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Proximity and Visibility of Fruits and Vegetables Influence Intake in a Kitchen Setting Among College Students

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Abstract

The hypothesis that participants will eat more fruits (apple slices) and vegetables (carrot cuts) if they are made more proximate and visible was tested using a 2 × 2 between-participants design. Proximity was manipulated by placing fruits and vegetables in a bowl at a table where participants sat (near) or 2 m from the table (far). Visibility was manipulated by placing fruits and vegetables in an opaque bowl that was covered (not visible) or in a clear bowl that was open (visible). The results showed that placing apple slices and carrot cuts in closer proximity to participants increased intake of these healthy foods. Making these foods more visible increased intake of apple slices but not carrot cuts, possibly because fruits taste sweet and so may be more motivationally salient than bitter-tasting carrots. Regardless, these data are the first to demonstrate experimentally that the proximity and visibility of fruits and vegetables can influence intake of these foods.

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... This "proximity effect" does not seem to be moderated by cognitive resource (Hunter et al., 2018). Similarly, placing a single healthier food closer increases the likelihood that it is consumed (Musher-Eizenman et al., 2010;Privitera & Creary, 2013). In real-world environments, such as cafeterias, people are more likely to select healthier and less healthy foods when they are placed on the front row in a servery compared to middle or back rows (Meyers & Stunkard, 1980;Rozin et al., 2011) and to purchase less chocolate when it is placed at a more distant till compared to closer, more convenient tills (Meiselman, Hedderley, Staddon, Pierson, & Symonds, 1994). ...
... However, the current evidence base is limited in a number of important ways making it uncertain whether and how such interventions might be implemented to improve diets at population level. First, most experimental studies of food proximity involve manipulating the distance of a single food (Maas et al., 2012;Musher-Eizenman et al., 2010;Painter et al., 2002;Privitera & Creary, 2013;Wansink et al., 2006), although any intervention capitalising on these effects would likely be implemented in a food environment in which multiple foods varying in healthiness are available. Only a small number of studies have examined the impact on consumption of experimentally varying the proximity of both healthier and less healthy foods (Kroese, Marchiori, & de Ridder, 2015;Meiselman et al., 1994;Meyers & Stunkard, 1980;Privitera & Zuraikat, 2014;Rozin et al., 2011), and these studies have generated inconsistent and incomplete findings. ...
... Few studies investigate the proximity effect with general population samples including participants with lower cognitive resource. Existing studies assessing the proximity effect often recruit university students or staff (Maas et al., 2012;Meiselman et al., 1994;Painter et al., 2002;Privitera & Creary, 2013;Privitera & Zuraikat, 2014;Wansink et al., 2006), being unrepresentative of the general population in having higher cognitive, material and social resources. Only two studies to date purposefully recruited those likely to have lower cognitive resource and directly investigated the role of cognitive resource on the proximity effect (Hunter et al., 2018). ...
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Background Placing food further away from people decreases likelihood of consumption (“Proximity Effect”). However, it is unclear how proximity affects consumption when both healthier and less healthy foods are available and cognitive resource for self-control is limited. Aims To test the hypothesis that when both healthier (raisins) and less healthy (chocolate M&Ms) foods are available, placing less healthy food far, rather than near, increases the likelihood that healthier food is consumed. Methods General population participants (N = 248) were all put under cognitive load and randomised to one of four groups: 1. Raisins near (20 cm), M&Ms far (70 cm); 2. Both foods near; 3. M&Ms near, raisins far; 4. Both far. Primary outcome: proportions of participants consuming raisins and M&Ms, respectively. Results The results did not support the primary hypothesis: when healthier and less healthy foods were both available, placing M&Ms far, rather than near, did not increase likelihood of consuming raisins (OR = 1.54, p = .432). Regardless of the M&Ms proximity, likelihood of consuming raisins was unaffected by the raisins’ proximity (62.9%(near) vs. 56.5%(far) OR = 0.61, p = .211). Likelihood of consuming M&Ms non-significantly decreased when they were far and raisins were near, and when both foods were far (OR = 2.83, p = .057). Likelihood of consuming M&Ms was affected by M&Ms proximity, being higher when near (68.3%) than far (55.6%), OR = 0.39, p = .015. Indices of cognitive load impact (higher vs lower) were unrelated to consumption of either food. Conclusions Likelihood of consuming a healthier food was unaffected by its proximity and that of a less healthy food. By contrast, likelihood of consuming a less healthy food was influenced by its proximity and possibly by that of a healthier food. These effects need replication in studies designed to detect smaller effect sizes. Trial registration This study was registered online with ISRCTN (ISRCTN11740813).
... The effect can be defined as the difference in selection or consumption of items based on the physical distance from the individual, with closer items being chosen and consumed more frequently than those located further away. Previous research has shown a difference in consumption between chocolate snacks located at 20cm and 70cm (Hunter, Hollands, Couturier, & Marteau, 2018;Maas, de Ridder, de Vet, & de Wit, 2012), with other research finding the effect between snack presented at 30cm and 200cm (Privitera & Creary, 2013;Privitera & Zuraikat, 2014). ...
... Past research has measured consumption in two ways: likelihood of consumption, and actual consumption. Both measures provide valuable insight into behaviour, with studies measuring actual consumption (Langlet, Fagerberg, Glossner, & Ioakimidis, 2017;Meiselman, Hedderley, Staddon, Pierson, & Symonds, 1994;Meyers & Stunkard, 1980;Privitera & Creary, 2013;Privitera & Zuraikat, 2014) exploring how the total consumption can be influenced though manipulating proximity, and studies measuring the likelihood of consumption (Baskin et al., 2016;Hunter et al., 2018;Maas et al., 2012) exploring how likely an individual is to consume any snacks. As previous studies have found varied results based on which outcome has been used, it is useful for the present study to examine both measures. ...
... Hunter et al., (2018) recently used a general population sample for their proximity effect study, suggesting that the proximity effect may be less prominent in the general population than a student sample, while also concluding that cognitive resources are unlikely to influence the proximity effect. Previous studies have used a university student sample (Maas et al., 2012;Privitera & Creary, 2013;Privitera & Zuraikat, 2014), and so the use of a student sample in the present study can be seen as following regular practice within the area. Finally, previous proximity effect studies have measured perceived effort with self-report questionnaire items (Knowles et al., 2017;Maas et al., 2012;Wansink, Painter, & Lee, 2006), but the present study will be the first to directly manipulate physical effort within a proximity effect environment, and should allow a more complete examination of the underpinning role of effort on the proximity effect. ...
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Obesity prevalence is increasing around the globe, with interventions manipulating the decision environment thought to have a large potential to change behaviour. One such simple yet effective intervention utilises the Proximity Effect, whereby snack consumption is decreased as the physical distance (proximity) between the individual and the snack is increased. Recent studies have suggested that visual salience and physical effort may underpin the effect. The current protocol outlines the first study to experimentally manipulate effort to determine its potential role in the proximity effect. A sample of 90 university students will be randomly allocated to one of four conditions in a 2 (proximity; 20cm vs 70cm) x 2 (effort; unwrapped vs wrapped) between subjects study. Twenty chocolate brownies will be presented at either 20cm or 70cm, with these brownies being either unwrapped or wrapped in a single layer of clear plastic film (high effort). Participants will also complete self-report measures for potential moderating factors including eating behaviour and perceived visual salience. Primary outcomes of the study are likelihood of consumption (whether an individual consumed any of the snack), and the actual amount consumed (kCal) according to experimental conditions. Implications of the results may be implemented in food service areas to decrease consumption of unhealthy foods by increasing the physical effort required to attain such foods.
... Choice architecture interventions to change health behaviour in micro-environments involve altering the properties and placement of objects or stimuli, such as food products [6]. One way in which the environment can be manipulated to change behaviour is through altering the proximity of food products; individuals consistently select and consume more of a food that is within easy reach compared to when it is placed further away [7][8][9][10][11][12][13][14][15][16][17]. This 'proximity effect' remains consistent across many environments, such as in cafeterias [10][11][12]17], shops [13], offices [7,9] and kitchens [14,15] and occurs regardless of food characteristics such as calorie content [11,14] see Table 1 in Additional file 1 for details of these studies. ...
... One way in which the environment can be manipulated to change behaviour is through altering the proximity of food products; individuals consistently select and consume more of a food that is within easy reach compared to when it is placed further away [7][8][9][10][11][12][13][14][15][16][17]. This 'proximity effect' remains consistent across many environments, such as in cafeterias [10][11][12]17], shops [13], offices [7,9] and kitchens [14,15] and occurs regardless of food characteristics such as calorie content [11,14] see Table 1 in Additional file 1 for details of these studies. Furthermore, this effect does not appear to differ by BMI, levels of craving, food preferences or body-weight [8,14,16]. ...
... Previous experimental studies investigating proximity are also often limited by small sample sizes, reducing the reliability of the results. Studies have tested as few as 12 or 17 participants in each condition [8,14,15], or 16 participants in total [9]see Table 1 in the Additional file 1 for sample sizes in these studies. The aforementioned studies do not report sample size calculations to justify using these sample sizes. ...
