Personal protective behaviors in response to COVID-19: a longitudinal application of protection motivation theory.

Introduction: Disease outbreaks are expected to occur more frequently and spread more rapidly in the age of globalization. Personal protective behaviors strongly affect infection and death rates worldwide. It is therefore of prime importance to better understand which factors predict personal protective behaviors during a pandemic. Protection motivation theory (PMT) proposes that people's motivation to protect themselves is based on two appraisal processes: threat appraisal and coping appraisal. Building on PMT, this longitudinal study aimed to predict personal protective behaviors in response to COVID-19, including hand hygiene, physical distancing, and mask wearing. Method: In the first wave of the study (November, 2020), the two appraisal processes as specified in PMT as well as intentions to perform protective behaviors were assessed in a representative sample of German adults (N = 328). In the second wave of this study, which was conducted one month later, the frequency of protective behaviors was measured. Structural equation modeling was used to test whether threat and coping appraisal predicted intentions and protective behaviors. Results: Response rate for the second wave was high (87%). For all three behaviors, self-efficacy predicted intentions and also indirectly behavior (i.e., mediated via intentions). Furthermore, exploratory tests of alternative theoretical models suggested that both self-efficacy and costs have direct effects (i.e., independent from their relationship with intentions) on performed behavior. Conclusion: To support individuals to engage in protective behaviors during a pandemic, it is important to reduce barriers to action and to foster individuals' self-efficacy.

A Smartphone-Based Implicit Theories Intervention for Health Behavior Change: Randomized Trial.

BACKGROUND: Implicit theories of health describe individuals' beliefs about the malleability of health. Individuals with an incremental theory of health believe that health, in general, is malleable, whereas individuals with an entity theory of health endorse the idea that health is largely fixed and predetermined. Previous research has shown that an incremental theory of health is associated with beneficial health outcomes and behaviors. A mobile health implicit theories intervention could be an effective way to increase health-promoting behaviors in the general population. OBJECTIVE: The aim of this study was to estimate the effect of a smartphone-based intervention designed to promote an incremental theory of health on the frequency of health-promoting behaviors in everyday life. The study used ecological momentary assessment to measure health behavior change. METHODS: This 2-arm, single-blind, delayed intervention design included 149 German participants (mean age 30.58, SD 9.71 years; n=79 female). Participants were asked to report their engagement in 10 health-promoting behaviors throughout the day for 3 weeks. Participants were randomly assigned to either an early intervention group (n=72) or a delayed intervention group (n=77). The intervention materials, designed to promote an incremental theory of health, were provided to participants after 1 week (early intervention group) or 2 weeks (delayed intervention group) of baseline behavior measurement. Data for this study were collected between September 2019 and October 2019. RESULTS: A paired-samples 2-tailed t test revealed that participants reported a stronger incremental theory after responding to the intervention materials (mean 5.58, SE 0.07) compared with incremental theory measured in an entry questionnaire (mean 5.29, SE 0.08; t148=4.07, SE 0.07; P<.001; 95% CI 0.15-0.43; d=0.33). Multilevel analyses showed that participants reported engaging in health-promoting behaviors more often after being presented with the intervention materials compared with baseline across conditions (b=0.14; t146.65=2.06, SE 0.07; P=.04; 95% CI 0.01-0.28). However, when the analysis was conducted separately for the early and delayed intervention groups, the intervention effect was only significant for the delayed intervention group (b=0.27; t1492.37=3.50, SE 0.08; P<.001; 95% CI 0.12-0.42). There was no significant increase in health-promoting behaviors for the early intervention group (b=0.02; t69.23=0.14, SE 0.11;P=.89; 95% CI -0.2 to 0.23). CONCLUSIONS: This study suggests that a smartphone-based intervention designed to promote an incremental theory of health is a cost- and time-effective approach to increase the frequency of engaging in health-promoting behaviors. However, research is needed to understand the reasons for the difference in intervention effects between the early and delayed intervention groups. The results of this study can guide the development of future digital health interventions that focus on implicit theories to promote health behavior change. TRIAL REGISTRATION: DRKS - German Clinical Trials Register DRKS00017379; https://drks.de/search/de/trial/DRKS00017379.

What motivates German consumers to reduce their meat consumption? Identifying relevant beliefs.

