Previous research has identified three common motives that drive people to adopt plant-based diets — health, environmental concerns, and animal rights — which are measured by the Vegetarian Eating Motives Inventory (VEMI). However, these three motives alone can’t fully explain the diversity of dietary choices.

This study expands the framework by introducing four additional motives: disgust, social influences, concerns about zoonotic diseases and pandemics, and workers’ rights. Together, these seven motives form the foundation of the Veg*n Eating Motives Inventory Plus (VEMI+), an update of the VEMI designed to provide a more comprehensive understanding of what drives people to reduce their meat consumption.

The researchers had three objectives:

1. To test whether all seven motives (health, environmental concerns, animal rights, disgust, social influences, concerns about zoonotic diseases and pandemics, and workers’ rights) could be combined into a robust model;
2. To check if the VEMI+ works the same way for both vegans and omnivores; and
3. To validate the seven motives by comparing them to other well-known measures and seeing how they influence people’s reactions to specific meat-reduction messages.

The study included 1,462 participants mainly from North America, recruited via the Prolific platform, and evenly divided between omnivores and vegans. To ensure balance, the two groups were matched based on age, gender, race, and ethnicity.

To create the VEMI+, researchers used statements from the original VEMI to measure health, environmental, and animal rights motives, as well as new statements based on a literature review and designed to measure motives related to disgust, social influences, concerns about zoonotic diseases and pandemics, and workers’ rights. Participants were asked to rate the importance of each statement on a seven-point scale.

In addition, vegan participants completed other pre-established scales that measured similar concepts, such as the “Need to Belong” scale which was comparable to the social influences motive. Vegan participants were also asked to rate the persuasiveness of seven different meat-reduction messages, each one aligned to a specific VEMI+ motive, on a five-point scale.

The study achieved its three main goals:

• First, analysis revealed that 21 of the 35 statements in the VEMI+ were the most reliable in capturing the seven motives. These were used in the final model.
• Second, the actual results of the VEMI+ showed a number of expected differences between vegans and omnivores. Vegans scored higher overall, especially on motives like disgust, animal rights, and environmental and disease concerns. Omnivores scored slightly higher on social influence, workers’ rights, and health motives.
• Third, correlations were found between the seven motives and their corresponding external scales and targeted meat-reduction messages. This confirmed that, overall, the VEMI+ measures what it was designed to measure.

Beyond developing and validating the VEMI+, the results highlighted that motives for plant-based diets are widely shared, with distinctions between omnivores and vegans being primarily about intensity rather than type. Vegans aligned more with “external orientations” (ethical veganism), while omnivores leaned toward “internal orientations” (self-serving veganism). Notably, disgust and workers’ rights emerged as distinct motives differentiating the two groups.

The study also found that these motives are not mutually exclusive. Disgust avoidance correlated with health and disease concerns, suggesting it as an adaptive trait that could encourage plant-based eating, similar to strategies used in anti-tobacco campaigns. The results highlight the diversity of motives within the vegan community as well. For example, some vegans may be driven more by ethical concerns, while others focus on health or social reasons. This deeper understanding provides a more nuanced view of the vegan community.

This study faced a few limitations. The sample included only omnivores and vegans from Western populations, excluding intermediate dietary groups such as vegetarians and making it harder to apply the findings to other cultural contexts. The use of self-reported data may have introduced biases, where participants felt compelled to report less meat consumption due to perceived social desirability. Additionally, the meat-reduction messages were tested only on vegans, so their effect on omnivores remains unknown. The study didn’t explore how dietary motives connect to psychological traits or how personalized appeals influence behavior. Future research should address these gaps by including more diverse groups and using real-world behavioral data.

Despite these limitations, a number of general strategies to encourage plant-based eating emerge from the findings:

• Use disgust-based messaging to explore its potential in reducing meat consumption;
• Design tailored advocacy campaigns targeting specific motives; and
• Develop interventions informed by the diversity of motives within the vegan community.

While omnivores and vegans share similar motivations for reducing meat consumption, the strength of these motives varies between the two groups. By exploring these differences, the study sheds light on the diversity within the vegan community and offers valuable guidance for creating tailored strategies to inspire more people to adopt plant-based eating.