... Choice architecture interventions to change health behaviour in micro-environments involve altering the properties and placement of objects or stimuli, such as food products [6]. One way in which the environment can be manipulated to change behaviour is through altering the proximity of food products; individuals consistently select and consume more of a food that is within easy reach compared to when it is placed further away [7][8][9][10][11][12][13][14][15][16][17]. This 'proximity effect' remains consistent across many environments, such as in cafeterias [10][11][12]17], shops [13], offices [7,9] and kitchens [14,15] and occurs regardless of food characteristics such as calorie content [11,14] see Table 1 in Additional file 1 for details of these studies. ...
... One way in which the environment can be manipulated to change behaviour is through altering the proximity of food products; individuals consistently select and consume more of a food that is within easy reach compared to when it is placed further away [7][8][9][10][11][12][13][14][15][16][17]. This 'proximity effect' remains consistent across many environments, such as in cafeterias [10][11][12]17], shops [13], offices [7,9] and kitchens [14,15] and occurs regardless of food characteristics such as calorie content [11,14] see Table 1 in Additional file 1 for details of these studies. Furthermore, this effect does not appear to differ by BMI, levels of craving, food preferences or body-weight [8,14,16]. ...
... Previous experimental studies investigating proximity are also often limited by small sample sizes, reducing the reliability of the results. Studies have tested as few as 12 or 17 participants in each condition [8,14,15], or 16 participants in total [9]see Table 1 in the Additional file 1 for sample sizes in these studies. The aforementioned studies do not report sample size calculations to justify using these sample sizes. ...
Article
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Background: Despite attempts to improve diet at population level, people living in material and social deprivation continue to consume unhealthy diets. Executive function - the ability to regulate behaviour and resist impulses - is weaker in individuals living in deprivation. Dietary interventions that educate and persuade people to reflect on and actively change behaviour may therefore disproportionately benefit individuals who are socioeconomically advantaged and have stronger executive function, thus exacerbating inequalities in health resulting from unhealthy diets. In contrast, manipulating environmental cues, such as how far away a food is placed, does not appeal to reasoned action and is thought to operate largely outside of awareness to influence behaviour. People eat more of a food when it is placed closer to them, an effect seemingly robust to context, food quality and body-weight status. However, previous studies of this 'proximity effect' are limited by small samples consisting mainly of university staff or students, biased towards higher socio-economic position and therefore likely stronger executive function. This study aims to test the hypothesis that placing food further away from a person decreases intake of that food regardless of executive function. Methods/design: 156 members of the general public, recruited from low and high socio-economic groups, will be randomised to one of two conditions varying in the proximity of a snack food relative to their position: 20 cm or 70 cm. Participants are told they will be taking part in a relaxation study - and are fully debriefed at the conclusion of the session. The primary outcome is the proportion of participants eating any amount of snack food and the secondary outcome is the mean amount eaten. Executive function is assessed using the Stroop task. Discussion: The proposed study takes a novel step by investigating the effect of proximity on snack food intake in a general population sample consisting of those with high and low executive function, appropriately powered to detect the predicted proximity effect. If this effect occurs irrespective of executive function and socio-economic position, it may have potential to reduce inequalities patterned by socio-economic position if implemented in real-world settings such as shops or restaurants. Trial registration: Registered with the ISRCTN registry: ISRCTN46995850 on 07 October 2015.
... Studies on the visibility and proximity of foods show that participants eat more of candies (M&Ms) if they are visible, even when these candies are not proximate, i.e., 2 m from the participant [21,22]. Similar effects of visibility are observed with sweet-tasting fruits (apples), but not bitter-tasting vegetables (carrots) [23]. Privitera et al. [23] suggest that the effect of visibility on fruit, but not vegetable intake, may be specifically related to perceived tastes, with foods perceived as tasting sweeter reported as more visually appealing, wanted, or motivationally salient than foods perceived as tasting less sweet, regardless of the actual number of calories. ...
... Similar effects of visibility are observed with sweet-tasting fruits (apples), but not bitter-tasting vegetables (carrots) [23]. Privitera et al. [23] suggest that the effect of visibility on fruit, but not vegetable intake, may be specifically related to perceived tastes, with foods perceived as tasting sweeter reported as more visually appealing, wanted, or motivationally salient than foods perceived as tasting less sweet, regardless of the actual number of calories. ...
... Because motivational salience is directly related to the arousal of a stimulus or food cue [27,28], it was hypothesized that arousal may be significantly enhanced following the presentation of more desirable foods, i.e., foods that induced greater motivational salience or wanting [23,29]. While significant changes in arousal were observed following the presentation of high fat and high sugar foods, these changes were fully accounted for by a participant's dietary history with sugar and fat intake. ...
Article
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Background: While brain imaging studies show that reward regions in the human brain that regulate reward-guided behavior and integrate sensory modalities of smell, taste, and texture respond preferentially to high calorie foods, few studies account for dietary histories or account for recent behavioral evidence showing preferential responding for fruits (a low calorie food that tastes sweet). To address these concerns, the present study tested the hypothesis that images of high/low fat and sugar foods, even sugary foods that are low calorie (i.e., fruits), will enhance emotional responsiveness and that these changes may be related to dietary histories with fat and sugar intake. Method: Participants were shown 4 sets of 15 food images with each food image automatically timed every 9 s to transition to a new food image; participant pre-post mood and arousal was measured. The 4 sets of food images were high fat-high sugar (HFHS; desserts), high fat-low sugar (HFLS; fried foods), low fat-high sugar (LFHS; fruits), or low fat-low sugar (LFLS; vegetables) foods. To account for dietary histories, participants also completed estimated daily intake scales (EDIS) for sugar and fat. Results: Mood and arousal significantly increased in all groups, except Group LFLS, and even in a group that was low calorie but shown foods that taste sweet, i.e., Group LFHS. Interestingly, changes in arousal, but not mood, were dependent on participant histories with sugar and fat intake. Conclusion: Changes in emotional responsiveness to food images were nutrient-specific, which can be a more detailed level of analysis for assessing responsiveness to food images. Also, participant histories with sugar and fat should be taken into account as these histories can explain the changes in arousal observed here.
... For studies that isolate a single food, most studies that manipulated the proximity of food in a microscale food environment have used ''junk'' foods, such as candies (Painter, Wansink, & Hieggelke, 2002;Wansink et al., 2006). In a pair of experiments, a more recent investigation showed for the first time that placing apple slices (fruit) or carrot sticks (vegetable) closer to a participant, increased intake of those healthier foods in a microscale food environment (Privitera & Creary, 2013). This more recent investigation established a potential way in which a food environment can be structured to increase intake of fruits and vegetables. ...
... One limitation of studies that have investigated how the proximity of foods in an environment influences intake is that only one food was made available to a participant at a given time (Painter et al., 2002;Privitera & Creary, 2013;Wansink et al., 2006). For studies with candies, fruits, or vegetables, only that one food type was available to eat at the time of the proximity manipulation. ...
... The kitchen area was located along the east wall and consisted of a faucet, sink, counter (2 m length  0.6 m width  1 m height), four cabinets, and a refrigerator. As shown in previous analyses in this kitchen setting (e.g., Privitera & Creary, 2013) participants reported that this setting looks (mundane realism) and feels (experimental realism) like a real kitchen. This kitchen setting is a space that is used for the purposes of preparing and eating foods only and is a designated eating area. ...
Article
The objective of this study was to test if proximity of a food or preference for a food influences food intake in a competitive food environment in which one low calorie/low fat (apple slices) and one higher calorie/higher fat (buttered popcorn) food was available in the same environment. The proximity of popcorn and apple slices was manipulated and 56 participants were randomly assigned to groups. In Group Apples Near, apple slices were placed near (within arms reach) a participant and popcorn was placed far (2 m away). In Group Popcorn Near, buttered popcorn was placed near and apple slices were placed far. As a control for the absence of a proximity manipulation, Group Both Near had both test foods placed near. Although participants rated the popcorn as more liked than apples, the food that was placed closer to the participant was consumed most in the two experimental groups, regardless of preference (R(2) = 0.38). Total energy intake was reduced most when popcorn was placed far from a participant compared to when it was placed near (R(2) = 0.24). The effects reported here were not moderated by BMI and did not vary by sex. In all, the results support the hypothesis that making a low calorie food more proximate will reduce total energy intake and increase intake of a low calorie food, even when a higher calorie and more preferred food is also available, but less proximate.
... Current evidence for whether the proximity effect is moderated by cognitive resource is limited. First, sample populations are not representative of general populations, with most studies recruiting primarily university staff and students (Maas et al., 2012;Meiselman, Hedderley, Staddon, Pierson, & Symonds, 1994;Painter, Wansink, & Hieggelke, 2002;Privitera & Creary, 2013;Privitera & Zuraikat, 2014;Rozin et al., 2011;Wansink, Painter, & Lee, 2006). These populations have higher education levels, indicating higher SEP, and thus likely have higher levels of cognitive resource. ...
