The art of dieting: Exposure to thin sculptures effortlessly reduces the intake of unhealthy food in motivated eaters

Effectiveness of visual nudges for encouraging healthier beverage choices from vending machines

ISSUES ADDRESSED

Research suggests visual nudging techniques can subtly encourage healthier consumption. Two experiments explored the effect of four visual primes for nudging drink choices from a vending machine display.

METHODS

Participants (17-25 years) were randomly assigned to view vending machine advertising posters containing pictorial nudges of water, soft drink, general health (runner), or a text-only control, for nudging vending machine choices. Participants then selected an item from a vending machine display containing drinks only (Experiment 1; n = 164), or both drinks and snack foods (Experiment 2, n = 684).

RESULTS

In both experiments, nudging condition predicted beverage choice. Specifically, the water image nudged healthier beverage choices in both experiments. However, there was no effect on food choice in Experiment 2. Furthermore, in both experiments, liking and habitual consumption of chosen items were also significant predictors of choice, but condition predicted beverage choice over and above these.

CONCLUSION

A water prime may be an effective means of encouraging healthier beverage choices in a vending machine environment. SO WHAT?: Findings have the potential to inform strategies for encouraging healthier beverage choices from vending machine environments.

Exploring Whether Weight-Related Cues Affect Food Intake in Older Adults with Dementia

Purpose

Past research has shown that exposure to the image of a slim person reduces food consumption among young adults. However, it remains unknown whether this paradigm could be adapted and applied to increase food intake among older adults with dementia by exposing them to the image of a higher-weight person to mitigate weight loss and malnutrition. The present study explored whether weight-related visual cues affect the amount of food consumed by older adults with dementia.

Participants and Methods

In the experiment, twenty-one elderly people with dementia living in a nursing home were visually exposed to one of four conditions (a cartoon image of a normal-weight chef, a higher-weight chef, a flower or no image) during real-life daily lunch situations over the course of four weeks, during which each condition was presented for one week.

Results

Results demonstrate that participants finished their meals more frequently when they were exposed to the image of the higher-weight chef than when they were not exposed to any images.

Conclusion

These results suggest that exposure to a cartoon chef character representing a stereotyped social group related to body weight activates the stereotype and increases stereotype-consistent behavior in older adults with dementia. The present findings will contribute to understanding the effect of visual information on eating behavior and to designing eating environments which facilitate sufficient nutrition intake among older adults with dementia.

Effects of a Nudging Cue Targeting Food Choice in a University Cafeteria: A Field Study

Many students approaching adulthood often choose high-calorie food products. Concurrently, health interventions applied during this life phase can potentially lead to a healthier lifestyle. Nudge health interventions in experimental cafeteria settings have been found to improve eating behavior effectively, yet research in real-world settings is lacking. Accepting nudges as health interventions impacts nudge effectiveness. The present study applies a pretest-posttest design for a period of three consecutive weeks (no nudge, nudge, no nudge), testing the effectiveness of the so-called Giacometti cue on the number of calories purchased in a real-world cafeteria. Students were exposed to the nudge during the intervention week when entering the cafeteria and when choosing their meals. After purchasing a meal, their choice was recorded, and they completed a questionnaire. The Giacometti cue immediately reduced the number of calories purchased (comparing weeks one and two). After nudge removal, an effect was identified, increasing the number of calories purchased (comparing weeks two and three). Contrary to expectations, higher nudge acceptance resulted in more calories purchased. Neither awareness of the nudge's presence when buying food nor the interaction between acceptance and awareness played a role. We explore potential explanations for the Giacometti cue's effects.

