological challenges were identified: modelling long-term impact of interventions, measuring and valuing health outcomes, cost inclusions and equity considerations.

CONCLUSIONS

Variability in methods used to predict, measure and value long-term benefits in adulthood from short-term clinical outcomes in childhood was evident across studies. Key recommendations to improve the design and analysis of future economic evaluations include the consideration of weight regain and diminishing intervention effects within future projections; exploration of wider intervention benefits not restricted to quality-of-life outcomes; and inclusion of parental or caregiver opportunity costs.

An Assessment of Behavior Change Techniques in Two Versions of a Dietary Mobile Application: The Change4Life Food Scanner

The Change4Life Food Scanner app is a UK Government dietary app designed to provide feedback on the nutritional content of packaged foods to parents and their children. To understand its intended mechanism of behavior change and how Behavior Change Technique (BCT) content evolves with app updates, this research aimed to map out the BCTs of two versions of the Change4Life Food Scanner app. Two coders undertook a descriptive comparative analysis of the use of BCTs in the Food Scanner app using the Behavior Change Technique Taxonomy [both the outdated (v1.6) and updated (v2.0) versions of the app were coded]. Results showed that both versions encompass the BCTs "goal setting (behavior)", "feedback on behavior", "social support (unspecified)", "instruction on how to perform behavior", "salience of consequences", "prompts/cues" and "credible source". The outdated version contained the BCT "behavior substitution" which had been dropped in the updated version. The updated version featured the additional BCTs "information about social and environmental consequences", "information about emotional consequences", "social reward" and "social incentive" and was comparatively more BCT intensive in terms of content and occurrence. The BCT content of the Food Scanner app resembles that of existing dietary apps and incorporates several BCTs which have previously been found to be effective. Future work to evaluate the effectiveness of the app is recommended. This will provide insight into whether the combination of BCTs used in the Change4Life Food Scanner app are effective in improving dietary choices.

Motivation to consume palatable foods as a predictor of body image dissatisfaction: Using the Power of Food Scale in a Brazilian sample

The Power of Food Scale (PFS) is a questionnaire for self-assessing the motivation to consume palatable foods, especially in environments where food is abundant and constantly available. This study aimed to a) assess the factorial structure of the PFS in a Brazilian sample and b) examine the relationship between the power of food and body image dissatisfaction and BMI. The PFS and Body Shape Questionnaire (BSQ) were applied to a sample of 300 adults. Data were analysed using confirmatory factor analysis. Composite reliability (CR) was used to verify factor reliability. A partial least squares structural equation model was used to verify the effect of the PFS score on body image dissatisfaction. The PFS had an adequate factorial structure in this Brazilian sample, showing three well-defined factors: food available (CR = 0.91), food tasted (CR = 0.84), and food present (CR = 0.87). The BSQ showed one reliable factor (CR = 0.97). The power of the food aggregate factor significantly predicted body mass index (β = 0.16; p = .01) and body image dissatisfaction (β = 0.46; p < .001). The effect size was small for body mass index (f² = 0.02) and medium for body image dissatisfaction (f² = 0.26). The food present factor also had a slightly higher average among the three PFS factors. Women had higher PFS scores than men. Understanding the role that this motivation plays in physical and psychological outcomes such as body dissatisfaction can contribute to developing treatment strategies and support health professionals' performance in clinical settings.

Are Dietitians With Obesity Perceived as Competent and Warm? Applying the Stereotype Content Model to Weight Stigma in Brazil

The aim of this study was to understand how dietitians' body size influences perceived competence and warmth, based on the Stereotype Content Model (SCM). Online data were collected from 1,039 Brazilians, who were either laypeople, registered dietitians, or nutrition students. Participants rated the competence and warmth dimensions of three dietitians who differed in sex, body weight, and age. Participants also indicated how likelythey would consult or recommend each dietitian for nutritional advice, and indicated their attitudes toward people with obesity (PWO) [using The Antifat Attitudes Test (AFAT)]. Laypeople attributed less competence and warmth to all profiles compared to dietitians and students (p < 0.001). Three clusters occupied the SCM warmth-by-competence space. However, the clusters were different among groups (laypeople, dietitians, and students). For lay participants, the woman without overweight, the older woman, and the older man were located in the high competence/medium warmth cluster. Meanwhile, the woman with obesity was located in the medium competence/high warmth cluster. The dietitians and students map found the woman with obesity and the older woman in a high competence and warmth cluster. In general, the woman with obesity, the man without obesity, and the older man can be classified as ambivalent stereotypes, the woman being perceived as more warm than competent and the men more competent than warm. Participants with high AFAT scores were less likely to consult or recommend to a family member a dietitian with obesity. This study contributes to identifying ambivalent stereotypes for dietitians. Dietitians with obesity can be seen as warm but less competent. Also, although less intense than laypeople, dietitians, and students exhibited weight stigma. These findings can foster important discussions about weight stigma and emphasize the need to increase population awareness about the causes of obesity.