High levels of meat consumption cause problems related to public health, the environment, and animal welfare. Therefore, it is crucial to improve our understanding of the drivers and barriers involved in reducing meat consumption. Using the Theory of Planned Behavior (TPB), we examined to what extent attitude, subjective norm, and perceived behavioral control (PBC) affect intention and willingness to reduce meat consumption. In line with the TPB and going beyond existing literature, we also explored which specific beliefs determine these three constructs. In 2021, we conducted an online survey with a sample representative of the German population (N = 1093). Hierarchical regression models revealed that after controlling for sociodemographic characteristics, the TPB constructs explained 55% of the variance in intention and 61% of the variance in willingness. Importantly, each of the three TPB constructs affected intention and willingness to reduce meat consumption, with attitude having the largest impact. Habit strength and past behavior in addition to the TPB constructs did not improve prediction. Multiple linear regression models showed that attitude was determined by the beliefs that reducing meat consumption leads to a healthier diet, a reduced risk of developing certain diseases, a more natural diet, and the feeling of missing meat. In contrast, environmental and animal welfare concerns showed no significant effect on attitude. Both family and friends contributed to the perceived social pressure. The beliefs of being able to prepare meat-free meals, having enough time to spend on one's diet, and being able to easily purchase meat substitutes led to higher PBC. Based on these findings, we provide recommendations for intervention strategies and derive implications for future research.

Trends in educational disparities in preventive behaviours, risk perception, perceived effectiveness and trust in the first year of the COVID-19 pandemic in Germany.

BACKGROUND: Educational disparities in health and health behaviours have always been relevant in public health research and are particularly challenging in the context of the COVID-19 pandemic. First studies suggest that factors important for the containment of the COVID-19 pandemic, such as prevention behaviour, risk perception, perceived effectiveness of containment measures, and trust in authorities handling the pandemic, vary by educational status. This study builds on recent debate by examining trends in absolute and relative educational disparities in these factors in the first year of the COVID-19 pandemic in Germany. METHODS: Data stem from four waves of the GESIS Panel surveyed between March and October 2020 in Germany (15,902 observations from 4,690 individuals). Trends in absolute and relative disparities were examined for preventive behaviour, risk perception, perceived effectiveness of COVID-19 containment measures, and trust in individuals and institutions handling the COVID-19 pandemic by educational status using sex, age, residence, nationality, children under 16 living in household, family status, household size, the Big Five Inventory, and income class as control factors. Descriptive statistics as well as unadjusted and adjusted linear regression models and random effects models were performed. RESULTS: We observed an initially rising and then falling trend in preventive behaviour with consistent and significant absolute and relative disparities with a lower preventive behaviour among low educated individuals. Indication of a U-shaped trend with consistent significantly lower values among lower educated individuals was found for risk perception, whereas perceived effectiveness and trust decreased significantly over time but did not significantly vary by educational status. CONCLUSIONS: Results indicate persistent educational disparities in preventive behaviour and risk perception and a general decline in perceived effectiveness and trust in the first year of the COVID-19 pandemic in Germany. To address this overall downward trend and existing disparities, comprehensive and strategic management is needed to communicate the risks of the pandemic and the benefits of COVID-19 containment measures. Both must be adapted to the different needs of educational groups in particular in order to overcome gaps in preventive behaviour and risk perception by educational status.

White Paper: Open Digital Health - accelerating transparent and scalable health promotion and treatment.

In this White Paper, we outline recommendations from the perspective of health psychology and behavioural science, addressing three research gaps: (1) What methods in the health psychology research toolkit can be best used for developing and evaluating digital health tools? (2) What are the most feasible strategies to reuse digital health tools across populations and settings? (3) What are the main advantages and challenges of sharing (openly publishing) data, code, intervention content and design features of digital health tools? We provide actionable suggestions for researchers joining the continuously growing Open Digital Health movement, poised to revolutionise health psychology research and practice in the coming years. This White Paper is positioned in the current context of the COVID-19 pandemic, exploring how digital health tools have rapidly gained popularity in 2020-2022, when world-wide health promotion and treatment efforts rapidly shifted from face-to-face to remote delivery. This statement is written by the Directors of the not-for-profit Open Digital Health initiative (n = 6), Experts attending the European Health Psychology Society Synergy Expert Meeting (n = 17), and the initiative consultant, following a two-day meeting (19-20th August 2021).

Development and Validation of the Diet-Related Beliefs of Exercisers Scale.