Cafeteria Online: Nudges for Healthier Food Choices in a University Cafeteria-A Randomized Online Experiment

Many people do not consume as much healthy food as recommended. Nudging has been identified as a promising intervention strategy to increase the consumption of healthy food. The present study analyzed the effects of three body shape nudges (thin, thick, or Giacometti artwork) on food ordering and assessed the mediating role of being aware of the nudge. Students (686) and employees (218) of a German university participated in an online experimental study. After randomization, participants visited a realistic online cafeteria and composed a meal for themselves. Under experimental conditions, participants were exposed to one out of three nudges while choosing dishes: (1) thin body shape, (2) thick body shape, and (3) the Giacometti artwork nudge. The Giacometti nudge resulted in more orders for salad among employees. The thin and thick body shape nudges did not change dish orders. Awareness of the nudge mediated the numbers of calories ordered when using the Giacometti or thin body shape nudges. These findings provide useful insights for health interventions in occupational and public health sectors using nudges. Our study contributes to the research on the Giacometti nudge by showing its effectiveness when participants are aware (it is effective under conditions where it is consciously perceived).

Changing your body changes your eating attitudes: embodiment of a slim virtual avatar induces avoidance of high-calorie food

The virtual-reality full-body illusion paradigm has been suggested to not only trigger the illusory ownership of the avatar's body but also the attitudinal and behavioral components stereotypically associated to that kind of virtual body. In the present study, we investigated whether this was true for stereotypes related to body size: body satisfaction and eating control behavior. Healthy participants underwent the full-body illusion paradigm with an avatar having either a larger or a slimmer body than their own, and were assessed for implicit attitudes towards body image and food calorie content at baseline and after each full-body illusion session. Results showed that the illusion emerged regardless of the avatar's body size, whereas the perceived dimension of the own body size changed according to the avatar's body size (i.e., participants felt to be slimmer after embodying their slim avatar and larger after embodying their large avatar). Crucially, we found that implicit attitudes towards food, but not those towards one's own body, were modulated by the size of the virtual body. Compared to baseline, ownership of a slimmer avatar increased the avoidance of high-calorie food, whereas ownership of a larger avatar did not induce changes. Our findings suggest that the illusory feeling of being slimmer drives also the food-related stereotypes associated with that body size, increasing the regulation of eating behaviors.

Targeting automatic processes to reduce unhealthy behaviours: a process framework

While previous frameworks to address health behaviours through targeting underlying automatic processes have stimulated an improved understanding of related interventions, deciding between intervention strategies often remains essentially arbitrary and atheoretical. Making considered decisions has likely been hampered by the lack of a framework that guides the selection of different intervention strategies targeting automatic processes to reduce unhealthy behaviours. We propose a process framework to fulfil this need, building upon the process model of emotion regulation. This framework differentiates types of intervention strategies along the timeline of the unfolding automatic response, distinguishing between three broad classes of intervention strategies - direct antecedent, indirect antecedent, and response-focused. Antecedent-focused strategies aim to prevent the exposure to or activation of automatic responses directly through the avoidance of unwanted stimulus-response associations (i.e., situation modification or situation-specific response selection), or indirectly through automatising self-control (i.e., attentional deployment or cognitive change). Response-focused strategies aim to directly downregulate automatic unwanted responses (i.e., response modulation). Three main working hypotheses derived from this process framework provide practical guidance for selecting interventions, but await direct testing in future studies.

A Dieting Facilitator on the Fridge Door: Can Dieters Deliberately Apply Environmental Dieting Cues to Lose Weight?

Individuals exposed to dieting-related environmental cues have been repeatedly shown to be better able to resist tempting food. This especially applies to restrained eaters who hold a chronic dieting goal. Thus far, mainly short-term effects of environmental dieting cues have been examined and the individuals were typically unaware of being influenced. Yet, it is unclear whether individuals can deliberately apply environmental dieting cues for themselves to facilitate the pursuit of the longer-term goal of losing weight. The present longitudinal study applied a 2 (cue: visually dieting-related vs. visually neutral cue) × 2 (awareness: being aware vs. not being aware of the cue’s facilitating influence) between-subjects design for 6 months (N = 166 participants who started the study; M_age = 47.85 years; 69.9% female; M_BMI = 29.07 kg/m²). Our results provide preliminary indications that cue, awareness, and restrained eating interact. The results suggest that high (vs. low) restrained eaters could deliberately apply environmental dieting cues for themselves to facilitate losing weight. However, further studies are needed to explore the effects of environmental dieting cues over a longer period of time.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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