Habit formation of preventive behaviours during the COVID-19 pandemic: a longitudinal study of physical distancing and hand washing.

BACKGROUND: Since the outbreak of the COVID-19 pandemic, physical distancing and hand washing have been used as effective means to reduce virus transmission in the Netherlands. However, these measures pose a societal challenge as they require people to change their customary behaviours in various contexts. The science of habit formation is potentially useful for informing policy-making in public health, but the current literature largely overlooked the role of habit in predicting and explaining these preventive behaviours. Our research aimed to describe habit formation processes of physical distancing and hand washing and to estimate the influences of habit strength and intention on behavioural adherence. METHODS: A longitudinal survey was conducted between July and November 2020 on a representative Dutch sample (n = 800). Respondents reported their intentions, habit strengths, and adherence regarding six context-specific preventive behaviours on a weekly basis. Temporal developments of the measured variables were visualized, quantified, and mapped onto five distinct phases of the pandemic. Regression models were used to test the effects of intention, habit strength, and their interaction on behavioural adherence. RESULTS: Dutch respondents generally had strong intentions to adhere to all preventive measures and their adherence rates were between 70% and 90%. They also self-reported to experience their behaviours as more automatic over time, and this increasing trend in habit strength was more evident for physical-distancing than for hand washing behaviours. For all six behaviours, both intention and habit strength predicted subsequent adherence (all ps < 2e-16). In addition, the predictive power of intention decreased over time and was weaker for respondents with strong habits for physical distancing when visiting supermarkets (B = -0.63, p <.0001) and having guests at home (B = -0.54, p <.0001) in the later phases of the study, but not for hand washing. CONCLUSIONS: People's adaptations to physical-distancing and hand washing measures involve both intentional and habitual processes. For public health management, our findings highlight the importance of using contextual cues to promote habit formation, especially for maintaining physical-distancing practices. For habit theories, our study provides a unique dataset that covers multiple health behaviours in a critical real-world setting.

Investigating sex differences in psychological predictors of snack intake among a large representative sample.

OBJECTIVE: It is often assumed that there are substantial sex differences in eating behaviour (e.g. women are more likely to be dieters or emotional eaters than men). The present study investigates this assumption in a large representative community sample while incorporating a comprehensive set of psychological eating-related variables. DESIGN: A community sample was employed to: (i) determine sex differences in (un)healthy snack consumption and psychological eating-related variables (e.g. emotional eating, intention to eat healthily); (ii) examine whether sex predicts energy intake from (un)healthy snacks over and above psychological variables; and (iii) investigate the relationship between psychological variables and snack intake for men and women separately. Snack consumption was assessed with a 7d snack diary; the psychological eating-related variables with questionnaires. SETTING: Participants were members of an Internet survey panel that is based on a true probability sample of households in the Netherlands. SUBJECTS: Men and women (n 1292; 45 % male), with a mean age of 51·23 (sd 16·78) years and a mean BMI of 25·62 (sd 4·75) kg/m2. RESULTS: Results revealed that women consumed more healthy and less unhealthy snacks than men and they scored higher than men on emotional and restrained eating. Women also more often reported appearance and health-related concerns about their eating behaviour, but men and women did not differ with regard to external eating or their intentions to eat more healthily. The relationships between psychological eating-related variables and snack intake were similar for men and women, indicating that snack intake is predicted by the same variables for men and women. CONCLUSIONS: It is concluded that some small sex differences in psychological eating-related variables exist, but based on the present data there is no need for interventions aimed at promoting healthy eating to target different predictors according to sex.

Depletion sensitivity predicts unhealthy snack purchases.

The aim of the present research is to examine the relation between depletion sensitivity - a novel construct referring to the speed or ease by which one's self-control resources are drained - and snack purchase behavior. In addition, interactions between depletion sensitivity and the goal to lose weight on snack purchase behavior were explored. Participants included in the study were instructed to report every snack they bought over the course of one week. The dependent variables were the number of healthy and unhealthy snacks purchased. The results of the present study demonstrate that depletion sensitivity predicts the amount of unhealthy (but not healthy) snacks bought. The more sensitive people are to depletion, the more unhealthy snacks they buy. Moreover, there was some tentative evidence that this relation is more pronounced for people with a weak as opposed to a strong goal to lose weight, suggesting that a strong goal to lose weight may function as a motivational buffer against self-control failures. All in all, these findings provide evidence for the external validity of depletion sensitivity and the relevance of this construct in the domain of eating behavior.

