What Vegan Advocates Can Learn From The Social Spread Of Quitting Smoking
Background
Anyone who has been vegan for a while has likely seen how their diet and lifestyle can influence or spread to those around them. Yet if each vegan was able to create two new vegans, we would have likely seen more significant shifts in the rates of veganism (Our World In Data, 2022) in recent decades. This illustrates the difficulties of understanding social contagion—the process of information (including attitudes or behaviors) spreading throughout a group—especially in relation to veganism. By understanding social contagion better, advocates can improve their diet change outreach, possibly by mastering the art of “vegan contagion.”
One way to understand social contagion is through a social network analysis where social interactions or relationships between individuals or groups of people (e.g., countries, political parties, sport teams, etc.) are mapped out and analysed. A full network, for example, is one that outlines all social ties within a particular context, such as all students within a university. But social networks have smaller networks within them of varying strengths too, such as a romantic couple within a friend group within an acquaintance group, overlapping within a classroom and the larger university group (see figure below).
Spreading veganism or vegetarianism (combined, veg*nism)—with the long-lasting behavioral changes and beliefs it entails—requires complex contagion, which is repeated exposures by strong ties (e.g., friends and family), not just the simple spread of information (Centola, 2021). For the purpose of this review, we refer to veg*nism as a behavior (i.e., eating a plant-based diet).
Figure 1. Social Network Example
One theory, the independent cascade model, posits that change within a social network occurs at the micro-level, like between two peers, and then cascades or spreads further within the network (Hodas & Lermanm, 2014). But as mentioned above, change isn’t always that simple, and can depend upon other factors like the number of exposures to a new phenomenon and the type of relationship between the recipient and the actor. For instance, one very influential person might have the power to influence all ten of their peers, which may be more cost-effective than trying to influence ten random, less influential individuals. In other words, it may be more effective to influence people who are connected to multiple people as they act as “gatekeepers” of information and could help spread information.
The spread of veg*nism hasn’t been formally studied as of yet, but this study reflects on a similar behavior change that has been commonly studied: quitting smoking.
Why Smoking Cessation?
Quitting smoking is a good parallel to going veg*n in several ways: it’s a complex behavioral change, it’s good for one’s health (Oussalah et al., 2020) which motivates people to make the change (Faunalytics, 2021), and it’s a frequently-cued behavior. For instance, cravings (for food or nicotine), a particular time of day, or a particular environment can all remind a person of the behavior they’re trying to change. All of the cues associated with these complex behaviors make them challenging to change, and make the social environment incredibly important. For example, a smoker trying to quit may find it challenging to overcome the urge to smoke at a stressful time—imagine how much harder that is if their best friend goes out for a cigarette right then or leaves their cigarettes lying around in sight. It can be similar to going veg*n: A partner eating meat in front of you or having animal products in the house provides constant cues of the behavior you’re trying to leave behind. Some people are able to “flip the switch” and quit smoking or go veg*n overnight, but for many others there’s a period of reduction or setbacks (Faunalytics, 2021).
While smoking and animal product consumption are not perfect analogies (see the Conclusions section for more detail), the decreasing popularity of smoking may prove worthwhile for advocates to study as a template for animal product reduction. Indeed, smoking used to be widely popular, but smoking rates have fallen over the past century worldwide (Our World In Data, 2023), partly due to a combination of changing smoking norms and rising evidence of its health and environmental consequences (National Center for Chronic Disease Prevention and Health Promotion (US) Office on Smoking and Health, 2014).
Figure 2. Quitting Smoking & Quitting Animal Products
With this literature review, we examined peer influences on quitting smoking with the goal of generating hypotheses about peer-to-peer influence on veg*nism. This was an atypical review as our goal was to carefully think about what the findings for quitting smoking in a social context may suggest for going veg*n. Please note that these studies are correlational, so they can’t tell us whether someone’s behavior causes another person to change their own behavior, it can only tell us that peer behaviors are related. We believe these findings will be beneficial for both advocates working on diet change or animal product reduction as well as researchers looking to study the social contagion of veg*nism.
