New research indicates that the fundamental values of vegetarians differ from those of non-vegetarians in consistent ways, suggesting that choosing a vegetarian diet is an expression of independence. The study, published in the scientific journal PLOS One, found that across American and Polish populations, vegetarians tended to prioritize values related to personal achievement and stimulation while placing less emphasis on tradition and conformity.
The study was conducted by researcher John B. Nezlek of SWPS University and the College of William & Mary. The rationale for the investigation stemmed from a gap in the existing scientific literature. While many studies have examined specific attitudes related to vegetarianism, such as concerns for animal welfare or the environment, less research has focused on how this dietary choice connects to a broader, more fundamental set of basic human values. The researcher noted that these basic values are abstract ideals that are thought to guide a wide range of a person’s attitudes and behaviors.
Nezlek also pointed out that previous studies often treated meat consumption on a simple continuum from high to low. He argued that this approach overlooks the reality that vegetarianism is a distinct social identity. People who simply reduce their meat intake are not the same as those who adopt a vegetarian identity. The present study was designed to specifically compare individuals who identify as vegetarians with those who do not, treating these as separate groups to better understand the underlying value systems that might distinguish them.
To explore these differences, the researcher analyzed data from three separate studies involving adults from general populations. One study was conducted in the United States, and two were conducted in Poland. To ensure a large enough group for meaningful comparison, vegetarians were intentionally oversampled in the American study, which included 514 vegetarians and 540 non-vegetarians. A similar oversampling method was used in one of the Polish studies, which comprised 301 vegetarians and 335 non-vegetarians. The second Polish study drew from a more general sample, resulting in 68 vegetarians and 1943 non-vegetarians.
In all three studies, participants were first asked to describe their dietary habits. They chose from a list of options such as vegan, lacto-ovo-vegetarian, pescatarian, omnivore, and others. For the main analysis, individuals who identified as vegan, plant-based, lacto-vegetarian, or lacto-ovo-vegetarian were classified as vegetarians. All other participants, including pescatarians, semi-vegetarians, and omnivores, were grouped as non-vegetarians.
Participants then completed a version of Schwartz’s Portrait Value Questionnaire, a widely used tool in psychology for measuring basic human values. This questionnaire presents descriptions of different people and asks respondents how similar that person is to them. The responses are used to measure the importance of ten basic values: Universalism, Benevolence, Tradition, Conformity, Security, Power, Achievement, Hedonism, Stimulation, and Self-direction. The researcher performed statistical analyses to compare the value scores between vegetarians and non-vegetarians, while also accounting for potential differences related to gender.
Across all three studies in both countries, a consistent pattern of differences emerged. Vegetarians consistently placed less importance on the values of Benevolence, which relates to preserving the welfare of people in one’s close circle, and Security, which concerns safety and stability in society and relationships. The value of Conformity, which involves restraining actions that might upset or violate social expectations, was also less important for vegetarians in all studies, though this difference was only marginally significant in the American sample.
Similarly, vegetarians in all three studies endorsed Tradition values less strongly than non-vegetarians. This value emphasizes respect for and commitment to cultural or religious customs and ideas. While this pattern was clear in both Polish studies, the difference did not reach statistical significance in the American study.
In the opposite direction, several values were consistently more important to vegetarians. Across the American and Polish samples, vegetarians placed a higher priority on Stimulation, a value reflecting a desire for excitement, novelty, and challenge in life. They also endorsed Achievement values more strongly, which center on personal success through demonstrating competence according to social standards. Likewise, vegetarians consistently rated Power, a value related to social status, prestige, and control over people and resources, as more important than non-vegetarians did.
Only one value showed a different pattern depending on the country. In the United States, Self-direction, which prioritizes independent thought and action, was more important for non-vegetarians than for vegetarians. In Poland, the opposite was true, with vegetarians placing a higher importance on Self-direction than non-vegetarians. The reasons for this cultural divergence were not immediately clear from the data. The researcher also found very few instances where the differences in values between vegetarians and non-vegetarians were affected by a participant’s gender.
These findings suggest that following a vegetarian diet may be a manifestation of a value system that prioritizes individuality and a willingness to stand apart from the majority. By choosing a diet that is not the norm in most Western societies, vegetarians may be expressing a commitment to personal beliefs over social convention. This interpretation contrasts with some common gender-based stereotypes that might associate vegetarianism with more stereotypically feminine traits like benevolence and harmony. The results here suggest that, in terms of basic values, vegetarians may actually be more aligned with principles of achievement and personal drive.
The study did have some limitations. Because the data were collected at a single point in time, it is not possible to determine whether holding certain values leads a person to become a vegetarian, or if the act of becoming a vegetarian changes a person’s values over time. The research was also confined to the United States and Poland, so the findings may not apply to other cultures where vegetarianism has different historical and social meanings. Future research could explore these questions with studies that follow people over time or that include more diverse cultural groups.
Additionally, the study’s exploratory analyses of different types of diets, such as comparing vegans to other vegetarians or occasional omnivores to full omnivores, did not reveal consistent patterns. This suggests that the primary distinction in values may lie between those who eat animal flesh and those who do not. However, the researcher noted that these explorations were not the main goal of the study and that more focused research is needed to understand the values of people who reduce meat consumption without becoming fully vegetarian. The results provide a new path for understanding the psychology of dietary choices, connecting them to the deep-seated principles that guide people’s lives.
The study, “Rethinking vegetarianism: Differences between vegetarians and non-vegetarians in the endorsement of basic human values,” was published May 28, 2025.