Many exercise-based weight-loss interventions result in considerably less weight loss than predicted. One possible explanation could be that people have certain beliefs about the interplay of exercise and food that also influence their eating behavior, such as the belief that food is a reward for exercise. The current research outlines a systematic multiphase process to develop a psychometrically sound scale to assess these beliefs. In Study 1, regular exercisers (N = 520) completed an exploratory questionnaire on their beliefs related to diet and exercise. In Study 2 (N = 380), the factor structure of the newly developed scale was corroborated by confirmatory factor analysis. In addition, a test-retest (N = 166) was used to confirm reliability and stability. In sum, the Diet-Related Beliefs of Exercisers Scale with its four subscales ("Refrain from Eating," "Food as Reward," "Healthy Eating," and "Nutritional Replenishment") represents a valid and reliable measure of exercisers' diet-related beliefs.

Egocentric social network correlates of physical activity.

BACKGROUND: The social environment might play an important role in explaining people's physical activity (PA) behavior. However, little is known regarding whether personal networks differ between physically active and physically inactive people. This study aimed to examine the relationship between personal network characteristics and adults' physical (in)activity. METHODS: An egocentric social network study was conducted in a random sample in Switzerland (n = 529, mean age of 53 years, 54% females). Individual and personal network measures were compared between regular exercisers and non-exercisers. The extent of these factors' association with PA levels was also examined. RESULTS: Non-exercisers (n = 183) had 70% non-exercising individuals in their personal networks, indicating homogeneity, whereas regular exercisers (n = 346) had 57% regularly exercising individuals in their networks, meaning more heterogeneous personal networks. Additionally, having more regular exercisers in personal networks was associated with higher PA levels, over and above individual factors. Respondents with an entirely active personal network reported, on average, 1 day of PA more per week than respondents who had a completely inactive personal network. Other personal network characteristics, such as network size or gender composition, were not associated with PA. CONCLUSION: Non-exercisers seem to be clustered in inactive networks that provide fewer opportunities and resources, as well as less social support, for PA. To effectively promote PA, both individuals and personal networks need to be addressed, particularly the networks of inactive people (e.g., by promoting group activities).

Consumer perception and behaviour related to low-alcohol wine: do people overcompensate?

OBJECTIVE: Compared with standard wines, low-alcohol wines may have several social and health benefits. Innovative production processes have led to high-quality light wines. It is, however, unclear how consumers perceive and consume these alcohol-reduced wines. The current study aimed to investigate how people evaluate low-alcohol wine (Sauvignon Blanc) and if the reduction in alcohol and the information that a wine is low in alcohol influences consumption. DESIGN: Randomised controlled trial (RCT). SETTING: Participants were invited to a wine tasting and randomised into one of the three conditions: they either tasted a 'new white wine' (12·5 % alcohol content), a 'new low-alcohol white wine' (8·0 % alcohol content) or they tasted the low-alcohol wine but were not aware that the wine was reduced in alcohol (low-alcohol, blinded). PARTICIPANTS: Ninety participants (42 % male, mean age = 41 (sd 14) years). RESULTS: Mean comparisons showed similar ratings for the low-alcohol conditions and the standard alcohol condition (mean > 5·6/7). The mean consumed amount across all conditions did not differ (162 (sd 71) ml, (F2,86 = 0·43, P > 0·05)), hence people who tasted the low-alcohol wine consumed approximately 30 % less alcohol. However, participants were willing to pay more for the normal wine compared with the low-alcohol wine, (F2,87 = 3·14, P < 0·05). CONCLUSIONS: Participants did not alter their drinking behaviour in response to the reduced alcohol content, and the low-alcohol wine was perceived positively. There might be an emerging market potential for wine of reduced alcohol content, but consumers may not be willing to pay the same price as for the standard wine.

Is your health malleable or fixed? The influence of implicit theories on health-related attitudes and behaviour.