Key Findings*
- Romantic partners are often the strongest social ties we have, which makes them strong candidates for influencing behavior—people are anywhere between 1.3 and 11.8 times more likely to quit smoking if their partner also quits. Applied to veg*nism, this may suggest that individuals in a romantic relationship may be more likely to go veg*n together versus individually. Nonetheless, limited research on this topic has revealed that individuals in a heterosexual relationship perceive that shifting to a plant-based diet together would upset both partners and thus be challenging, although the authors also found that perceived challenges were less apparent in couples with more flexible leadership styles and left wing political ideologies (Gregson & Piazza, 2023). Thus, some couples may be better suited for targeted diet-change interventions than other couples, but more research is needed to confirm this hypothesis.
- A non-smoking partner can also serve as a good role model—people are anywhere between 1.6 and 4.4 times more likely to quit smoking if their partner is a non-smoker, while those married to current smokers are the least likely to quit. Applied to veg*nism, we speculate that omnivores may be more likely to go veg*n if their partner is veg*n instead of an omnivore, a hypothesis supported by one study to date: Couples with different diets are more open to reducing their animal product consumption than couples with a similar diet (Gregson & Piazza, 2023). Nonetheless, the dynamics of animal product consumption and gender suggest that men may have a more difficult time going veg*n than women and that a partner transitioning to a plant-based diet may cause more tension in the male partner than the female partner among heterosexual couples (Gregson & Piazza, 2023).
- After romantic couples, friends have the strongest social influence on quitting smoking. In one social network analysis, a spouse was 67% less likely to smoke if their spouse had quit smoking, 43% for mutual friends, 34% for coworkers in small firms, and 25% for siblings. Entire clusters of smokers become non-smoking clusters over time, suggesting that one’s immediate social circle influences individual behavior, especially in adulthood. In contrast, adolescents tend to be more susceptible to start smoking if their friends are smokers than to quit smoking if their friends are non-smokers. In regards to veg*nism, veg*ns are up to six times more likely to be friends with veg*ns than omnivores (Nezlek et al., 2020), which may suggest that veg*ns may have a limited social influence if their immediate social circle is already veg*n.
- Smoking is susceptible to social norms—although once widely popular, smoking rates have fallen over the past century worldwide, with smokers becoming less popular in their social networks and shifting towards the edge of their networks over time. A study that tracked smoking habits across a 32-year period, from 1971 to 2003, found that smoker clusters eventually became nonsmokers altogether, suggesting a strong peer influence to quit smoking. For instance, the percentage of daily smokers in the U.S. dropped from 30% to 15% between the years of 1980 and 2012 (Our World In Data, 2023). Applying this to veg*nism is tricky as abstaining from animal products is still a niche lifestyle with just a minority of people identifying as vegan or vegetarian (e.g., 3% of U.S. adults: Pew Research Center, 2016). Not only that, but social pressure to eat animal products (e.g., when living and/or eating with non-veg*n friends and family) has been reported as a reason why people stop eating veg*n (Faunalytics, 2023; Rosenfeld & Tomiyama, 2019). This may suggest that the social influence of veg*nism may be limited as it’s yet not a popular behavior.
- A network analysis of over 50,000 social ties, including couples, friends, and coworkers, found that the social spread of smoking drops after three degrees of separation. In other words, a person’s smoking behavior appears to be influenced by their peers’ peers’ peers, but not any further. Importantly, the social spread of smoking is weaker with each degree of separation, meaning that closer connections are associated with more influence. However, we’re not confident that this would apply to the spread of veg*nism, but it’s worth further research.
*See Table 2 for citations of the peer smoking literature.
Figure 3. Peer Influence On Quitting Smoking
Recommendations
For Advocates
Although our report mostly focused on the smoking cessation literature, our recommendations also incorporate insights from effective vegan advocacy research to help advocates best utilize peer influence to make and retain new vegans.