... Second, the quality of existing studies is compromised by small sample sizes and absence of power calculations (e.g. Maas et al., 2012;Painter et al., 2002;Privitera & Creary, 2013;Privitera & Zuraikat, 2014;Wansink et al., 2006) which limit the reproducibility of the effects found in many studies (Munaf o et al., 2017;Button et al., 2013). Studies recruiting larger samples in general populations will provide more reliable and generaliseable estimates of the magnitude of the proximity effect (Bucher et al., 2016). ...
Article
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Objective: Placing snack-food further away from people consistently decreases its consumption (“proximity effect”). However, given diet-related health inequalities, it is important to know whether interventions that alter food proximity have potential to change behaviour regardless of cognitive resource (capacity for self-control). This is often lower in those in lower socio-economic positions, who also tend to have less healthy diet-related behaviours. Study 1 aims to replicate the proximity effect in a general population sample and estimate whether trait-level cognitive resource moderates the effect. In a stronger test, Study 2 investigates whether the effect is similar regardless of manipulated state-level cognitive resource. Method: Participants were recruited into two laboratory studies (Study 1: n=159; Study 2: n=246). A bowl of an unhealthy snack was positioned near (20cm) or far (70cm) from the participant, as randomised. In Study 2, participants were further randomised to a cognitive load intervention. The pre-specified primary outcome was the proportion of participants taking any of the snack. Results: Significantly fewer participants took the snack when far compared with near in Study 2 (57.7% vs 70.7%, β = -1.63, p=.020), but not in Study 1 (53.8% vs 63.3%, X2=1.12, p=.289). Removing participants who moved the bowl (i.e. who did not adhere to protocol), increased the effect-sizes: Study 1: 39.3% vs 63.9%, X2=6.43, p=.011; Study 2: 56.0% vs 73.9%, β =-2.46, p=.003. Effects were not moderated by cognitive resource. Conclusions: These studies provide the most robust evidence to date that placing food further away reduces likelihood of consumption in general population samples, an effect unlikely to be moderated by cognitive resource. This indicates potential for interventions altering food proximity to contribute to addressing health inequalities, but requires testing in real-world settings.
... Current evidence for whether the proximity effect is moderated by cognitive resource is limited. First, sample populations are not representative of general populations, with most studies recruiting primarily university staff and students (Maas et al., 2012;Meiselman, Hedderley, Staddon, Pierson, & Symonds, 1994;Painter, Wansink, & Hieggelke, 2002;Privitera & Creary, 2013;Privitera & Zuraikat, 2014;Rozin et al., 2011;Wansink, Painter, & Lee, 2006). These populations have higher education levels, indicating higher SEP, and thus likely have higher levels of cognitive resource. ...
... Second, the quality of existing studies is compromised by small sample sizes and absence of power calculations (e.g. Maas et al., 2012;Painter et al., 2002;Privitera & Creary, 2013;Privitera & Zuraikat, 2014;Wansink et al., 2006) which limit the reproducibility of the effects found in many studies (Munaf o et al., 2017;Button et al., 2013). Studies recruiting larger samples in general populations will provide more reliable and generaliseable estimates of the magnitude of the proximity effect (Bucher et al., 2016). ...
Article
Full-text available
Objective: Placing snack-food further away from people consistently decreases its consumption ("proximity effect"). However, given diet-related health inequalities, it is important to know whether interventions that alter food proximity have potential to change behaviour regardless of cognitive resource (capacity for self-control). This is often lower in those in lower socio-economic positions, who also tend to have less healthy diet-related behaviours. Study 1 aims to replicate the proximity effect in a general population sample and estimate whether trait-level cognitive resource moderates the effect. In a stronger test, Study 2 investigates whether the effect is similar regardless of manipulated state-level cognitive resource. Method: Participants were recruited into two laboratory studies (Study 1: n = 159; Study 2: n = 246). A bowl of an unhealthy snack was positioned near (20 cm) or far (70 cm) from the participant, as randomised. In Study 2, participants were further randomised to a cognitive load intervention. The pre-specified primary outcome was the proportion of participants taking any of the snack. Results: Significantly fewer participants took the snack when far compared with near in Study 2 (57.7% vs 70.7%, β = -1.63, p = 0.020), but not in Study 1 (53.8% vs 63.3%, X2 = 1.12, p = 0.289). Removing participants who moved the bowl (i.e. who did not adhere to protocol), increased the effect-sizes: Study 1: 39.3% vs 63.9%, X2 = 6.43, p = 0.011; Study 2: 56.0% vs 73.9%, β = -2.46, p = 0.003. Effects were not moderated by cognitive resource. Conclusions: These studies provide the most robust evidence to date that placing food further away reduces likelihood of consumption in general population samples, an effect unlikely to be moderated by cognitive resource. This indicates potential for interventions altering food proximity to contribute to addressing health inequalities, but requires testing in real-world settings. Trial registration: Both studies were registered with ISRCTN (Study 1 reference no.: ISRCTN46995850, Study 2 reference no.: ISRCTN14239872).
... Among clinical and nonclinical populations, evidence suggests that expressing emotion in art can significantly enhance mood [9,10], with many effects of enhanced mood attributed to the visual aesthetics of the images depicted [11]. Because the visual aesthetics of food can increase brain reward responses [12] food intake [13] and enhance emotion [14], it appears possible, but yet-to-be-tested, that expressions of foods in art can also serve to enhance mood. ...
... Behavioral data show similar patterns of over-responsiveness to images of "forbidden" foods, such as chocolates and other appetizing foods [24,25]. Visual images of sweet-tasting foods can also enhance consumption [13,26], ratings of deliciousness of foods [27], and positive emotion, even for healthy foods that taste sweet, i.e., fruits [14]. These findings suggest that without consuming food, men and women respond positively to the mere sight of many foods, which has implications for research on the effects of food on mood. ...
... (a) The choice percentage for the meat-heavy and vegetableforward meals and (b) the change in the choice percentages (of the meat-heavy meals) as a function of the change in the visual attractiveness (of the meat dishes), respectively. Note that * denotes p < 0.05 food choices as Privitera and Creary (2013) did, presumably as the distance difference was not that obvious in VR. ...
Article
In order to identify effective strategies to increase more environmentally friendly food choices, we conducted an experimental study to examine how the color contrast between the food and the background might influence people's choices between meat and vegetable dishes. Participants were instructed to choose three desirable dishes out of a choice set presented on a red‐ or green‐colored table in a simulated restaurant environment. Each choice set consisted of two meat and two vegetable dishes, so the participants had to choose between the meat‐heavy and vegetable‐forward meals. The participants chose the meat‐heavy meals more often than the chance level. However, the results revealed that using a red table to present the choice set could shift them toward choosing fewer meat‐heavy meals and thus more vegetable‐forward meals, and the visual attractiveness of the meat dishes was decreased when presented on the red tables. These findings provide empirical evidence regarding how the contrast between the color of food and the background color of the dining table can be used to modulate the sensory appeal of foods in order to promote sustainable food choices.
... Repeated exposure increased acceptance of fruit and vegetables (Barends, de Vries, Mojet, & de Graaf, 2013). Manipulating proximity and visibility increased intake of fruit and vegetables among college students (Privitera & Creary, 2013). ...
Article
Obesity is a growing public health problem and the increased prevalence calls for preventive measures. Choice architecture and dual brain process thinking has been suggested as a promising strategy. One of the behaviors that are of significant public health nutrition concern is the intake of sugar sweetened beverages (SSB’s) of young people. An intervention was developed for 4 canteens for students (age 16-23) of vocational schools. We slightly re-arranged the location of SSB’s in drink coolers by reducing visibility. The canteen managers collected data on sales volumes of beverages in combination over a period of 3 weeks and the data collection was supplemented with interviews and observations. The results showed that the intervention was able to reduce the purchasing of SSB in three of the four canteens. In one of the canteens where the cooler was behind the cafeteria desk there were little difference. It is assumed to be due to the fact that the students could not see the cooler while standing in line. The results suggests that rethinking of the canteen interior and physical food environment has the potential to affect purchasing of SSB.
... A healthy snack pack that was not previously offered was developed as the intervention component. The intervention was built on two types of choice dynamic principles: relocation and re-exposure 8,9 . Thus the intervention increased the accessibility of the healthy snack pack enhancing visibility of snack packs was increased and by re-expose the healthy option to customers more places in the cafeteria. ...
Article
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ABSTRACT Objectives: the aim of this study was to examine if influencing food choice dynamics by slightly altering the choice architecture by relocating and re-exposing the healthy option could increase sales of healthy snacks among young people in vocational school canteens. Materials and methods: a healthy eating intervention was developed for young people in canteens of 13 vocational schools. The subjects attending is mainly young men between 16 and 19 years of age. A healthy snack pack not previously offered was developed. The intervention targeted the access to healthy snacks using 2 environmental change strategies. Salience of the healthy snack pack was increased and customers were re-exposed to the healthy option more places. Sales data were collected pre/post test by canteen staff according to a protocol agreed with management canteens. Results: the results showed that significantly more students chose the healthy snacks when measured follow up after the intervention compared to baseline before. Sales of the unhealthy snacks did not change significantly. Conclusions: if students at vocational schools are to opt out unhealthy snacks and replace them with healthy alternatives, consideration should be given both to increase the exposure of healthy snacks and simultaneously undertake similar actions in the unhealthy snacks, for example by removing them or placing them less visibly in the canteen. Rethinking choice dynamics in self service food layouts through easy to implement minor changes seems to be able to change uptake of healthy options. More research is needed to explore effects and potentials of changing food choice architectures.