Objective: Implicit theories of health describe the extent to which health is perceived as a fixed (entity theory) versus malleable (incremental theory) characteristic. In four studies, it was investigated how these theories correspond to health-related attitudes and behaviours.Design: In Study 1 (N = 130), the relationship of implicit theories of health and health-related behaviours was assessed via self-reports. To investigate their causal influence on health-related attitudes (Study 2; N = 357) and hypothetical food choices (Study 3; N = 351), implicit theories of health were manipulated using fictitious newspaper articles. In Study 4 (N = 235), the relationship of implicit theories and health behaviours in daily life was investigated using experience sampling.Results: Study 1 showed that a stronger incremental theory is positively associated with health behaviours like eating healthily or engaging in physical activity. Studies 2 and 3 revealed that a manipulation of implicit theories of health changes health-related attitudes and hypothetical food choices via an internal health locus of control. Study 4 showed that individuals with a stronger incremental theory reported more health-promoting behaviours in daily life.Conclusion: These findings extend the knowledge about implicit theories as they show that they are highly relevant for health promotion.

The Multiple Food Test: Development and validation of a new tool to measure food choice and applied nutrition knowledge.

Assessing individual food choices within health and nutrition related research is challenging and there is a strong need for valid and reliable instruments. In this paper, we introduce the Multiple Food Test as a new tool for measuring food choices and applied nutrition knowledge. The Multiple Food Test has the format of an image selection task. Part one of the Multiple Food Test consists of 18 trials in which participants are presented with sets of four food items and asked to choose one item they would prefer to consume (choice scale). In part two, participants saw the same 18 trials and were asked to indicate which of the items presented they perceived as being the healthiest (applied knowledge scale). Results across three studies (total N = 666) indicate that both subscales of the Multiple Food Test have good psychometric properties. Healthier choices were significantly associated with implicit theories of health, healthy eating frequency and importance (Study 1), a stronger health versus taste motive (Study 1 and 2), self-control, and habitual fruit and vegetable intake (Study 2). In Study 3, choices in the Multiple Food Test positively predicted actual food choices. The applied knowledge scale showed agreement with an existing nutrition knowledge scale, and higher scores were associated with higher levels of self-control (Study 2). The Multiple Food Test presents new opportunities to evaluate underlying variables and interventions that influence food choice or eating behavior.

Crowdsourcing hypothesis tests: Making transparent how design choices shape research results.

To what extent are research results influenced by subjective decisions that scientists make as they design studies? Fifteen research teams independently designed studies to answer five original research questions related to moral judgments, negotiations, and implicit cognition. Participants from 2 separate large samples (total N > 15,000) were then randomly assigned to complete 1 version of each study. Effect sizes varied dramatically across different sets of materials designed to test the same hypothesis: Materials from different teams rendered statistically significant effects in opposite directions for 4 of 5 hypotheses, with the narrowest range in estimates being d = -0.37 to + 0.26. Meta-analysis and a Bayesian perspective on the results revealed overall support for 2 hypotheses and a lack of support for 3 hypotheses. Overall, practically none of the variability in effect sizes was attributable to the skill of the research team in designing materials, whereas considerable variability was attributable to the hypothesis being tested. In a forecasting survey, predictions of other scientists were significantly correlated with study results, both across and within hypotheses. Crowdsourced testing of research hypotheses helps reveal the true consistency of empirical support for a scientific claim. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Introducing functional and dysfunctional self-licensing: Associations with indices of (un)successful dietary regulation.

OBJECTIVE: Giving in to food temptations is typically labeled as self-regulation failure. However, when indulgence stems from self-licensing processes, that is, relying on reasons to justify diet deviations, these instances might actually promote successful goal striving. This research aimed to theoretically define and test under what conditions self-licensing would be considered functional (e.g., when it ultimately serves the long-term goal of weight control) and dysfunctional (e.g., when it threatens successful goal striving). METHOD: First, a pool of items reflecting functional and dysfunctional ways of self-licensing was tested and representative items were selected (Study 1; N = 194). Next, their classification was corroborated by examining the associations with indices of (un)successful dietary regulation (Study 2; N = 147). Finally, it was tested whether (dys)functional self-licensing predicted unhealthy snack intake, by means of participants keeping an unhealthy snack diary (Study 3; N = 54). RESULTS: The theorized distinction was confirmed, and the obtained correlational patterns supported the proposed (dys)functionality of the two types of self-licensing. Importantly, results showed that dysfunctional self-licensing predicted higher snack intake, whereas functional self-licensing predicted lower snack intake. CONCLUSION: The present studies provide evidence for the existence of two types of self-licensing, and thereby contribute to theoretical development.

Consistency and Balancing in Everyday Health Behaviour: An Ecological Momentary Assessment Approach.

