Generated Summary
This study investigates the impact of plant-based defaults on dining practices within college campuses. The research employs a field experiment conducted in three private research university cafeterias over three months. The methodology involved randomizing one dining station per cafeteria to either a plant-based default or a no-default control condition each day. The primary hypothesis tested whether plant-based defaults would increase the servings of vegan dishes compared to meat-containing dishes and whether there would be a simple effect of the condition on the sale of vegan and meat dishes. The study aimed to assess the effectiveness of vegan defaults in reducing meat consumption, addressing the limitations of prior research by including a no-default control, analyzing the consumption of both vegan and meat dishes, and examining the impact in a real-world dining setting. The intervention involved displaying vegan dishes first on the menu with meat options available upon request. The research collected data on the total number of meat and vegan dishes served each day at the experimental stations. The study’s objective was to provide insights into the practical implications and effectiveness of plant-based defaults in promoting more sustainable dietary choices.
Key Findings & Statistics
- The study observed a total of 15,278 servings across all sites during the intervention period.
- Meat dishes accounted for 8,741 servings (57.2%), while plant-based dishes made up 6,537 servings (42.8%) across all stations.
- There was a statistically significant interaction between dish type (meat or vegan) and the default condition (control or plant-based default).
- Compared to control days, the plant-based default days showed a 58.3% increase in vegan dish servings, confirming hypothesis H2a.
- Plant-based default days also had a 57.2% decrease in the number of meat dishes served, confirming hypothesis H2b.
- On control days, meat dishes servings were significantly more than vegan dishes, while on plant-based default days, more vegan dishes were served than meat dishes, though the difference was not statistically significant.
- A 26.1% reduction in total servings was observed on plant-based default days.
- Even in a worst-case scenario where all patrons selecting plant-based dishes chose meat elsewhere, there would still be an estimated 21.4% reduction in meat dishes sold.
- Power analysis indicated the study was 80% powered to detect a medium-large effect size (Cohen’s d = 0.6).
- The intervention was implemented over 65 days across three sites.
- The effect size for the overall intervention was 0.22, with p < .001.
- The effect size for simple effects of condition for meat dishes was -113.63, with p < .001.
- The effect size for simple effects of condition for vegan dishes was 42.62, with p = .036.
- The effect size for meat dishes on control days was -125.70 with p < .001.
- The effect size for meat dishes on plant-based days was 30.55, p = .122.
Other Important Findings
- The study found that a vegan default intervention was able to reduce meat servings and increase vegan dishes served in college cafeterias.
- The intervention showed an improvement in satisfaction with vegan dishes on default days, though this could be due to self-selection.
- There was a reduction in total servings on the plant-based default days which could be related to some diners choosing meat elsewhere.
Limitations Noted in the Document
- The sales data was collected by day and station, not by individual diner, which limits understanding of individual behavior changes.
- The study was conducted on college campuses using a rotating menu, so the results may not apply to other dining contexts with different menus or settings.
- The study used two methods of setting a default (requesting the alternative and visibility of the alternative), making it unclear which feature was most effective.
- The intermittent exposure to control and default interventions may weaken the default’s impact compared to a consistent intervention.
- The study’s sample might have been more predisposed to trying vegan dishes, which may limit the generalizability of the results.
Conclusion
In conclusion, this research demonstrates that plant-based defaults can significantly shift consumer behavior toward more sustainable dietary choices. The study’s findings support the use of plant-based defaults in reducing meat consumption within communal dining settings, specifically within college cafeterias. The plant-based default intervention led to a substantial increase in vegan dish consumption and a decrease in meat dish consumption. The authors note the results of default interventions may have limitations. Even though the total number of servings decreased, the intervention still reduced meat consumption. The authors suggest that the industry can take action for climate goals and support dietary change with default interventions in live-dining settings. The researchers state, “Reducing our consumption of animal products is a key part in meeting our sustainability goals, and dietary default interventions can play a significant role in promoting these shifts in behavior.”