... There is growing recognition that both environmental nudges and cognitive factors can significantly affect what and how much people choose to eat. These factors include portion and package size (Scott, Nowlis, Mandel, & Morales, 2008), social influence (McFerran, Dahl, Fitzsimons, & Morales, 2010), food visibility (Privitera & Creary, 2013), traffic light color labels (Trudel, Murray, Kim, & Chen, 2015), nonfood incentives (Reimann, Bechara, & MacInnis, 2015;Reimann & Lane, 2017;Reimann, MacInnis, & Bechara, 2016), physical proximity (Baskin et al., 2016;Privitera & Zuraikat, 2014), attentional retraining (Kemps, Tiggemann, Orr, & Grear, 2014), food-related mental imagery (Christian, Miles, Kenyeri, Mattschey, & Macrae, 2016), and even the continuity people feel between their present and future selves (Rutchick, Slepian, Reyes, Pleskus, & Hershfield, 2018). Our research adds to this important line of work by showing that simple changes in the way food is presented can nudge individuals to make overall healthier choices and consume fewer calories. ...
Article
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Across 4 experiments, this research is the first to uncover the interaction effect of food type (indulgent vs. healthy) and food presentation order (first vs. last) on individuals' sequential food choices and their overall caloric intake. This work showed that, when selecting foods in a sequence (e.g., at a buffet or on a food ordering website), individuals are influenced by the first item they see and tend to make their subsequent food choices on the basis of this first item. This notion can be utilized to nudge individuals into consuming less food overall. In contrast to what one might intuitively assume, Experiment 1-a field study in a real-life cafeteria-showed that when an indulgent (healthy) dish is the first item, lower-calorie (higher-calorie) dishes are subsequently chosen and overall caloric consumption is lower (higher). Experiments 2 and 3 replicated these effects in the context of ordering food on a website. Experiment 4 further revealed that high (vs. low) cognitive load alters the identified interaction effect, such that when an indulgent dish is the first item, higher-calorie dishes are subsequently chosen.
... In particular, nonsensory factors were revealed to contribute significantly to the liking and acceptance of foods (Wadhera et al., 2014). These include food names (Cardello et al., 2012), proximity and visibility (Deng and Srinivasan, 2013;Kennedy-Hagan et al., 2011;Privitera and Creary, 2012;Wansink et al., 2006), varieties (Levitsky et al., 2012), portion sizes (Burger et al., 2011), colours (Koza et al., 2005) and shapes and surface areas (Van Ittersum and Wansink, 2011;Wada et al., 2007). ...
Article
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Picky eating with regard to fruit and vegetables is common among children. This study investigated the effectiveness of enhancing the visual appeal of fruit and vegetables to increase children’s liking and consumption of fruit and vegetables. A pre–post experimental design was used, and the control and experimental groups were repeatedly exposed to the original food and transformed food, respectively, over 6 weeks. Significant differences in the consumption of pumpkin, sweet potato, spinach, carrot and aubergine were observed between the groups, demonstrating that the appearance appeal of fruit and vegetables improves the willingness of children to try disliked fruit and vegetables and increases their vegetable consumption.
... The results, indeed, revealed that the intake of healthy foods increased. While, unhealthy foods are consumed less when they are distant (Maas et al., 2012;Privitera and Creary 2013). Studies have also focused on children and adolescents' perceptions of healthy food. ...
... Some studies have shown that nudging can influence food choices. Increased visibility, proximity and convenience of food items has been shown to increase selection [23], while decreased visibility, proximity and convenience reduced selection [24,25]. Nudges come in different forms [26], including salience nudges. ...
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Obesity is a major burden on healthcare systems. Simple, cost effective interventions that encourage healthier behaviours are required. The present study evaluated the efficacy of a salience nudge for promoting a change in milk selection from full-cream to low-fat (lower-calorie) in the kitchen of a university-based research institute that provided full-cream and low-fat milk free of charge. Milk selection was recorded for 12 weeks (baseline). A sign with the message “Pick me! I am low calorie” was then placed on the low-fat milk and selection was recorded for a further 12 weeks. During baseline, selection of low-fat milk was greater than selection of full-cream milk (p = 0.001) with no significant milk-type × time interaction (p = 0.12). During the intervention period overall milk selection was not different from baseline (p = 0.22), with low-fat milk selection remaining greater than full-cream milk selection (p < 0.001) and no significant milk-type × time interaction (p = 0.41). However, sub-analysis of the first two weeks of the intervention period indicated an increase in selection of both milk types (p = 0.03), but with a greater increase in low-fat milk selection (p = 0.01, milk-type × time interaction). However, milk selection then returned towards baseline during the rest of the intervention period. Thus, in the present setting, salience nudging promoted a transient increase in low-fat milk selection, but also increased selection of full-cream milk, indicating that nudging was not effective in promoting healthier milk choices.
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Background: Recent work has explored the effectiveness of the Proximity Effect, where increasing the physical distance between consumer and snacks reduces intake. Foods requiring less effort to attain, or being more visually appealing, are seen to be consumed more. Relatedly, perceived effort and visual salience are suggested mechanisms for the proximity effect, but no prior studies have directly manipulated these in association with the effect. Two between-subjects studies conducted in university laboratories are presented. Method: Twenty chocolate brownies that were either wrapped or unwrapped (Study 1, N = 85), or 250g of M&M's, either colourful or plain brown (Study 2, N = 80), were presented as effort and salience manipulations respectively to participants at either 20 cm or 70 cm. Consumption was measured as 'likelihood of consumption' (Yes/No) and 'actual consumption' (units/grams). Potential moderating variables including perceived effort and perceived visual salience were also measured. Results: Likelihood of consumption was positively predicted by perceived visual salience in both Studies, and by distance in Study 2. Significant main effects of distance, p < .001, ȵ2 = 0.102 (20 cm > 70 cm), effort, p < .001, ȵ2 = 0.089 (unwrapped > wrapped), and distance × effort interaction, p = .003, ȵ2 = 0.111, were observed in Study 1 for actual consumption. A main effect of distance was found in Study 2 for actual consumption, p < .001, ȵ2 = 0.062 (20 cm > 70 cm). Perceived visual salience positively correlated with actual consumption in both Studies. Conclusions: Increasing physical effort and placing snacks further away appear to act independently and interactively to reduce snack consumption. Manipulating snack colour does not appear to influence consumption, whereas perceptions of visual salience appear to influence consumption. As such, perceived visual salience and physical effort are thought to be key mechanisms underpinning the proximity effect. Pre-registration: Both Studies were pre-registered on the Open Science Framework (Study 1: 10.31234/osf.io/rmnys; Study 2: 10.31234/osf.io/u8bsz).