BACKGROUND: Little is known about the sequential interplay of different health behaviours. Health behaviours may be connected in four different ways: a healthy behaviour may lead to a subsequent healthy or unhealthy behaviour (positive consistency and licensing, respectively), or an unhealthy behaviour may lead to a subsequent unhealthy or healthy behaviour (negative consistency and cleansing, respectively). In this study, these four possible types of sequential health behaviours were examined jointly in people's daily life. METHODS: The study used ecological momentary assessment. Participants (N = 235; 55% female; age 18-45) were randomly signalled five times daily on their smart phones for seven consecutive days. They reported both healthy and unhealthy behaviours that occurred within the past hour. Participants were also asked if the (healthy or unhealthy) behaviour was related to any previous healthy or unhealthy behaviour. In addition, they completed measures of life satisfaction, general health status, and compensatory health beliefs. RESULTS: Positive consistency predicted satisfaction with life, whereas negative consistency and cleansing negatively predicted general health status. Compensatory health beliefs were not related to actual cleansing or licensing behaviour. CONCLUSIONS: Fostering positive consistency and discouraging cleansing behaviour should play a pivotal role in health promotion programmes.

Executive functions and the self-regulation of eating behavior: A review.

In order to pursue the long-term goal of losing weight, a dieter needs to resist the urge to eat appealing, tasty foods. Beside sufficient motivation to resist these foods, dieters also need the capacity for successful self-regulation, and this capacity is strongly related to executive functions. Executive function is an umbrella term encompassing a number of interrelated higher-order cognitive processes that allow people to take goal-directed action. In this review, we outline how basic facets of executive functioning (updating, inhibiting, and shifting) contribute to the successful self-regulation of eating behavior. Moreover, we identify aspects of the self-regulation of eating behavior that are still under-researched. We conclude by outlining the implications of the extant research for intervention strategies and the design of future research studies on the role of executive functions for the self-regulation of eating behavior.

The dark side of fluency: Fluent names increase drug dosing.

Prior research has demonstrated that high processing fluency influences a wide range of evaluations and behaviors in a positive way. But can high processing fluency also lead to potentially hazardous medical behavior? In 2 controlled experiments, we demonstrate that increasing the fluency of pharmaceutical drug names increases drug dosage. Experiment 1 shows that drugs with fluent names are perceived as safer than those with disfluent names and this effect increases drug dosage for both synthetically produced and herbal drugs. Experiment 2 demonstrates that people chose a higher dosage for themselves and for a child if the drug bears a fluent (vs. disfluent) name. Using linear regression based mediation analysis, we investigated the underlying mechanisms for the effect of fluency on risk perception in more detail. Contrary to prior research, we find that affect, but not familiarity, mediates the fluency-risk link. Our findings suggest that a drug name's fluency is a powerful driver of dosing behavior. (PsycINFO Database Record

Whether people believe that overweight is unhealthy depends on their BMI.

An online experiment with 536 participants was conducted to investigate how people who differ in body weight perceive scientific information on body weight and mortality. The results showed that individuals who were aware that they are overweight were more inclined to trust a study that showed that overweight reduces mortality (P < 0.001). This finding is relevant as the BMI-mortality association remains a matter of scientific and public debate and people's risk perceptions influences their willingness to change behaviour.

Putting knowledge into practice: Does information on adverse drug interactions influence people's dosing behaviour?

OBJECTIVE: Adverse drug events relating to drug-drug interactions are a common cause of patient harm. Central to avoiding this harm is the patients' understanding that certain drug combinations present a synergistic risk. Two studies tested whether providing individuals with information about a drug combination that presents a synergistic (cf. additive) risk would elicit higher perceived risk and, therefore, would result in greater precaution in terms of dosing behaviour. DESIGN: Both studies employed an experimental design. METHODS: Participants were presented with a scenario describing how two symptoms of an infection could each be treated by a different drug. In Experiment 1, information about the effects of combining the two drugs was varied: (1) no information, (2) combination elicits an additive risk, or (3) combination elicits a synergistic risk. In Experiment 2, the size of the risk (small or large) and the participant's role (patient or doctor) was also varied. RESULTS: In both experiments, perceived risk and negative affect increased in response to information about the increased probability of side effects from the drug-drug interaction. Despite these increases, participants did not adjust their drug dosing behaviour in either experiment: Dosing was similar when these interactions were large or small, or when they were due to synergistic or additive effects. CONCLUSIONS: People may struggle to transfer their knowledge of drug-drug interaction risks into decision-making behaviours. Care should be taken not to assume that holding accurate risk perceptions of a drug's side effect will result in decisions that help avoid adverse drug events. Statement of contribution What is already known on this subject? Adverse effects of drug-drug interactions are a cause of hospital admissions and increase morbidity and mortality. Patients' understanding that certain drug combinations present a synergistic risk is crucial to avoid harm. It is not clear whether synergistic drug interactions increase risk perception and influence dosing decisions. What does this study add? Perceived risk and negative affect increased in response to synergistic risk information. Despite these increases, participants did not adjust their drug dosing behaviour. People struggle to transfer their knowledge of drug-related risks into behavioural decisions.

