Relationship between attentional bias and stimulus control: An observational study of real-world eating patterns.

BACKGROUND: Attentional bias towards food related stimuli has been proposed as a potential target for dieting intervention, however the evidence supporting a relationship between attentional bias and food intake is mixed. Theory holds that food related attentional bias should be positively associated with measures of stimulus-controlled eating, and that implicit processes such as impulsivity moderate this association. The aim of the present study was to examine whether the proposed relationship between food-related attentional bias and stimulus control exists, and whether it is moderated by impulsivity. METHOD: A community sample of 68 participants completed a food-related attentional bias task and impulsiveness scale during a laboratory visit, after which they recorded their real-world eating in real-time over 14 days using Ecological Momentary Assessment (EMA). During this time, participants also responded to 4-5 randomly timed assessments per day. Food outlet presence (e.g., fast food restaurants, cafes, corner stores etc.) was assessed during both eating and non-eating assessments. EMA data was then used to determine levels of stimulus controlled eating for each participant. FINDINGS: Substantial variation was seen in both our measure of both food-related attentional bias (Range: 33.9 to 80.0) and in the degree to which the participant's eating could be categorised as being under stimulus control (Range: 0.50 to 0.93). However, food-related attentional bias scores were not a significant independent predictor of stimulus control and nor was this relationship moderated by impulsivity. CONCLUSION: Contrary to theoretical predictions, we found no evidence that of an association between attentional bias, impulsivity, and stimulus control. More work is needed to better understand the implicit processes underlying eating behaviour in the real-world.

Comfort eating: An observational study of affect in the hours immediately before, and after, snacking.

OBJECTIVE: 'Comfort eating' has been used to explain real-world food choices, suggesting that individuals are drawn to energy-dense ('unhealthy') snacks when experiencing negative affect. However, this concept has rarely been studied, particularly in real-world settings. Similarly, the effects of snacking on subsequent affect are also poorly understood. The present study aimed to examine the association between affect and snacking in daily life. METHODS: One hundred and forty-one adults recorded their food intake in real time for ~14 days using a study issued mobile phone. Participants also responded to randomly timed assessments. During both types of assessments, participants indicated their current level of affect. By anchoring off snacking events, the trajectory of affect in the hours leading up to - and following - snacking was explored. RESULTS: In the three hours leading up to a healthy snack, affect was stable. In contrast, affect fell during the hours leading up to an unhealthy snack. The interaction between snack type and time was significant. A similar, but opposite, pattern was seen following snacking: where affect decreased after unhealthy snacking, affect increased following healthy snack intake. CONCLUSION: The findings are consistent with the hypothesis of comfort eating, with unhealthy snacking being preceded by worsening affect. Unhealthy snacking did not, however, lead to affect improvements afterwards, which questions the 'effectiveness' of comfort eating. The intake of healthy snacks however was associated with positive affective experiences. These findings could function as a component of interventions aiming at improving dietary behaviours.

Comparison of Geographic Information System and Subjective Assessments of Momentary Food Environments as Predictors of Food Intake: An Ecological Momentary Assessment Study.

BACKGROUND: It has been observed that eating is influenced by the presence and availability of food. Being aware of the presence of food in the environment may enable mobile health (mHealth) apps to use geofencing techniques to determine the most appropriate time to proactively deliver interventions. To date, however, studies on eating typically rely on self-reports of environmental contexts, which may not be accurate or feasible for issuing mHealth interventions. OBJECTIVE: This study aimed to compare the subjective and geographic information system (GIS) assessments of the momentary food environment to explore the feasibility of using GIS data to predict eating behavior and inform geofenced interventions. METHODS: In total, 72 participants recorded their food intake in real-time for 14 days using an ecological momentary assessment approach. Participants logged their food intake and responded to approximately 5 randomly timed assessments each day. During each assessment, the participants reported the number and type of food outlets nearby. Their electronic diaries simultaneously recorded their GPS coordinates. The GPS data were later overlaid with a GIS map of food outlets to produce an objective count of the number of food outlets within 50 m of the participant. RESULTS: Correlations between self-reported and GIS counts of food outlets within 50 m were only of a small size (r=0.17; P<.001). Logistic regression analyses revealed that the GIS count significantly predicted eating similar to the self-reported counts (area under the curve for the receiver operating characteristic curve [AUC-ROC] self-report=0.53, SE 0.00 versus AUC-ROC 50 m GIS=0.53, SE 0.00; P=.41). However, there was a significant difference between the GIS-derived and self-reported counts of food outlets and the self-reported type of food outlets (AUC-ROC self-reported outlet type=0.56, SE 0.01; P<.001). CONCLUSIONS: The subjective food environment appears to predict eating better than objectively measured food environments via GIS. mHealth apps may need to consider the type of food outlets rather than the raw number of outlets in an individual's environment.

Body Mass Index and stimulus control: Results from a real-world study of eating behaviour.

BACKGROUND: Evidence suggests decisions about when, what, and how much to eat can be influenced by external (location, food outlet presence, food availability) and internal (affect) cues. Although the relationship between stimulus control and obesity is debated, it is suggested that individuals with higher BMIs are more driven by cues to eating than individuals in the healthy-weight range (HWR). This study investigates the influence of stimulus control on real-world food intake, and whether stimulus control differs by BMI. It was hypothesised that, compared to those in the HWR, eating among individuals with higher BMIs would be under greater stimulus control. METHOD: 74 participants (n = 34 BMI < 24.9, n = 40 BMI > 24.9) recorded food intake for 14 days using Ecological Momentary Assessment. Participants also responded to 4-5 randomly-timed assessments per day. Known external and internal eating cues were assessed during both assessment types. Within-person logistic regression analyses were used to predict eating vs. non-eating occasions from stimulus control domains. FINDINGS: Results support the hypothesis that eating was influenced by stimulus control: food availability, affect, time of day, and location significantly distinguished between eating and non-eating instances (AUC-ROC = 0.56-0.69, all p's < 0.001). The presence of food outlets was significantly better at distinguishing between eating and non-eating instances for those with higher BMIs (compared to individuals in the HWR). DISCUSSION: Results support the notion of stimulus control in shaping eating decisions. Differences in levels of stimulus control between participants in the HWR compared to those with a high BMI suggest that dietary improvement interventions may be more effective when they are tailored to the individual and consider environmental influences on eating behaviour.