'I ate too much so I must have been sad': Emotions as a confabulated reason for overeating.

BACKGROUND: Emotional eating (i.e., overeating in response to negative affect) is a commonly accepted explanation for eating behaviors that are not in line with personal eating-norms. However, the empirical evidence for a causal link between self-reported emotional eating and overeating is mixed. The present study tested an alternative hypothesis stating that high emotional eating scores are indicative of a susceptibility to use negative affect as a confabulated, post-hoc reason to explain overeating. METHODS: Female students (N = 46) participated in a 'taste-test' and came back to the lab a day later to receive feedback that they either ate too much (norm-violation condition) or an acceptable amount of food (control condition), whereafter emotional eating was assessed. Negative affect was measured several times throughout the study. RESULTS: In the norm-violation condition, participants with high emotional eating scores retrospectively rated their affect prior to eating as more negative than participants with low emotional eating scores. In the control condition, no effect of emotional score on affect ratings was found. DISCUSSION: For some individuals emotional eating scores may represent a tendency to retrospectively attribute overeating to negative affect. This could explain the lack of consistent findings for a link between self-reported emotional eating and overeating.

It's my party and I eat if I want to. Reasons for unhealthy snacking.

Investigating the reasons that people give for unhealthy snacking behavior is important for developing effective health interventions. Little research, however, has identified reasons that apply to a large audience and most studies do not integrate multiple factors, precluding any conclusions regarding their relative importance. The present study explored reasons for unhealthy snacking among a representative community sample. Participants (N = 1544) filled out the newly developed Reasons to Snack inventory assessing an elaborate range of motives at baseline and 1-month follow-up. Exploratory and replication factor analyses identified six categories: opportunity induced eating, coping with negative emotions, enjoying a special occasion, rewarding oneself, social pressure, and gaining energy. The highest mean scores were obtained for enjoying a special occasion and opportunity induced eating. Regression analyses with participant characteristics as independent variables and each category of reasons as dependent variables showed differences for age. For all reasons except to enjoy a special occasion, younger people reported a higher score. Women indicated a higher score than men on coping with negative emotions, enjoying a special occasion and gaining energy. People who diet to a stronger extent reported a higher score for snacking because of social pressure, to reward oneself and to cope with negative emotions, with the latter also being related to a higher BMI. Finally, a higher education was associated with enjoying a special occasion. Future health interventions could allocate more attention to diminishing unhealthy snacking with regard to the six identified categories, specifically focusing on enjoying a special occasion and opportunity induced eating.

Efficacy of a self-management intervention for weight control in overweight and obese adults: a randomized controlled trial.

Brief self-management interventions to engender successful weight maintenance are seldom tested in obese and overweight populations without diabetes. To test the efficacy of the intervention, aimed at improving proactive coping, in obese and overweight adults at risk for diabetes. Participants (N = 255) were randomly assigned to two experimental groups (N = 185) and a control group (N = 70). Experimental groups received the same intervention in week 1-8 (initial phase) and booster sessions with different content ("standard" vs. "relapse prevention") during week 9-24 (continuance phase). Primary outcomes were proactive coping, diet and Body Mass Index (BMI) at four time points (1 year between first and last measurement). Experimental groups improved in proactive coping during the initial phase and BMI during the continuance phase, whereas the control group did not. No differences emerged in diet. Brief self-management interventions can play a preventive role in chronic illnesses associated with obesity.

Health behavior interventions among people with lower socio-economic position: a scoping review of behavior change techniques and effectiveness.