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Background: Overconsumption of food, alcohol, and tobacco products increases the risk of non-communicable diseases. Interventions to change characteristics of physical micro-environments where people may select or consume these products - including shops, restaurants, workplaces, and schools - are of considerable public health policy and research interest. This review addresses two types of intervention within such environments: altering the availability (the range and/or amount of options) of these products, or their proximity (the distance at which they are positioned) to potential consumers. Objectives: 1. To assess the impact on selection and consumption of altering the availability or proximity of (a) food (including non-alcoholic beverages), (b) alcohol, and (c) tobacco products.2. To assess the extent to which the impact of these interventions is modified by characteristics of: i. studies, ii. interventions, and iii. Participants: Search methods: We searched CENTRAL, MEDLINE, Embase, PsycINFO, and seven other published or grey literature databases, as well as trial registries and key websites, up to 23 July 2018, followed by citation searches. Selection criteria: We included randomised controlled trials with between-participants (parallel group) or within-participants (cross-over) designs. Eligible studies compared effects of exposure to at least two different levels of availability of a product or its proximity, and included a measure of selection or consumption of the manipulated product. Data collection and analysis: We used a novel semi-automated screening workflow and applied standard Cochrane methods to select eligible studies, collect data, and assess risk of bias. In separate analyses for availability interventions and proximity interventions, we combined results using random-effects meta-analysis and meta-regression models to estimate summary effect sizes (as standardised mean differences (SMDs)) and to investigate associations between summary effect sizes and selected study, intervention, or participant characteristics. We rated the certainty of evidence for each outcome using GRADE. Main results: We included 24 studies, with the majority (20/24) giving concerns about risk of bias. All of the included studies investigated food products; none investigated alcohol or tobacco. The majority were conducted in laboratory settings (14/24), with adult participants (17/24), and used between-participants designs (19/24). All studies were conducted in high-income countries, predominantly in the USA (14/24).Six studies investigated availability interventions, of which two changed the absolute number of different options available, and four altered the relative proportion of less-healthy (to healthier) options. Most studies (4/6) manipulated snack foods or drinks. For selection outcomes, meta-analysis of three comparisons from three studies (n = 154) found that exposure to fewer options resulted in a large reduction in selection of the targeted food(s): SMD -1.13 (95% confidence interval (CI) -1.90 to -0.37) (low certainty evidence). For consumption outcomes, meta-analysis of three comparisons from two studies (n = 150) found that exposure to fewer options resulted in a moderate reduction in consumption of those foods, but with considerable uncertainty: SMD -0.55 (95% CI -1.27 to 0.18) (low certainty evidence).Eighteen studies investigated proximity interventions. Most (14/18) changed the distance at which a snack food or drink was placed from the participants, whilst four studies changed the order of meal components encountered along a line. For selection outcomes, only one study with one comparison (n = 41) was identified, which found that food placed farther away resulted in a moderate reduction in its selection: SMD -0.65 (95% CI -1.29 to -0.01) (very low certainty evidence). For consumption outcomes, meta-analysis of 15 comparisons from 12 studies (n = 1098) found that exposure to food placed farther away resulted in a moderate reduction in its consumption: SMD -0.60 (95% CI -0.84 to -0.36) (low certainty evidence). Meta-regression analyses indicated that this effect was greater: the farther away the product was placed; when only the targeted product(s) was available; when participants were of low deprivation status; and when the study was at high risk of bias. Authors' conclusions: The current evidence suggests that changing the number of available food options or altering the positioning of foods could contribute to meaningful changes in behaviour, justifying policy actions to promote such changes within food environments. However, the certainty of this evidence as assessed by GRADE is low or very low. To enable more certain and generalisable conclusions about these potentially important effects, further research is warranted in real-world settings, intervening across a wider range of foods - as well as alcohol and tobacco products - and over sustained time periods.
Article
Background: Overconsumption of food, alcohol, and tobacco products increases the risk of non-communicable diseases. Interventions to change characteristics of physical micro-environments where people may select or consume these products - including shops, restaurants, workplaces, and schools - are of considerable public health policy and research interest. This review addresses two types of intervention within such environments: altering the availability (the range and/or amount of options) of these products, or their proximity (the distance at which they are positioned) to potential consumers. Objectives: 1. To assess the impact on selection and consumption of altering the availability or proximity of (a) food (including non-alcoholic beverages), (b) alcohol, and (c) tobacco products.2. To assess the extent to which the impact of these interventions is modified by characteristics of: i. studies, ii. interventions, and iii. Participants: Search methods: We searched CENTRAL, MEDLINE, Embase, PsycINFO, and seven other published or grey literature databases, as well as trial registries and key websites, up to 23 July 2018, followed by citation searches. Selection criteria: We included randomised controlled trials with between-participants (parallel group) or within-participants (cross-over) designs. Eligible studies compared effects of exposure to at least two different levels of availability of a product or its proximity, and included a measure of selection or consumption of the manipulated product. Data collection and analysis: We used a novel semi-automated screening workflow and applied standard Cochrane methods to select eligible studies, collect data, and assess risk of bias. In separate analyses for availability interventions and proximity interventions, we combined results using random-effects meta-analysis and meta-regression models to estimate summary effect sizes (as standardised mean differences (SMDs)) and to investigate associations between summary effect sizes and selected study, intervention, or participant characteristics. We rated the certainty of evidence for each outcome using GRADE. Main results: We included 24 studies, with the majority (20/24) giving concerns about risk of bias. All of the included studies investigated food products; none investigated alcohol or tobacco. The majority were conducted in laboratory settings (14/24), with adult participants (17/24), and used between-participants designs (19/24). All studies were conducted in high-income countries, predominantly in the USA (14/24).Six studies investigated availability interventions, of which two changed the absolute number of different options available, and four altered the relative proportion of less-healthy (to healthier) options. Most studies (4/6) manipulated snack foods or drinks. For selection outcomes, meta-analysis of three comparisons from three studies (n = 154) found that exposure to fewer options resulted in a large reduction in selection of the targeted food(s): SMD -1.13 (95% confidence interval (CI) -1.90 to -0.37) (low certainty evidence). For consumption outcomes, meta-analysis of three comparisons from two studies (n = 150) found that exposure to fewer options resulted in a moderate reduction in consumption of those foods, but with considerable uncertainty: SMD -0.55 (95% CI -1.27 to 0.18) (low certainty evidence).Eighteen studies investigated proximity interventions. Most (14/18) changed the distance at which a snack food or drink was placed from the participants, whilst four studies changed the order of meal components encountered along a line. For selection outcomes, only one study with one comparison (n = 41) was identified, which found that food placed farther away resulted in a moderate reduction in its selection: SMD -0.65 (95% CI -1.29 to -0.01) (very low certainty evidence). For consumption outcomes, meta-analysis of 15 comparisons from 12 studies (n = 1098) found that exposure to food placed farther away resulted in a moderate reduction in its consumption: SMD -0.60 (95% CI -0.84 to -0.36) (low certainty evidence). Meta-regression analyses indicated that this effect was greater: the farther away the product was placed; when only the targeted product(s) was available; when participants were of low deprivation status; and when the study was at high risk of bias. Authors' conclusions: The current evidence suggests that changing the number of available food options or altering the positioning of foods could contribute to meaningful changes in behaviour, justifying policy actions to promote such changes within food environments. However, the certainty of this evidence as assessed by GRADE is low or very low. To enable more certain and generalisable conclusions about these potentially important effects, further research is warranted in real-world settings, intervening across a wider range of foods - as well as alcohol and tobacco products - and over sustained time periods.
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Objective: One method of influencing an individual’s food consumption involves placing unhealthy snacks further away from individuals, known as the “proximity effect”. However, only one laboratory study has explored the effect while both an unhealthy and a healthy option are presented simultaneously, known as a competitive environment. Further, little is known about the potential underpinning mechanisms of the effect. The current study aims to replicate the proximity effect in a competitive environment, and to explore the role of visual salience and effort in the proximity effect. Method: Fifty-six participants were asked to complete a two-part questionnaire under the cover story of a relaxation study. Two bowls were presented to participants, each containing either 250g chocolate M&M’s or 250g mixed fruit pieces. Each bowl was positioned either 20cm or 70cm from the participant, creating four conditions. Consumption of each snack was compared between conditions. Results: No main effects were found. A significant interaction between snack type and chocolate position was found (p = .010, ȵ^2 = .159), with fruit consumption being significantly higher when chocolate was at located at 20cm compared to 70cm (53.35g vs 22.35g, p = .042). Higher visual salience of each snack type correlated to more of the snack being consumed, ps < .017. Results were similar when calories consumed were analysed. Conclusions: The main finding was that of an unconventional proximity effect where the consumption of a snack does not depend on its position, but rather the relative position of another snack. Implications of the study could inform café and supermarket layouts to exploit the interaction between moving healthy items closer in addition to moving unhealthy items further away, in order to maximise choice of healthy items.
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Context: Federal regulation mandates that the US National School Lunch Program nutrition standards align with the Dietary Guidelines for Americans. As students consume a substantial proportion of their nutrition during school lunch, increasing access to healthy foods is proposed to improve student dietary outcomes. The purpose of this review is to assess whether policy changes impacted food-consumption behaviors of students during periods when (1) school wellness policies were implemented (2006-2007); (2) the Healthy, Hunger-Free Kids Act was passed (2010-2012); and (3) the Healthy, Hunger-Free Kids Act was implemented (2012-present). PubMed, Web of Science, and Science Direct were searched for primary research studies. Policy evaluations and interventions implemented from 2006 to 2016 were included. A total of 31 studies evaluating plate waste, dietary intake, food selection, and/or purchasing patterns were identified and reviewed. Fourteen of 19 intervention and longitudinal observation studies reported improved food-consumption behaviors (increased selection, intake, and sales of healthy foods, and decreased plate waste). Only 2 of 12 one-time observation studies reported food-consumption behaviors meeting target nutrition standards. The majority of studies indicated that increasing access to healthy foods during school lunch improved students' dietary intakes. Challenges related to study design, adaptation period, quality of foods, and policy implementation likely affect a school lunch program's ability to impact students' food-consumption behaviors. Ongoing evaluation of these programs is warranted.
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Preschoolers do not consume whole fruit and vegetables (FVs) in recommended quantities. Two strategies to increase FV intake were tested. One Head Start preschool participated. Two variations of family-style feeding were compared to usual practice: (1) Fruits, vegetables, and milk were served before the main meal (first course); and (2) fruits, vegetables, and milk were served before the main meal and meats and grains were removed from the table after the first serving (combination). A within-subject crossover design was used to test each condition for three meals. The amount of food served and consumed was weighed and converted to Child and Adult Care Feeding Program (CACFP) standard serving sizes for analysis. Eighty-five children ages 3-5 participated. The sample was 81% Hispanic with diverse racial backgrounds. Thirty percent of the children were overweight. FV consumption was at CACFP recommended levels at baseline and remained consistent across conditions. The average amount served for each meal component was at or above CACFP recommendations for all foods except milk, which was consistently served in small portions. Meat and grains servings were frequently 2-3 times larger than CACFP recommendations. Milk consumption was significantly higher in the Combined intervention for two meals. Children ate significantly less meat during the Combined intervention for one meal. The intervention led to significant increases in milk consumption, which was the only underconsumed meal component. These strategies should be tested with children who have lower baseline intake of FVs.