Inter-goal conflict and facilitation as predictors of adherence to dieting goals: an ecological momentary assessment study.

Objectives: To examine dieting goals within a system of individual goals, and the patterns by personally-relevant goals might interfere or facilitate each other.Design: 94 dieters completed an assessment of goals using Little's personal project analysis. Participants identified 7 goals; one of which was pre-defined as adhering to diet. Over the beginning 14 days of their diet, participants completed an Ecological Momentary Assessment study recording their food intake in real-time. Every evening, participants reported their goal engagement and which goals conflicted or facilitated with each other.Main outcome measures/results: Over the study duration, 1452 days of food intake and goal conflict/facilitation were recorded. Participants completed an average of 1.54 (SD = 0.85) snacks, an average of 0.94 (SD = 1.81) goal conflicts, and 4.16 (SD = 4.70) goal facilitations per day. Inter-goal conflict was associated with a significant but small improvement on individuals' mood, but was not associated with daily dietary intake or long-term weight-loss. Similarly, inter-goal facilitation was not associated with daily dietary intake or long-term weight-loss. Daily food intake was a significant predictor of long-term weight-loss.Conclusions: The results of this study suggest the impact of inter-goal conflict and facilitation on dieting is not via overall snack or food consumption.

Personal and situational predictors of everyday snacking: An application of temporal self-regulation theory.

OBJECTIVES: This study aims at testing predictions derived from temporal self-regulation theory (TST) in relation to discretionary food choices (snacks). TST combines a motivational sphere of influence (cognitions and temporal valuations resulting in intentions) with a momentary sphere (encompassing social and physical environmental cues). This dual approach differs from current health behaviour theories, but can potentially improve our understanding of the interplay of personal and environmental factors in health behaviour self-regulation. DESIGN: A mixed event-based and time-based (Ecological Momentary Assessment) study in 61 adults aged between 18 and 64, with a BMI range between 18.34 and 39.78 (M = 25.66, SD = 4.82) over two weeks. METHODS: Participants recorded their food and drink intake for two weeks in real time using electronic diaries. Participants also responded to non-consumption assessments at random intervals throughout each day. Momentary cues (individual, situational, and environmental factors) were assessed both during food logs and non-consumption assessments. Motivational factors, past behaviour, and trait self-regulation were assessed during baseline. RESULTS: Multilevel logistic regression analyses showed that across all snack types, environmental cues and negative affect were associated with an increased likelihood of snacking. Perceiving a cost of healthy eating to occur before eating was associated with an increased likelihood of snacking, whereas intentions and self-regulation were not. CONCLUSIONS: Discretionary food intake is largely guided by momentary cues, and motivational-level factors, such as intention and self-regulation, are less important in the initiation of discretionary food intake. Statement of contribution What is already known on this subject? Overweight and obesity are a result of prolonged periods of energy imbalance between energy intake and expenditure (Hill & Peters, ). One of the key behavioural determinants of energy imbalances results from food intake, specifically from discretionary food choices (snacking). Temporal self-regulation theory (Hall & Fong, ) takes into account both deliberate and momentary influences on health behaviour, which is especially relevant to exploring the drivers of snacking. What does this study add? Offers new insight into the application of TST in explaining momentary eating behaviours. Snacking initiation is guided by momentary cues, not person-level factors. Dietary interventions should acknowledge the momentary cues that are associated with snacking.

Situational cues and momentary food environment predict everyday eating behavior in adults with overweight and obesity.

OBJECTIVES: Individual eating behavior is a risk factor for obesity and highly dependent on internal and external cues. Many studies also suggest that the food environment (i.e., food outlets) influences eating behavior. This study therefore examines the momentary food environment (at the time of eating) and the role of cues simultaneously in predicting everyday eating behavior in adults with overweight and obesity. METHOD: Intensive longitudinal study using ecological momentary assessment (EMA) over 14 days in 51 adults with overweight and obesity (average body mass index = 30.77; SD = 4.85) with a total of 745 participant days of data. Multiple daily assessments of eating (meals, high- or low-energy snacks) and randomly timed assessments. Cues and the momentary food environment were assessed during both assessment types. RESULTS: Random effects multinomial logistic regression shows that both internal (affect) and external (food availability, social situation, observing others eat) cues were associated with increased likelihood of eating. The momentary food environment predicted meals and snacking on top of cues, with a higher likelihood of high-energy snacks when fast food restaurants were close by (odds ratio [OR] = 1.89, 95% confidence interval [CI] = 1.22, 2.93) and a higher likelihood of low-energy snacks in proximity to supermarkets (OR = 2.29, 95% CI = 1.38, 3.82). CONCLUSIONS: Real-time eating behavior, both in terms of main meals and snacks, is associated with internal and external cues in adults with overweight and obesity. In addition, perceptions of the momentary food environment influence eating choices, emphasizing the importance of an integrated perspective on eating behavior and obesity prevention. (PsycINFO Database Record