Manipulated exposure to television-style healthy food advertising and children's healthy food intake in nurseries

The detrimental impact of currently disproportionate amounts of digital food advertising for processed foods high in sugar, salt, and fat (HSSF) on children's food intake and dietary health is well-documented. The potential of digital healthy food advertising to encourage healthy eating in children is much less researched. A pre-test post-test control group design was used to compare the effect of specifically designed, television-style advertisements for healthy food versus toys on 172 three-to seven-year-old children's exclusively healthy food intake (vegetable, fruit, whole-grain) in five nurseries in Germany. Within- and between-group comparisons demonstrated the effectiveness of healthy food advertising exposure to increase children's healthy food intake. Three exposures to a 1-min-advertisement for healthy food were sufficient to increase children's healthy food intake by as much as three portions. Children in the control condition ate less healthy foods following viewing of a control advertisement (a matched toy advertisement). We concluded that digital healthy food advertising is likely to increase children's healthy food intake sufficiently to help children meet daily recommended amounts of vegetables, fruit, or whole-grain bread, and that this encouragement may be required as decreases in healthy food intake were found when healthy foods were merely available.

Low craving control predicts increased high energy density food intake during the COVID-19 lockdown: Result replicated in an Australian sample

This research aimed to replicate a previous UK-based finding that low craving control predicts increased intake of high energy density foods (HED) during the COVID-19 lockdown, and extend this finding to adults living in Victoria, Australia. The study also assessed whether acceptance coping moderates the relationship between craving control and increased HED food intake, and examined the associations between trait disinhibition, perceived stress and changes to HED food intake. An online survey completed by 124 adults living in Victoria, Australia (total eligible n = 147; 38.5 ± 12.9 years) during the COVID-19 lockdown showed that 49% of participants reported increased overall food intake, and 21-29% reported increased intake of HED sweet and savoury foods during the COVID-19 lockdown. Of the eating behaviour traits assessed, low craving control was the only significant predictor of increased HED sweet and savoury food intake (cognitive restraint, disinhibition and emotional eating were non-significant predictors). Perceived stress was associated with reported increases in overall savoury and sweet snack intake, but was not significantly associated with changes to specific HED food groups (sweet and savoury). In this sample, acceptance coping did not significantly moderate the relationship between craving control and increased HED food intake. Based on these replicated findings, further trials should now consider interventions targeting craving control to promote controlled food intake in individuals at-risk of weight gain during the current COVID-19 and future potential lockdowns.

Susceptibility to increased high energy dense sweet and savoury food intake in response to the COVID-19 lockdown: The role of craving control and acceptance coping strategies

Emerging evidence indicates that for some people, the COVID-19 lockdowns are a time of high risk for increased food intake. A clearer understanding of which individuals are most at risk of over-eating during the lockdown period is needed to inform interventions that promote healthy diets and prevent weight gain during lockdowns. An online survey collected during the COVID-19 lockdown (total n = 875; analysed n = 588; 33.4 ± 12.6 years; 82% UK-based; mostly white, educated, and not home schooling) investigated reported changes to the amount consumed and changes to intake of high energy dense (HED) sweet and savoury foods. The study also assessed which eating behaviour traits predicted a reported increase of HED sweet and savoury foods and tested whether coping responses moderated this relationship. Results showed that 48% of participants reported increased food intake in response to the COVID-19 lockdown. There was large individual variability in reported changes and lower craving control was the strongest predictor of increased HED sweet and savoury food intake. Low cognitive restraint also predicted greater increases in HED sweet snacks and HED savoury meal foods. Food responsiveness, enjoyment of food, emotional undereating, emotional overeating and satiety responsiveness were not significant predictors of changes to HED sweet and savoury food intake. High scores on acceptance coping responses attenuated the conditional effects of craving control on HED sweet snack intake. Consistent with previous findings, the current research suggests that low craving control is a risk factor for increased snack food intake during lockdown and may therefore represent a target for intervention.

Priming food intake with weight control cues: systematic review with a meta-analysis

BACKGROUND

A growing number of studies suggest that exposure to cues which are associated with weight control can prime or prompt controlled food intake in tempting food environments. However, findings are mixed and understanding which types of cues and for whom such cues may be most effective is needed to inform subsequent research and societal applications. A systematic review and meta-analysis were conducted to evaluate the effects of exposure to weight control cues compared with control cues on food intake.

METHODS

PsycINFO, Medline, Embase and Web of Science were searched using key terms. Hedge's g was used to calculate effect sizes based on mean food intake, standard deviations and sample sizes extracted from relevant publications and, a random effects model was used for the meta-analysis.

RESULTS

Twenty-five articles consisting of 26 studies were eligible. Data from 25 studies (31 effect sizes) were available for the meta-analysis. Overall, weight control cues reduced food intake, albeit to a trivial effect (ES: -0.149, 95% CI: -0.271 to - 0.027). Subgroup analyses when studies which induced negative affect were removed showed that for individuals with strong weight control goals the effect was small-to-moderate (ES: -0.440, 95% CI: -0.718 to - 0.163), whereas for individuals with weak weight control goals this effect was trivial and non-significant (ES: 0.014, 95% CI: -0.249 to 0.278). Cue type and level of engagement did not significantly moderate the effect; however, specific cues (low-calorie foods and thin models) and attended engagement yielded significant effects. Caution is needed interpreting these findings as most studies were rated with high risk of bias and a number of studies could not be included in the subgroup analyses.