Background: Behavior change interventions can unintendedly widen existing socio-economic health inequalities. Understanding why interventions are (in)effective among people with lower socio-economic position (SEP) is essential. Therefore, this scoping review aims to describe what is reported about the behavior change techniques (BCTs) applied within interventions and their effectiveness in encouraging physical activity and healthy eating, and reducing smoking and alcohol consumption according to SEP. Methods: A systematic search was conducted in 12 electronic databases, and 151 studies meeting the eligibility criteria were included and coded for health behavioral outcomes, SEP-operationalization, BCTs (type and number) and effectiveness. Results: Findings suggest that approaches for measuring, defining and substantiating lower SEP vary. Current studies of behavior change interventions for people of different SEP do not systematically identify BCTs, making systematic evaluation of BCT effectiveness impossible. The effectiveness of interventions is mainly evaluated by overall intervention outcomes and SEP-moderation effects are mostly not assessed. Conclusion: Using different SEP-operationalizations and not specifying BCTs hampers systematic evidence accumulation regarding effective (combinations of) BCTs for the low SEP population. To learn which BCTs effectively improve health behaviors among people with lower SEP, future intervention developers should justify how SEP is operationalized and must systematically describe and examine BCTs.

Dutch GPs' perspectives on addressing obesity: a qualitative study.

BACKGROUND: Early diagnosis and treatment of obesity in primary care may help to tackle the obesity pandemic. Nonetheless, GPs frequently fail to address obesity and demonstrate limited adherence to guidelines. AIM: To explore Dutch GPs' perspectives on addressing obesity regarding the following three target behaviours: discussing weight; diagnosing; and referring patients with obesity. DESIGN & SETTING: A qualitative focus group study with Dutch GPs. METHOD: Six focus groups were conducted with a purposive sample of 21 GPs. Thematic analysis was performed using deductive coding, according to the Theoretical Domains Framework (TDF). RESULTS: For discussing weight, the main barriers identified were a presented complaint unrelated to obesity (environmental context and resources), concerns about a negative response from the patient (beliefs about consequences), and worries about obesity being a sensitive subject to discuss (emotions). A long-term trustworthy relationship (social influences) facilitated discussing weight. For diagnosing patients with obesity, the main barriers were related to resources; for example, lack of (appropriate) measuring equipment and time (environmental context and resources). For referring patients with obesity, the main barriers were no referral options nearby (environmental context and resources), and doubts about the positive effects of the referral on weight change (beliefs about consequences). CONCLUSION: Different barriers for discussing weight, diagnosing, and referring patients with obesity were identified, underscoring the importance for tailored interventions to these specific behaviours. Improving knowledge and skills of GPs seems insufficient as this study showed that particular attention should be paid to establishing long-term relationships, addressing GPs' beliefs about consequences, and creating a supportive environment with sufficient time and resources.

The Development and Characteristics of Planetary Health in Medical Education: A Scoping Review.

PURPOSE: Climate change, biodiversity loss, and other ecological crises threaten human health globally. The interrelation between human health and ecosystems is addressed in the emerging field of planetary health. Ecological crises have created an urgency to integrate planetary health, including sustainable health care, into medical education. To facilitate integration and guide future research, this review aims to provide an overview of the existing literature about planetary health in medical education. METHOD: The authors conducted a scoping review using the conventional methodological framework for scoping studies. They performed a comprehensive search in 7 databases without language restrictions in March 2022. Two researchers independently extracted data. The team analyzed the data using data-driven thematic analysis, content analysis, and qualitative summarizing. Data were structured according to the Curriculum Development for Medical Education: A Six-Step Approach. RESULTS: The authors identified 3,703 unique publications, of which 127 were included. Articles predominantly (71%, n = 90) covered the call to integrate planetary health in medical education (step 1: general needs assessment). Many publications (24%, n = 31) proposed learning objectives (step 3); these mainly concerned raising awareness while few concerned action perspectives. Publications limitedly reported on the final steps of curriculum development. Only 2 covered a full cycle of curriculum development. Most were published recently, with first authors mainly from Europe and North America. CONCLUSIONS: Planetary health in medical education is an urgent and hot topic. Literature focused predominantly on why planetary health should be integrated in medical education and what should be covered. The authors recommend future research and education development to shift to how to do so, especially in evaluation and feedback. Research and education development needs to be conducted and reported on systematically and underpinned by educational principles. Lastly, it would benefit from perspectives beyond 'Western-based' ones.

Self-initiated lifestyle changes during a fasting-mimicking diet programme in patients with type 2 diabetes: a mixed-methods study.