- Consider expanding interventions to also include social groups rather than just individuals. Human behavior is the result of myriad complex influences and interactions within social spheres. Therefore strategies to make new veg*ns need to take that into account. If we flip the above key findings, people are less likely to change if their peers don’t. This also means that the strongest ties we have are the strongest influences we can make–couples, work teams, sports teams, clubs: any of these can be untapped potential for future animal advocacy efforts.
- At the micro level, fight veg*n stigma and make veg*nism more appealing by leading as a positive example. At the individual level, animal advocates can share tasty meals with friends and loved ones (to show them that veg*n meals are delicious and accessible), be active (if it fits with your personality, to combat the stereotype that veg*ns are unhealthy), and be compassionate to peers (to fight the stereotype that veg*ns are judgy). The latter is particularly important as people’s veg*n journeys can take weeks to months and some people go veg*n for environmental and health reasons rather than animal welfare reasons. Therefore it’s important to meet people where they’re at in their veg*n journey and encourage them to continue making positive changes.
- At the macro level, leverage social norms and plant-based nudges and defaults to help normalize veg*nism and encourage behavior change. Unfortunately, veg*nism has negative associations attached to it as it’s perceived as a fringe lifestyle. People who are more susceptible to social norms may not want to be associated with a group that society deems as atypical, which may reduce the social spread of veg*nism. For this reason, advocates should communicate the dynamic norm of veg*nism to highlight how more and more people are adopting a plant-based lifestyle, which could help increase the impact of peer influence. Similarly, advocates can promote veg*nism on a large scale by changing how veg*n food is presented in grocery stores, cafeterias, and restaurants so that people are more likely to pick the plant-based option over the non-veg option.
- Create opportunities for veg*ns to make multiple, strong social connections with non-veg*ns. Connections between different groups of networks are referred to as “bridges” and these can be narrow or wide. “Narrow bridges” rely on a single point of contact, so if this connection breaks, then there’s no bridge to connect the two networks. In contrast, “wide bridges” require a group of people making multiple strong connections with another group, and even if a single connection were to break, the bridge itself will remain intact due to the other existing connections. Local meetups, like vegan festivals, are great for maintaining internal connections, but it has no parallel for building bridges that connect the movement to other social groups. Environmental and social justice groups are potential contacts with whom to explore shared goals and create “wide bridges” with. Similarly, advocates can consider maintaining friendships with non-veg*ns as much as possible to help influence them and potentially spread veg*nism. Not to mention, new veg*ns can use encouragement from veteran veg*ns to face any challenges that arise as they transition to a plant-based diet (Faunalytics, 2022).
- Don’t forget about weaker ties, like your friend of a friend of a friend (three degrees away). While we’re not sure how much influence vegan advocates have on their peers in general, the smoking literature suggests it’s possible to influence beyond your immediate social network. We previously found social media posts were able to reduce animal product consumption in meat-avoiders (e.g., flexitarians, reducetarians, and vegetarians). Such “weak ties” are still important to consider as they can transmit and receive information that you otherwise wouldn’t get through your close friends and family. Check out our infographic and resource for more information and recommendations on effective messaging on social media.
- Work towards making our movement more inclusive—social norms have a greater impact when the people referenced in the norm are similar or relevant to the observer. Also, Black, Indigenous, People of Color (BIPOC) may experience veg*n stigma more intensely than white individuals, which can make adopting a plant-based diet more challenging for them (despite the fact that BIPOC are more likely to be vegetarian than white people). Therefore, it’s essential to make our movement more inclusive of race and ethnicity, in addition to age, gender, body type, disability, and sexual orientation so that it better represents the diversity of the broader population.
