Dominic Favre / AP

In the past couple of decades, vegetarian diets have achieved enormous visibility in the United States. Consumers now include more plant-based foods in their diet, as sales of these foods continue to rise. But the extent to which vegetarianism and veganism have led Americans to actually give up eating meat remains unclear. The U.S. Department of Agriculture has estimated that 2018 will be the United States’ biggest year for meat consumption yet. A recent Gallup poll found that only 5 percent of Americans identify as vegetarian and 3 percent identify as vegan, signaling little to no growth in the movement from 2012.

In a new study, Corey Wrenn, a sociologist at Monmouth University and an outspoken advocate for veganism, puts forth a theory for how the vegan movement could be more successful—and uses it to illustrate how social movements in general tend to undermine their own progress. There are many reasons social movements across the spectrum can have difficulty retaining members, she says: social stigma, risk of arrest, or even because members don’t want to bother with bad weather or calling politicians. So how does a movement attract more people while staying true to its core principles?

Wrenn finds that many organizations behind social movements loosen the expectations they have of their followers, allowing people to identify with the cause without actually changing their behavior. But this relaxed approach, she argues, jeopardizes the movement as a whole.

Take “flexitarians,” people who are interested in vegetarianism but still eat meat. Under Wrenn’s critical eye, flexitarians are an example of what she calls “free riders”: passive participants of a social movement who benefit from the work core members put into the cause. While permitting free-rider participation in a movement may extend its longevity, she contends, it ultimately weakens it by diluting a social movement’s message and making it more difficult for a movement to mobilize resources. An influx of free riders, Wrenn says, “maintain[s] the illusion of mass support, [while] real power is reserved for core members.”

“Those eating flexitarian aren’t really eating any less animal products,” Wrenn says. “Other research finds that participants asked to eat prescribed diets of omnivorism, flexitarianism, and veganism experienced similar levels of satisfaction and adherence to the diet. So why not go for the gold and ask folks to go vegan?”

Wrenn points to 25 studies she says showcase the shortcomings of allowing flexitarianism or an unstructured “incremental” conversion to veganism. A 2012 study of Canadian vegetarians and ex-vegetarians found that flexitarians who quit eating meat because of health or environmental reasons were more likely to relapse to meat eating. A 1993 British study found that only a quarter of people who considered themselves to be reducing meat intake actually did.

For an example of successfully encouraging consumers to give up something they love, Wrenn says, look to smoking-cessation campaigns. One 2007 study found that smokers are more likely to quit when they’re either asked to stop smoking immediately or put on a specific, scheduled smoking-reduction plan, as opposed to simply being asked to “cut back.” (The percentage of adults in the United States who smoke declined from 20.9 percent in 2005 to 15.5 percent in 2016.)

Despite Wrenn’s findings, history has shown that in some cases, slower, more incremental change has benefitted the vegan movement. Elizabeth Cherry, the author of Culture and Activism: Animal Rights in France and the United States, notes that a more practical, gradual approach worked for the American vegan movement, beginning in the ’90s. “I found that the U.S. [vegan movement] used a cultural logic of pragmatism, meaning they just used whatever worked, regardless of whatever they may personally think about it,” such as appealing to people’s concerns about health, she says. The French vegan movement, meanwhile, “chose from their tools using a cultural logic of consistency, meaning that they only used the tools that exactly aligned with their beliefs.”

This limited method meant less success for the French vegan movement, Cherry says. But she observes that the vegan movement has indeed stalled. She claims that people sometimes identify as vegetarian without significantly reducing or eliminating animal products from their diet, and notes the U.S.’s all-time-high meat consumption. She also argues that many flexitarian organizations don’t actually encourage people to eat less meat; they merely encourage them to eat more other things, which might not end up in people actually reducing their meat intake.

Nevertheless, Cherry says she’s not 100 percent convinced that by promoting meat reduction, the vegan movement is setting itself up for failure. “I interviewed almost 100 vegans or vegan animal-rights activists and most of them went vegan in stages rather than all at once, so I don’t think that accepting veganism as the end stage of several other steps is actually a problem for the animal-rights movement,” she says.

Gene Baur, the president of the animals-right nonprofit Farm Sanctuary, says that incrementalism can work in most cases, especially when it’s not just people’s hearts you’re trying to change, but a social and economic system. In the ’90s, Farm Sanctuary reached out to local restaurants, urging them to serve more plant-based foods. One of those local restaurants was Burger King. “They decided to sell a veggie burger, and that became a nationwide veggie burger,” Baur says. “So in my mind, Burger King having a veggie burger is a good thing when it comes to promoting the goal of plant-based eating.”

When California’s Proposition 2, which placed regulations on how tightly animals are allowed to be packed into cages, passed in 2008, Baur adds, “there was a decline in meat consumption and, generally speaking, a decline in animal production.”

Still, Baur acknowledges that meat consumption rose this year, an issue he thinks stems from the huge agricultural industry. “When these foods are cheap and accessible and highly marketed, people tend to eat them,” he says.

Nina Gheihman, a doctoral student at Harvard who studies veganism, agrees with Wrenn’s findings that flexitarianism, as an acceptable end goal within the vegan and vegetarian movements, is damaging. But Gheihman says that the movement should be welcoming to those at its boundaries who may not be ready to dive right into veganism. “I do believe that flexitarianism as an initial approach is worthwhile, as there are many people who are not willing to adopt the ideological stance of the animal-rights movement within a society that does not yet embrace it. As well, they may have alternate motivations for following a plant-based diet, including health and environmentalism, and I believe these motivations are as valid as that of animal rights.”

In Wrenn’s view, “becoming bureaucratic” stifles social movements’ “ability to create meaningful social change.” But Baur argues that it’s more complex than that: Some organizations do become successfully bureaucratic, bigger, and more mainstream, while others lose integrity and are co-opted. “It is personal and also systemic and structural,” he says. “It’s a legitimate thing to be aware of and concerned about, but I don’t think it applies across the board.”

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