Toward a mechanistic understanding of the impact of food insecurity on obesity.

Nettle et al. provide a useful but incomplete analysis of the drivers of obesity. In this commentary, we argue that a dual-motives conceptualization of self-control, together with insights from the psychology of (perceived and actual) scarcity, might help advance a more fine-grained mechanistic understanding of the observed association between food insecurity and obesity.

Towards an understanding of adult judgments of synergistic health benefits.

OBJECTIVE: Numerous scientific studies show that certain combinations of dietary and/or lifestyle factors produce health benefits which are greater than the sum of the benefits associated with each factor alone. To address an existing knowledge gap, we assessed the extent to which individuals understand that certain combinations present these 'synergistic health benefits'. DESIGN: Health benefit judgments were obtained from lay adults for a range of dietary and/or lifestyle combinations that have been found to present synergistic benefits. Association between these judgments and socio-cognitive characteristics such as numeracy, education, and health interest (HI) were examined. METHODS: Three hundred and fifty-two Swiss adults were presented with a description of one of eight synergistically beneficial combinations. Each participant provided a categorical benefit judgment (i.e., subadditive, additive, or synergistic) for the combination and explained the cognitive reasoning underlying their judgment. Participants completed measures of numeracy and HI. RESULTS: The proportion of combinations judged to present a synergistic benefit was modest for 'macro-level' combinations (e.g., diet and exercise), but low for 'micro-level' combinations (e.g., two phytochemicals). Cognitive reasoning data showed that a higher proportion of judgments for micro-level (cf. macro-level) combinations were based on greater subjective epistemic uncertainty. Higher interest in health was associated with a better understanding of synergistic benefits, but numeracy and education level were not. CONCLUSIONS: There is considerable scope to improve the extent to which lay adults understand that specific combination of diet and lifestyle behaviours can synergistically benefit their health. Our results enable us to make informed recommendations for public health interventions. STATEMENT OF CONTRIBUTION: What is already known on this subject? Combining certain dietary and/or lifestyle factors can result in synergistic health benefits. People could maintain/enhance their health by combining these synergistic combinations. No previous studies have assessed the extent to which people understand that certain factors produce synergistic health benefits. What does this study add? This is the first study to identify that lay awareness of synergistic health benefits could be substantially improved. Neither education level nor numeracy moderate judgments of synergistic benefits, but health interest does. Individuals better understand that broad lifestyle behaviours (cf. specific foods and phytochemicals) are synergistic.

Does self-prepared food taste better? Effects of food preparation on liking.

OBJECTIVE: The aim was to examine whether self-preparation of food increases the liking of healthy and unhealthy foods. METHOD: The study used a 2 (preparation: self-prepared vs. other-prepared) × 2 (healthiness: healthy vs. unhealthy) between-subjects design. Female participants (N = 120) tasted food that was either self-prepared or other-prepared, and that either contained markedly healthy or unhealthy ingredients. Interindividual differences in dietary restraint were also assessed. Liking and perceived healthiness of the food served as the main dependent variables. RESULTS: A significant interaction effect of food preparation and healthiness of the food on liking was revealed: Self-preparation increased the liking of the healthy but not of the unhealthy food. This effect was particularly strong for individuals with high levels of dietary restraint. Moreover, the combined effect of food preparation and healthiness of the food on liking was mediated by perceived healthiness of the food. CONCLUSION: The results bolster public health programs trying to encourage people to eat less prepared ready-to-eat foods and more self-prepared food. Because time available for home food preparation is often limited, programmatic efforts to encourage food preparation could be extended to schools and workplaces.