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Two experiments were conducted to test a prediction of the arousal hypothesis that increased arousal will increase intake of less palatable and healthy foods. In both experiments, arousal was manipulated by adjusting the volume of a movie (soft, loud volume) while participants consumed foods. In Experiment 1, participants ate fresh (palatable) or stale (less palatable) popcorn during a 9-minute movie played at a soft or loud volume. Experiment 2 used the same procedures with healthier foods (carrot sticks and apple slices). Partial support for the arousal hypothesis in Experiment 1 showed that participants consumed more stale but not fresh popcorn in the loud (high arousal) versus soft (low arousal) volume group. These findings suggest that low but not high palatable foods are susceptible to manipulations of arousal. Consistent with this interpretation, Experiment 2 showed that high but not low environmental arousal increased intake of the fruits and vegetables, which are typically rated as lower in palatability compared to high fat foods. These results show that high arousal in an eating-typical environment increases intake of less palatable foods, and healthy foods (i.e., fruits and vegetables). Increasing the availability of healthier foods in a loud food environment can have a positive impact on increasing intake of fruits and vegetables in that environment.
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Rats learned to associate one flavor conditioned stimulus (CS; grape or orange) with an ethanol (caloric) or saccharin (sweet but noncaloric) solution unconditioned stimulus (US), and the other flavor CS with either the other US or plain tap water. They were then given two-bottle choice tests between the flavor CSs apart from the USs. Flavors associated with 5% ethanol were preferred over saccharin-paired and water-paired flavors by sated rats, and food deprivation during the choice test enhanced this preference. The ethanol-paired flavor preference was not affected by feeding conditions (deprived vs. ad lib) during CS-US conditioning. Flavors associated with 8% sucrose (caloric + sweet tasting) were preferred over water-paired flavors during ad lib testing, and this preference was also enhanced by food deprivation. Flavors associated with 0.028% or 0.25% saccharin were preferred over flavors paired with water; however, these preferences were not enhanced by deprivation at test time. In all cases, calorie-mediated preferences, at their highest levels, were stronger than taste-mediated preferences. These experiments indicate that preferences for flavors associated with caloric substances are positively related to hunger level at test time, but preferences mediated by a prior preferred taste are independent of test-time hunger level.
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Given the number of volume judgments made by consumers, for example, deciding which package is larger and by how much, it is surprising that little research pertaining to volume perceptions has been done in marketing. In this article, the authors examine the interplay of expectations based on perceptual inputs versus experiences based on sensory input in the context of volume perceptions. Specifically, they examine biases in the perception of volume due to container shape. The height of the container emerges as a vital dimension that consumers appear to use as a simplifying visual heuristic to make a volume judgment. However, perceived consumption, contrary to perceived volume, is related inversely to height. This lowered perceived consumption is hypothesized and shown to increase actual consumption. A series of seven laboratory experiments programmatically test model predictions. Results show that perceived volume, perceived consumption, and actual consumption are related sequentially. Furthermore, the authors show that container shape affects preference, choice, and postconsumption satisfaction. The authors discuss theoretical implications for contrast effects when expectancies are disconfirmed, specifically as they relate to biases in visual information processing, and provide managerial implications of the results for package design, communication, and pricing.
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Built environments at many scales influence the type and amount of food consumed. Macroscale food systems and food landscapes influence food choices, and microscale rooms, furniture, containers, and objects influence food intake. The authors review literature about how four ubiquitous microscale built environments are persistent but often unrecognized influences on food intake. Kitchenscapes influence food intake through availability, diversity, and visibility of foods; tablescapes through variety, abundance, and accessibility; platescapes through portion and/or package size, arrangement, and utensil type; and food-scapes through food-item forms and landmarks. Microgeographies of built environments provide a subtle, pervasive, and often unconscious influence on food choices, food intake, obesity, and health. Reengineering built environments may offer opportunities to shape food intake.
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Studies show inconsistent results with regards to whether eating slower can enhance satiety and reduce intake in a meal. Some methodological differences are apparent and could potentially explain why results are not consistent across studies. To determine whether eating slower can enhance satiety and reduce intake when rate of eating is manipulated and not manipulated in a kitchen setting using a sample of participants who exhibit high dietary restraint (HDR). Two samples of college students who exhibit HDR, which is a group likely to use behavioral strategies to manage intake, were selected in a prescreening session. Participants were told how fast or slow to eat (Variation 1) or allowed to eat at their own pace (Variation 2). Self-reported satiety during the meal and amount consumed was recorded. The types of foods, macronutrient intakes, weights of foods, order of food intakes, and the dimensions of foods were held constant between groups to control for group differences in the sensory and hedonic qualities of the meals. Eating slower enhanced mid-meal satiety ratings, but only when instructions were given to eat fast or slow (Variation 1). In both variations, eating slower did not reduce amount consumed in the meal, although each variation had sufficient power to detect differences. Eating slower is not likely to be an effective strategy to control intake in a meal among those exhibiting HDR.
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When people stockpile products, how do they decide when and how much they will consume? To answer this question, the authors develop a framework that shows how the salience and convenience of products influence postpurchase consumption incidence and quantity. Multiple research methods--including scanner data analysis, a field study, and two laboratory studies--show that stockpiling increases product salience and triggers consumption incidence among high-convenience products. However, when the decision is made to consume a product, stockpiling increases the consumption quantity for both high- and low-convenience products. In addition to providing new insights on how consumers make postpurchase consumption decisions, these results have implications for the debate on the value of promotions that induce stockpiling. [ABSTRACT FROM AUTHOR]
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We examined whether young adult meal patterning, dietary intake, and home food availability differed among nonstudents, 2-year college students, and 4-year college students (N = 1687; mean age = 20.5 years). Unadjusted analyses showed that few young adults consumed optimal diets and, compared with 4-year college students, nonstudents and 2-year students consumed fewer meals and poorer diets. After controlling for sociodemographics and living arrangements, we found that over half of the observed associations remained significant (P < .05). Nutrition interventions are needed for young adults, particularly specific at-risk groups.
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Two experiments were conducted to assess the effects of self-attention and public attention to food intake on eating by dieters and nondieters. Female dieters ate the greatest number of candies ad lib after consuming a forced two-milk shake preload; the addition of either self-attention or implied public attention, through the manipulated availability of a waste basket for the disposing of candy wrappers, inhibited eating substantially. For nondieters, the preload itself inhibited candy consumption, which declined further only under conditions of public attention to candy intake. In a second experiment, self- and public attention again inhibited the cookie consumption of preloaded dieters, but preloaded nondieters were not influenced by the attention manipulations, eating minimally in all conditions. Nondieters who were not preloaded, however, did reduce their intake in the two attention conditions. Implications for regulatory self-control were discussed.
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We examined trends in fruit and vegetable consumption in the United States. A 6-item food frequency questionnaire was used to assess consumption among 434 121 adults in 49 states and the District of Columbia who were sampled in random-digit-dialed telephone surveys administered in 1994, 1996, 1998, and 2000. Although the geometric mean frequency of fruit and vegetable consumption declined slightly, the proportion of respondents consuming fruits and vegetables 5 or more times per day did not change. With the exception of the group aged 18 to 24 years, which experienced a 3-percentage-point increase, little change was seen among sociodemographic subgroups. Frequency of fruit and vegetable consumption changed little from 1994 to 2000. If increases are to be achieved, additional efforts and new strategies will be needed.
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It is often believed that people overeat the foods they like. We investigated whether environmental cues such as packaging and container size are so powerful that they can increase our intake of foods that are less palatable. In a 2 x 2 between-subjects design, 158 moviegoers in Philadelphia (57.6% male; 28.7 years) were randomly given a medium (120 g) or a large (240 g) container of free popcorn that was either fresh or stale (14 days old). Following the movie, consumption measures were taken, along with measures of perceived taste. Moviegoers who were given fresh popcorn ate 45.3% more popcorn when it was given to them in large containers. This container-size influence is so powerful that even when the popcorn was disliked, people still ate 33.6% more popcorn when eating from a large container than from a medium-size container. Even when foods are not palatable, large packages and containers can lead to overeating. The silver lining of these findings may be that portion size can also be used to increase the consumption of less preferred healthful foods, such as raw vegetables.