CONCLUSIONS

Based on the data available, weight control cues reduce food intake in individuals with strong weight control goals. Further research is needed to explore longer term effects of cue exposure and confirm underlying mechanisms. PROSPERO registry#CRD42016052396.

A Low Energy-Dense Diet in the Context of a Weight-Management Program Affects Appetite Control in Overweight and Obese Women

Background

Low energy-dense (LED) foods reduce energy intake (EI); whether this effect is sustained over time and during weight loss is unknown.

Objective

This trial examined the effects of LED compared with high energy-dense (HED) meals on appetite, EI, and control over eating in the laboratory and during a weight-management program that encourages unrestricted intake of LED foods [Slimming World, UK (SW)] compared with a self-led Standard Care program [NHS weight-loss plan (SC)].

Methods

Overweight and obese women [n = 96; mean ± SD age: 41.03 ± 12.61 y; mean ± SD body mass index (in kg/m2): 34.00 ± 3.61] were recruited from the SW or SC programs. Primary outcomes included appetite, food preferences (liking and wanting for LED and HED foods), cravings, and evening meal EI (LED, HED) in response to calorie-matched LED (≤0.8 kcal/g) and HED (≥2.5 kcal/g) breakfast and lunch meals. Probe-day tests were conducted at weeks 3 and 4 and repeated at weeks 12 and 13 in a within-day crossover design. Secondary outcomes, including body weight and program experience, were measured from weeks 1 to 14 in a parallel-group design. Dietary compliance was monitored with the use of weighed food diaries at weeks 3 and 12.

Results

Intention-to-treat (ITT) and completers analyses showed that the SW group lost more weight than the SC group [ITT: -5.9% (95% CI: -4.7%, -7.2%) compared with -3.5% (-2.3%, -4.8%), P < 0.05; completers: -6.2% (-4.8%, -7.6%) compared with 3.9% (-2.5%, -5.2%), P < 0.05]. The SW group reported greater control over eating and more motivation to continue the program compared with the SC group. LED meals increased sensations of fullness and reduced hunger on probe days (P < 0.001). Total-day EI was 1057 ± 73 kcal less (95% CI: 912, 1203 kcal; 36%) under LED compared with HED conditions (P < .001). Liking for LED and HED foods and wanting for HED foods were lower before lunch under LED compared with HED conditions, and liking decreased to a greater extent after the LED lunch. The SW group reported fewer cravings under LED compared with HED conditions (P < 0.05). On probe days, appetite and EI outcomes did not differ between weeks 3 and 12 or between the SW and SC groups.

Conclusion

LED meals improve appetite control in women attempting weight loss and the effect is sustainable. Consumption of LED meals likely contributed to weight loss in the SW program. This study was registered at clinicaltrials.gov as NCT02012426.

Slimming starters. Intake of a diet-congruent food reduces meal intake in active dieters

Dietary restraint is known to break down in the face of tempting foods. Previous research suggests exposure to cues associated with slimming such as images or odours act as prompts to restrict intake of a tempting snack in dieters. The effects of consuming diet-congruent foods on subsequent intake of a meal have not yet been investigated. Thus, using a repeated measures design 26 female participants (dieters or non-dieters) consumed a diet-congruent (100 kcal salad), hedonic (100 kcal garlic bread) or neutral (0 kcal water) preload. A lexical decision task measured the salience of diet and hedonic thoughts and participants were then offered pizza as a main meal. Appetite sensations were measured throughout the study. Compared to the hedonic and neutral preload, a diet-congruent preload reduced dieters' entire meal intake by 21%. In contrast, non-dieters consumed 9% more in the hedonic preload condition compared to the neutral preload, yet showed no differences between the diet-congruent and other conditions. Salad lowered participants desire to eat and increased fullness compared to garlic bread and water preloads. Dieters were also less hungry after the salad compared to the garlic bread and water preloads. Consuming a diet-congruent first course may prompt lower intake at a meal, in part due to facilitating resolve to refrain from overeating a tempting second course.

Pre-exposure to diet-congruent food reduces energy intake in restrained dieting women

Dietary restriction often fails in the face of tempting and palatable foods; however there is evidence that exposure to diet-congruent cues, such as foods associated with 'slimming' may facilitate control over food intake. The present study examined the effect of exposure to a diet-congruent food on subsequent energy intake in active dieters. Using a within-subjects design, restrained eaters who were currently on a diet (n = 13) and unrestrained non-dieters (n = 21) were exposed to a tempting food cue (chocolate) and a diet-congruent food cue (fruit orange) on two separate testing sessions, and subsequent snack intake was measured. Unrestrained non-dieters consumed similar amounts of snack food across conditions, whilst restrained dieters consumed 60% less chocolate (kcal) after exposure to the diet cue compared to the tempting cue. Exposure to a diet-congruent food cues may help dieters control energy intake when tempted by palatable food.