BACKGROUND: Lifestyle changes, especially regarding diet quality and physical activity, are important in the management of type 2 diabetes (T2D). This mixed-methods study explores self-initiated lifestyle changes in patients with T2D who followed a periodic fasting-mimicking diet (FMD). METHODS: Quantitative data were obtained from the Fasting In diabetes Treatment trial (November 2018 to August 2021) in which 100 participants with T2D, using metformin only or no medication, were randomised to receive a monthly 5-day FMD for twelve months next to usual care, or usual care only. Diet quality and physical activity questionnaires were completed at baseline, six and twelve months. Changes over time were analysed using linear mixed models. Focus groups were organized with FMD participants to explore experiences regarding self-initiated lifestyle changes. The qualitative data was analysed using the Theoretical Domains Framework. RESULTS: Questionnaires were available from 49 FMD participants and 43 controls. No differences in diet quality were found. Total physical activity in the FMD participants changed from 34.6 to 38.5 h per week (h/wk) from baseline to twelve months, while in controls it changed from 34.9 to 29.0 h/wk (between group difference, p = 0.03). In six focus groups with FMD participants (n = 20), individual participants perceived the FMD as an encouragement for (minor) lifestyle changes. There were no barriers to behaviour change related to the FMD. Important facilitators of healthy behaviour were an increase in awareness of the impact of lifestyle on health (knowledge), better physical fitness (physical) and health improvement (reinforcement). Facilitators unrelated to the FMD included family support (social influences) and opportunities in the neighbourhood (environmental context and resources), while barriers unrelated to the FMD were experiencing health problems (physical) and social events (social influences). CONCLUSIONS: Using an FMD for five consecutive days per month did not affect diet quality in between FMD periods in quantitative analysis, but increased the number of hours per week spent on physical activity. Qualitative analysis revealed self-initiated improvements in both diet quality and physical activity in individual participants using an FMD. Healthcare professionals could use an FMD programme as a 'teachable moment' to stimulate additional lifestyle changes. TRIAL REGISTRATION: ClinicalTrials.gov; NCT03811587. Registered 22 January 2019.

In it for the long haul: characteristics of early and late drop out in a self-management intervention for weight control.

Although drop out rates in weight management interventions are high, little is known about characteristics of people dropping out at different time points during such interventions. This study aims to examine characteristics of early and late drop outs during a self-management intervention aimed at weight control, hypothesizing that changes in psychological characteristics during active intervention would differentiate drop outs from completers. Participants' (N = 167) socio-demographics and personality traits were measured via self-report at baseline, as well as their behavioral and psychological outcomes before and during the intervention. No baseline differences were found between early drop outs and initial completers. As expected, late drop outs were characterized by a different change pattern in self-efficacy during the initial phase compared to completers. Few differences in other characteristics were found. Changes in self-efficacy during active intervention are relevant for understanding drop out in weight management interventions.

Coping under pressure: employing emotion regulation strategies to enhance performance under pressure.

Performing under high pressure is an emotional experience. Hence, the use of emotion regulation strategies may prove to be highly effective in preventing choking under pressure. Using a golf putting task, we investigated the role of arousal on declined sport performance under pressure (pilot study) and the effectiveness of emotion regulation strategies in alleviating choking under pressure (main study). The pilot study showed that pressure resulted in decreased performance and this effect was partially mediated by increased arousal. The main study, a field study, showed that whereas the choking effect was observed in the control condition, reappraisal and, particularly, distraction were effective emotion regulation strategies in helping people to cope instead of choke under pressure. These findings suggest that interventions that aim to prevent choking under pressure could benefit from including emotion regulation strategies.

The effect of transparency on the temporal spillover effect of default nudges.

Previous studies show that the effects of (non-transparent) nudges can spill over to later similar decisions without nudges. In the current study, we aimed to determine whether such nudge temporal spillover effects are affected by making nudges transparent. The latter is recommended to (partly) mitigate ethical concerns surrounding the use of nudges. In two experiments, we nudged participants to complete a longer version of a survey. Participants were randomly assigned to either a control, a non-disclosed nudge (using a default to promote taking the longer survey) condition or a disclosed nudge (in which the use of the default nudge was explained) condition. In both Study 1 (N = 1270) and Study 2 (N = 1258) we observed a temporal spillover effect of the disclosed nudge, suggesting that transparency does not negatively affect the temporal spillover effect.