For Researchers
- Conduct a social network analysis on veg*nism to better estimate the spread of eating a plant-based diet. This can take the form of a whole network study, where participants within a particular network (e.g., a school or a work company) are asked about their eating habits (to gauge whether or not they are veg*n) and people in the network with whom they have a relationship with. By mapping out all of the relationships within the network, this study design can best show the spread of veg*nism within a particular social setting, although it can be labor-intensive and time-consuming to conduct (Stark, 2017). Not to mention, this type of study can also be risky to run if the network sampled has little or no veg*ns to begin with. Instead, researchers can employ an ego-centered network study where people who are interested in going veg*n are asked to name up to five people in their personal network and answer questions about them (Stark, 2017). If veg*nism does indeed spread then participants’ should nominate at least one veg*n in their personal network. Indeed, this design is best suited to predict the strength of a veg*n’s influence over their closest peers rather than actually establishing whether or not a veg*n person causes another person to go veg*n as such studies can’t establish causation.
- Conduct an experiment to better understand the cause-and-effect of veg*nism’s social spread. The above analysis is correlational and can only tell you that two people’s behaviors are related to each other, not necessarily that one person caused another to change their behavior. Instead, researchers need to design an experiment to establish the causation of peer influence. This could involve randomly assigning, for example, two classrooms to either a control group or an experimental group. In the experimental group, only some individuals will watch a veg*n documentary (or be exposed to another type of intervention), with the remainder in this group being unexposed. If the intervention is successful, then the control group should have higher animal product consumption than the experimental group (which is the intervention effect), for example. The difference in animal product consumption (or another relevant outcome) between the control group and those who didn’t watch the documentary (or another veg*n intervention) in the experimental group is the spillover effect—i.e., the peer influence (Yang, Keller, & Zheng, 2017).
- Test a diet-change intervention between matched couples (i.e., both partners are omnivores but are interested in going veg*n) and mismatched couples (i.e., a veg*n partner serves as a role model for their omnivore partner). This design can test the hypothesis that couples who quit eating animal products together will have a higher success rate than mismatched couples. Our literature review found that couples are more likely to quit smoking if they do it together than if one partner is a nonsmoking role model for the other. Recruiting couples who are matched and mismatched in diet would allow us to investigate if this is also true for switching to a plant-based diet.
Applying These Findings
We believe that advocates who are working in individual or systemic diet change can benefit the most from this report. If you are interested in reading more about how to successfully influence diet change, here are some selected studies and resources:
- How To Make And Keep A Vegan
- Going Vegan Or Vegetarian: Many Paths To One Goal
- Bringing Back Former Vegans And Vegetarians: An Obstacle Analysis
- Vegans With Non-Vegan Partners: A Unique Dynamic
- Friends, Partners, And Dietary Similarity
- Promoting Veganism To Men: Challenges And Opportunities
We understand that reports like this have a lot of information to consider and that acting on research can be challenging. Faunalytics is happy to offer pro bono support to advocates and nonprofit organizations who would like guidance applying these findings to their own work. Please visit our Office Hours or contact us for support.
Behind The Project
Research Team
Dr. Jo Anderson (Faunalytics) stewarded this project at the start and Dr. Andrea Polanco (Faunalytics) took over the data interpretation and writing afterwards. Jared Winslow led the preregistration phase, Abby Couture contributed to the review phases, and Dung Nguyen led the review and data extraction phases.
Acknowledgements
We would like to thank Steven Rouk and Dr. Andie Thompkins for their valuable input. We would also like to thank our funders for their generous support of this research.
Research Terminology
At Faunalytics, we strive to make research accessible to everyone. We avoid jargon and technical terminology as much as possible in our reports. If you do encounter an unfamiliar term or phrase, check out the Faunalytics Glossary for user-friendly definitions and examples.
Research Ethics Statement
As with all of Faunalytics’ original research, this study was conducted according to the standards outlined in our Research Ethics and Data Handling Policy.
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Citations:
Polanco, A., Anderson, J., Nguyen, D., Winslow, J. & Couture, A. (2024). What Vegan Advocates Can Learn From The Social Spread Of Quitting Smoking. Faunalytics. https://faunalytics.org/what-vegan-advocates-can-learn-from-the-social-spread-of-quitting-smoking/