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Objective and purpose: Although there is increasing interest in how environmental factors influence food intake, there are mixed results and misunderstandings of how proximity and visibility influence consumption volume and contribute to obesity. The objective of this paper is to examine two questions: first, how does the proximity and salience of a food influence consumption volume? Second, are proximate foods consumed more frequently because they are proximate, or are they consumed more frequently because people lose track of how much they eat? Research methods and procedures: The 4-week study involved the chocolate candy consumption of 40 adult secretaries. The study utilized a 2 x 2 within-subject design where candy proximity was crossed with visibility. Proximity was manipulated by placing the chocolates on the desk of the participant or 2 m from the desk. Visibility was manipulated by placing the chocolates in covered bowls that were either clear or opaque. Chocolates were replenished each evening, and placement conditions were rotated every Monday. Daily consumption was noted and follow-up questionnaires were distributed and analyzed. Results: There were main effects for both proximity and visibility. People ate an average of 2.2 more candies each day when they were visible, and 1.8 candies more when they were proximately placed on their desk vs 2 m away. It is important to note, however, that there was a significant tendency for participants to consistently underestimate their daily consumption of proximately placed candies (-0.9) and overestimate their daily consumption of less proximately placed candies (+0.5). Discussion: These results show that the proximity and visibility of a food can consistently increase an adult's consumption of it. In addition, these results suggest that people may be biased to overestimate the consumption of foods that are less proximate, and to underestimate those that are more proximate. Knowing about these deviation tendencies is important for those attempting effectively monitor their consumption of fat and sugar.
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Contemporary Western society has encouraged an obesogenic culture of eating amongst youth. Multiple factors may influence an adolescent's susceptibility to this eating culture, and thus act as a barrier to healthy eating. Given the increasing prevalence of obesity amongst adolescents, the need to reduce these barriers has become a necessity. Twelve focus group discussions of single-sex groups of boys or girls ranging from early to-mid adolescence (N=73) were employed to identify key perceptions of, and influences upon, healthy eating behaviour. Thematic analysis identified four key factors as barriers to healthy eating. These factors were: physical and psychological reinforcement of eating behaviour; perceptions of food and eating behaviour; perceptions of contradictory food-related social pressures; and perceptions of the concept of healthy eating itself. Overall, healthy eating as a goal in its own right is notably absent from the data and would appear to be elided by competing pressures to eat unhealthily and to lose weight. This insight should inform the development of future food-related communications to adolescents.
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Eating represents a choice among many alternative behaviors. The purpose of this review is to provide an overview of how food reinforcement and behavioral choice theory are related to eating and to show how this theoretical approach may help organize research on eating from molecular genetics through treatment and prevention of obesity. Special emphasis is placed on how food reinforcement and behavioral choice theory are relevant to understanding excess energy intake and obesity and how they provide a framework for examining factors that may influence eating and are outside of those that may regulate energy homeostasis. Methods to measure food reinforcement are reviewed, along with factors that influence the reinforcing value of eating. Contributions of neuroscience and genetics to the study of food reinforcement are illustrated by using the example of dopamine. Implications of food reinforcement for obesity and positive energy balance are explored, with suggestions for novel approaches to obesity treatment based on the synthesis of behavioral and pharmacological approaches to food reinforcement.
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Given the number of volume judgments made by consumers, for example, deciding which package is larger and by how much, it is surprising that little research pertaining to volume perceptions has been done in marketing. In this article, the authors examine the interplay of expectations based on perceptual inputs versus experiences based on sensory input in the context of volume perceptions. Specifically, they examine biases in the perception of volume due to container shape. The height of the container emerges as a vital dimension that consumers appear to use as a simplifying visual heuristic to make a volume judgment. However, perceived consumption, contrary to perceived volume, is related inversely to height. This lowered perceived consumption is hypothesized and shown to increase actual consumption. A series of seven laboratory experiments programmatically test model predictions. Results show that perceived volume, perceived consumption, and actual consumption are related sequentially. Furthermore, the authors show that container shape affects preference, choice, and postconsumption satisfaction. The authors discuss theoretical implications for contrast effects when expectancies are disconfirmed, specifically as they relate to biases in visual information processing, and provide managerial implications of the results for package design, communication, and pricing.
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Objective: To determine the validity of an existing National Cancer Institute 7-item fruit and vegetable food frequency questionnaire (FFQ) with college students and to assess fruit and vegetable consumption, knowledge, and attitudes in this population. Methods: A survey was completed by 109 students. In addition to the FFQ, the survey contained questions determining awareness of the 5 a Day program, knowledge of recommended fruit and vegetable intake, and barriers to consumption of fruits and vegetables. Diet records were also collected and compared to the FFQ. Results: The FFQ was not shown to be valid; only 20% of students were aware of recommended daily fruit and vegetable intake; and taste, cost, and accessibility were identified as barriers to consumption of fruits and vegetables. Mean daily intake of fruits and vegetables based on FFQ was 4.2 servings. Conclusion: A better tool may be needed to quickly assess fruit and vegetable consumption by college students, and more nutrition education on this topic is recommended.
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Environmental variables can enable or impede children concerning what foods they consume. Availability and accessibility of foods are potentially important environmental variables. Availability concerns whether the foods are present in the home or school, while accessibility concerns whether the foods are prepared, presented, and/or maintained in a form that enables or encourages children to eat them. We hypothesized that greater availability and accessibility would lead to more consumption. Baseline data from two school nutrition education projects were used to examine relationships between availability/accessibility and consumption of fruits and vegetables. In one study, children's consumption of fruits and vegetables (from seven day food records) was related to home availability and accessibility (as assessed by a parent telephone interview), after controlling for psychosocial characteristics. In the second study, children ate more fruits and vegetables for lunch at schools that offered more fruits and vegetables for lunch, after controlling for socioeconomic status. These results offer preliminary support for the hypothesized relationships. Future research must delineate the anticipated complex relationships among food purchase and preparation practices that lead to availability and accessibility, child and parent food preferences, and consumption, in order to more clearly guide interventions.
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In four experiments, food deprivation was varied during conditioning and testing of conditioning of flavor preferences by sweeteners. Conditioned preferences for a flavor associated with a more concentrated solution were enhanced by increased deprivation in training whether sucrose or saccharin was used when rats consumed solutions freely during training. When consumption of solutions was controlled and higher deprivation levels were used, preference for the higher concentration of sucrose was still enhanced by increased deprivation in training, but this did not occur with saccharin. We suggest that deprivation may enhance the reinforcing value of sweetness only when calories increase along with sweetness. We also suggest that deprivation can enhance flavor preference learning by increasing consumption and thereby increasing exposure to the flavored solutions.
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The simultaneous increases in obesity in almost all countries seem to be driven mainly by changes in the global food system, which is producing more processed, affordable, and effectively marketed food than ever before. This passive overconsumption of energy leading to obesity is a predictable outcome of market economies predicated on consumption-based growth. The global food system drivers interact with local environmental factors to create a wide variation in obesity prevalence between populations. Within populations, the interactions between environmental and individual factors, including genetic makeup, explain variability in body size between individuals. However, even with this individual variation, the epidemic has predictable patterns in subpopulations. In low-income countries, obesity mostly affects middle-aged adults (especially women) from wealthy, urban environments; whereas in high-income countries it affects both sexes and all ages, but is disproportionately greater in disadvantaged groups. Unlike other major causes of preventable death and disability, such as tobacco use, injuries, and infectious diseases, there are no exemplar populations in which the obesity epidemic has been reversed by public health measures. This absence increases the urgency for evidence-creating policy action, with a priority on reduction of the supply-side drivers.
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To examine the association between food sold in school vending machines and the dietary behaviors of students. The 2005-2006 U.S. Health Behavior in School-aged Children survey was administered to 6th to 10th graders and school administrators. Dietary intake in students was estimated with a brief food frequency measure. School administrators completed questions regarding food sold in vending machines. For each food intake behavior, a multilevel regression analysis modeled students (level 1) nested within schools (level 2), with the corresponding food sold in vending machines as the main predictor. Control variables included gender, grade, family affluence, and school poverty index. Analyses were conducted separately for 6th to 8th and 9th-10th grades. In all, 83% of the schools (152 schools; 5,930 students) had vending machines that primarily sold food of minimal nutritional values (soft drinks, chips, and sweets). In younger grades, availability of fruit and/or vegetables and chocolate and/or sweets was positively related to the corresponding food intake, with vending machine content and school poverty index providing an explanation for 70.6% of between-school variation in fruit and/or vegetable consumption and 71.7% in sweets consumption. Among the older grades, there was no significant effect of food available in vending machines on reported consumption of those food. Vending machines are widely available in public schools in the United States. In younger grades, school vending machines were either positively or negatively related to the diets of the students, depending on what was sold in them. Schools are in a powerful position to influence the diets of children; therefore, attention to the food sold at school is necessary to try to improve their diets.