When nudgees become nudgers: Exploring the use of self-nudging to promote fruit intake.

The current study explored (1) the immediate and prolonged effects of self-nudges promoting fruit intake in the home environment, (2) whether the effect of self-nudges on fruit intake persists after self-nudges are no longer used (i.e. a temporal spillover effect) and (3) whether self-nudges can install healthy eating habits that, in turn, explain the temporal spillover effect. Participants (N = 331) were randomly assigned to either a control or self-nudge condition in which they had to choose a self-nudge promoting fruit consumption for 8 weeks. Thereafter, participants were asked to remove the self-nudge for 1 week to assess a possible temporal spillover effect. Results showed a positive effect of the self-nudges on fruit consumption right after implementation that continued during the 8 weeks in which the self-nudge was implemented, which was accompanied by an increase in fruit intake habit strength. However, a mixed picture emerged regarding the temporal spillover effect and no support was found for a mediation effect of habit strength. Although this study is only a first exploration of self-nudging to increase healthy food consumption, results indicate that self-nudging may be a promising extension of traditional nudging that can influence behaviour beyond out-of-home settings.

Beyond prevention: Regulating responses to self-regulation failure to avoid a set-back effect.

Despite having good intentions, people fail at times to self-regulate. Most of these instances of everyday self-regulation failure are in themselves trivial. However, the ensuing chain of attributions, thoughts, and subsequent behaviors that people experience after an instance of failure may be detrimental to their long-term self-regulation success. In two studies, we examined the potential of intervening in the aftermath of failure to prevent this so-called "setback effect" by instructing people that setbacks may occur and to attribute future incidents of failure to external causes. In Study 1, we tested whether the intervention indeed decreased the frequency of self-regulation failure in the context of dieting and procrastination. In Study 2, we aimed to replicate the findings from Study 1 in the context of procrastination, and we explored the mediating role of self-efficacy. In both studies, participants in the intervention condition experienced less self-regulation failure and more subjective self-regulation success in the days after the intervention. Study 2 demonstrated that this effect was partly mediated by an increase in self-efficacy. Taken together, findings suggest that a simple mindset manipulation promoting external attributions to failure may be effective in preventing a setback effect from occurring by protecting self-efficacy.

Spatiotemporal variations of public opinion on social distancing in the Netherlands: Comparison of Twitter and longitudinal survey data.

Background: Social distancing has been implemented by many countries to curb the COVID-19 pandemic. Understanding public support for this policy calls for effective and efficient methods of monitoring public opinion on social distancing. Twitter analysis has been suggested as a cheaper and faster-responding alternative to traditional survey methods. The current empirical evidence is mixed in terms of the correspondence between the two methods. Objective: We aim to compare the two methods in the context of monitoring the Dutch public's opinion on social distancing. For this comparison, we quantified the temporal and spatial variations in public opinion and their sensitivities to critical events using data from both Dutch Twitter users and respondents from a longitudinal survey. Methods: A longitudinal survey on a representative Dutch sample (n = 1,200) was conducted between July and November 2020 to measure opinions on social distancing weekly. From the same period, near 100,000 Dutch tweets were categorized as supporting or rejecting social distancing based on a model trained with annotated data. Average stances for the 12 Dutch provinces and over the 20 weeks were computed from the two data sources and were compared through visualizations and statistical analyses. Results: Both data sources suggested strong support for social distancing, but public opinion was much more varied among tweets than survey responses. Both data sources showed an increase in public support for social distancing over time, and a strong temporal correspondence between them was found for most of the provinces. In addition, the survey but not Twitter data revealed structured differences among the 12 provinces, while the two data sources did not correspond much spatially. Finally, stances estimated from tweets were more sensitive to critical events happened during the study period. Conclusions: Our findings indicate consistencies between Twitter data analysis and survey methods in describing the overall stance on social distancing and temporal trends. The lack of spatial correspondence may imply limitations in the data collections and calls for surveys with larger regional samples. For public health management, Twitter analysis can be used to complement survey methods, especially for capturing public's reactivities to critical events amid the current pandemic.

Do implementation intentions help to eat a healthy diet? A systematic review and meta-analysis of the empirical evidence.

OBJECTIVE: This systematic review and meta-analysis examined whether implementation intentions are an effective tool to help people put their intentions to eat a healthy diet into practice. Additionally, it was investigated whether the quality of the outcome measures and the quality of the control conditions that are used in these studies influence implementation intentions' effectiveness. METHODS: Twenty three empirical studies investigating the effect of implementation intentions on eating behavior were included. In assessing the empirical evidence, a distinction was made between studies that aim to increase healthy eating (i.e., eating more fruits) and studies that aim to diminish unhealthy eating (i.e., eating fewer unhealthy snacks). RESULTS: Implementation intentions are an effective tool for promoting the inclusion of healthy food items in one's diet (Cohen's d=.51), but results for diminishing unhealthy eating patterns are less strong (Cohen's d=.29). For studies aiming to increase healthy eating, it was found that higher quality outcome measures and lower quality control conditions tended to yield stronger effects. CONCLUSION: Implementation intentions are somewhat more effective in promoting healthy eating than in diminishing unhealthy eating, although for some studies promoting healthy eating effect sizes may have been inflated due to less than optimal control conditions.

The shaping role of hunger on self-reported external eating status.

As people are relatively incompetent in assessing the impact of visceral states on their behavior, two studies tested the hypothesis that hunger affects the extent to which people assess themselves as external eaters. In Study 1 participants' current self-reported hunger states were linked to their scores on an external eating scale. Hungrier participants perceived themselves more strongly as external eaters. In Study 2 hunger was experimentally manipulated, after which self-reported external eating was assessed. Hunger was found to affect people's self-reported external eating status, such that hungry participants scored higher and above the average norm score on external eating compared to satiated participants, who scored below this average norm score. The key implications of these findings are discussed.

The Effects of Nudges: One-Shot Only? Exploring the Temporal Spillover Effects of a Default Nudge.

Nudges, such as defaults, are generally found to be effective in guiding immediate behavioural decisions. However, little is known about whether the effect of a nudge can be lasting, meaning that it spills over to subsequent similar choices without the presence of a nudge. In three experiments, we explored the temporal spillover effects of a default nudge. The results of Experiments 1 (N = 1,077) and 2 (N = 1,036) suggest that nudging participants into completing a longer questionnaire affected their decision for the same behaviour a day later without the presence of a nudge. However, nudging participants into a healthier food choice in Experiment 3 (N = 969) did not result in such a temporal spillover effect. The results indicated that participants' change in attitude towards the nudged behaviour may partly explain the temporal spillover effects. These findings suggest that for some, but not all behaviours, default nudges may have the potential to yield temporal spillover effects and warrant a further investigation of boundary conditions and facilitators of the spillover effects of nudges.

The effect of nudges on autonomy in hypothetical and real life settings.

Nudges have repeatedly been found to be effective, however they are claimed to harm autonomy, and it has been found that laypeople expect this too. To test whether these expectations translate to actual harm to experienced autonomy, three online studies were conducted. The paradigm used in all studies was that participants were asked to voluntarily participate in a longer version of the questionnaire. This was either done in a hypothetical setting, where participants imagined they were asked this question, but did not answer it, and reported their expectations for autonomy; Or in an actual choice setting where participants answered the question and then reported their actual autonomy. The first study utilized the hypothetical setting and tried to replicate that laypeople expect nudges to harm autonomy with the current paradigm. A total of 451 participants were randomly assigned to either a control, a default nudge, or a social norm nudge condition. In the default nudge condition, the affirmative answer was pre-selected, and in the social norm nudge condition it was stated that most people answered affirmative. The results showed a trend for lower expected autonomy in nudge conditions, but did not find significant evidence. In Study 2, with a sample size of 454, the same design was used in an actual choice setting. Only the default nudge was found to be effective, and no difference in autonomy was found. In Study 3, Studies 1 and 2 were replicated. Explanation of the nudge was added as an independent variable and the social norm nudge condition was dropped, resulting in six conditions and 1322 participants. The results showed that participants indeed expected default nudges to harm their autonomy, but only if the nudge was explained. When actually nudged, no effect on autonomy was found, independent of the presence of an explanation.