Article
Rats learned to associate one flavor conditioned stimulus (CS; grape or orange) with an ethanol (caloric) or saccharin (sweet but noncaloric) solution unconditioned stimulus (US), and the other flavor CS with either the other US or plain tap water. They were then given two-bottle choice tests between the flavor CSs apart from the USs. Flavors associated with 5% ethanol were preferred over saccharin-paired and water-paired flavors by sated rats, and food deprivation during the choice test enhanced this preference. The ethanol-paired flavor preference was not affected by feeding conditions (deprived vs. ad lib) during CS-US conditioning. Flavors associated with 8% sucrose (caloric + sweet tasting) were preferred over water-paired flavors during ad lib testing, and this preferences was also enhanced by food deprivation. Flavors associated with 0.028% or 0.25% saccharin were preferred over flavors paired with water; however, these preferences were not enhanced by deprivation at test time. In all cases, calorie-mediated preferences, at their highest levels, were stronger than taste-mediated preferences. These experiments indicate that preferences for flavors associated with caloric substances are positively related to hunger level at test time, but preferences mediated by a prior preferred taste are independent of test-time hunger level.
Article
Two home observations of eating styles and food storage and food cues in eight obese and eight nonobese families were conducted. Obese and nonobese children and their respective obese and nonobese parents were observed at dinner time and assessed on several different eating behaviors. Observers also recorded foods visible in the home and foods found on the first shelves of the freezer, refrigerator, and the most frequently used cupboard. Results did not reveal a different eating style between obese and nonobese families, although obese daughters appeared to eat differently than nonobese daughters. There were also similarities and differences in eating behaviors between children and parents, independent of individuals' weight status. Caloric totals of food storage, visible foods, and calories consumed appeared to be higher in obese households at the first observation, although obese families reduced the quantity of visible foods, and food consumption at observation two. The validity of socially desirable behaviors collected from more than one observation period and implications of the variability of the target behaviors when assessing obese families' eating styles and food habits are discussed.
Article
The microstructure of eating behavior reflects physical properties of food. Responses of lean and obese subjects to these physical properties are similar. For example, eating smaller bite-sized food units reduces initial ingestion rate and mean and local ingestion rate for the entire meal, but does not affect total intake in either lean or obese women. On the other hand, analysis of the microstructure of eating behavior also suggests that obese subjects are less hungry and are more motivated by food preferences than lean subjects. For example, in meals of bite-sized food units, initial ingestion rate is less affected by deprivation and more affected by food preference in obese than lean women. In buffet meals with a variety of foods, obese men eat dessert earlier in the meal, and eat more dessert and other energy dense foods than lean men. The research reviewed here suggests that treatments for obesity should not focus on modifying bite size and ingestion rate and other microstructural variables, which are largely determined by the physical properties of food. Instead, treatment should focus on food selection and the stimulatory effects of palatability on intake.
Article
Addictive drugs act on brain reward systems, although the brain evolved to respond not to drugs but to natural rewards, such as food and sex. Appropriate responses to natural rewards were evolutionarily important for survival, reproduction, and fitness. In a quirk of evolutionary fate, humans discovered how to stimulate this system artificially with drugs. Many molecular features of neural systems instantiating reward, and of those systems affected by addictive drugs, are conserved across species from Drosophilae to rats to humans and include dopamine (DA), G-proteins, pro- tein kinases, amine transporters, and transcription factors such as cAMP response element-binding protein (CREB). A better un- derstanding of natural brain reward systems will therefore en- hance understanding of the neural causation of addiction. Reinforcers, drives, and incentive systems It is first helpful to consider how the field has moved conceptually in recent decades. Although emotions are unobservable, many objective expressions and behavioral, physiological, and neural responses to emotional stimuli have been selected by evolution. Studies of these objective responses in animals and humans pro- vide valuable windows into brain reward function. Early drive theories held that hunger and thirst states motivated behavior directly as aversive drive states and that reinforcers simply re- duced those states, strengthening preceding stimulus-response (S-R) habits or increasing the probability of operant response emission. Rewards are recognized now to act at least as impor- tantly as hedonic incentives, causing neural representations that elicit motivation and goal pursuit, rather than as mere habit reinforcers. Physiological drive states nevertheless play important roles in incentive motivation, but primarily by increasing the perceived hedonic and incentive value of the corresponding re- ward; for example, food tastes better when hungry, drink when thirsty, and so on. Perhaps surprisingly, even drug reward and withdrawal appear to motivate drug-taking behavior primarily via incentive modulation principles rather than directly via simple aversive drives (Stewart and Wise, 1992). Accordingly, it be- hooves affective neuroscientists to understand the neural basis of incentive properties of rewards.
Article
How do environmental factors, such as a food's visibility or convenience, influence one's consumption volume of that food? Knowing the impact of these factors could help individuals better monitor and manage consumption tendencies of which they or their families may be unaware (Rolls, Engell & Birch, 2000). Yet surprisingly little research has investigated the impact of either visibility or convenience on consumption. What has been done has generated largely inconsistent findings.
Article
Neurons in a small number of brain structures detect rewards and reward-predicting stimuli and are active during the expectation of predictable food and liquid rewards. These neurons code the reward information according to basic terms of various behavioural theories that seek to explain reward-directed learning, approach behaviour and decision-making. The involved brain structures include groups of dopamine neurons, the striatum including the nucleus accumbens, the orbitofrontal cortex and the amygdala. The reward information is fed to brain structures involved in decision-making and organisation of behaviour, such as the dorsolateral prefrontal cortex and possibly the parietal cortex. The neural coding of basic reward terms derived from formal theories puts the neurophysiological investigation of reward mechanisms on firm conceptual grounds and provides neural correlates for the function of rewards in learning, approach behaviour and decision-making.
Article
Foods sold outside the school meals program are widely available and comprise an increasing share of the foods students purchase and consume at school. Federal policies provide little regulation of foods sold outside the school meals program. State and district policies are also limited, and few specifically address fruit and vegetable availability. School-based interventions to promote consumption of fruit and vegetables among students in school settings have primarily consisted of multicomponent interventions that sometimes included an environmental intervention component. Results of these interventions have been positive, especially in their effects on fruit intake. The results of shorter term environmental interventions that used lower prices or increased availability as strategies to increase fruit and vegetable intake have been positive. Several new approaches currently being piloted in schools include school gardening programs, salad bars using fresh produce from local Farmer's Markets, and in-school, free fruit and vegetable distribution programs. Better information is needed on the economics of competitive foods and the role that financial profitability plays in decisions about food availability and sales in the school setting. Although no model programs were identified at the workshop, several promising strategies were identified to promote fruit and vegetable intake among students in school settings.
Article
Eating takes place in a context of environmental stimuli known as ambience. Various external factors such as social and physical surroundings, including the presence of other people and sound, temperature, smell, color, time, and distraction affect food intake and food choice. Food variables such as the temperature, smell, and color of the food also influence food intake and choice differently. However, the influence of ambience on nutritional health is not fully understood. This review summarizes the research on ambient influences on food intake and food choice. The literature suggests that there are major influences of ambience on eating behavior and that the magnitude of the effect of ambience may be underestimated. Changes in intake can be detected with different levels of the number of people present, food accessibility, eating locations, food color, ambient temperatures and lighting, and temperature of foods, smell of food, time of consumption, and ambient sounds. It is suggested that the manipulation of these ambient factors as a whole or individually may be used therapeutically to alter food intake and that more attention needs to be paid to ambience in nutrition-related research.
Article
The highest rates of obesity in the United States occur among population groups with the highest poverty rates and the least education. The impact of socioeconomic variables on obesity may be mediated, in part, by the low cost of energy-dense foods. The observed inverse relationship between energy density of foods, defined as available energy per unit weight (kilocalories per gram or megajoules per kilogram), and energy cost (dollars per kilocalorie or dollars per megajoule) means that diets based on refined grains, added sugars, and added fats are more affordable than the recommended diets based on lean meats, fish, fresh vegetables, and fruit. Taste and convenience of added sugars and added fats can also skew food choices in the direction of prepared and prepackaged foods. Paradoxically, attempting to reduce diet costs may lead to the selection of energy-dense foods, increased energy intakes, and overweight. The present energy-cost framework provides an economic explanation for the observed links between obesity and the food environment, with diet cost as the principal intervening variable. If higher food costs represent both a real and perceived barrier to dietary change, especially for lower-income families, then the ability to adopt healthier diets may have less to do with psychosocial factors, self-efficacy, or readiness to change than with household economic resources and the food environment. Continuing to recommend costly diets to low-income families as a public health measure can only generate frustration and culpability among the poor and less-well educated. Obesity in America is, to a large extent, an economic issue.
Article
People seem to think that a unit of some entity (with certain constraints) is the appropriate and optimal amount. We refer to this heuristic as unit bias. We illustrate unit bias by demonstrating large effects of unit segmentation, a form of portion control, on food intake. Thus, people choose, and presumably eat, much greater weights of Tootsie Rolls and pretzels when offered a large as opposed to a small unit size (and given the option of taking as many units as they choose at no monetary cost). Additionally, they consume substantially more M&M's when the candies are offered with a large as opposed to a small spoon (again with no limits as to the number of spoonfuls to be taken). We propose that unit bias explains why small portion sizes are effective in controlling consumption; in some cases, people served small portions would simply eat additional portions if it were not for unit bias. We argue that unit bias is a general feature in human choice and discuss possible origins of this bias, including consumption norms.