LONDON — It seemed like the perfect pitch to a popular British food magazine that had recently reported on an increase in sales of plant-based food: a new series about veganism.
But the editor of the magazine, Waitrose Food, was not at all impressed by the idea put forward last week by the freelance writer, and he responded with a proposal of his own that led to howls of outrage and his swift resignation from the magazine.
“How about a series on killing vegans one by one,” the editor, William Sitwell, wrote in an email seen by The New York Times. “Ways to trap them? How to interrogate them properly? Expose their hypocrisy? Force-feed them meat? Make them eat steak and drink red wine?
Selene Nelson, the vegan food writer who had sent the pitch to the upscale grocery store’s magazine ahead of World Vegan Day on Thursday, said that while she frequently came across people with hostile attitudes toward veganism, she had “never seen anything like this.”
“I’ve written about many divisive topics, like capital punishment and murder cases and domestic violence, and I’ve never had a response like that to any of my articles or pitches,” she said in an interview with Buzzfeed News.
The email stirred up enough outrage that Mr. Sitwell apologized, said it was all a joke and stepped down from his position on Wednesday.
On Instagram, he offered an apology “to any food- and life-loving vegan who was genuinely offended by remarks written by me as an ill-judged joke in a private email and now widely reported.”
But Waitrose said in a statement, “Even though this was a private email, William’s gone too far, and his words are extremely inappropriate, insensitive and absolutely do not represent our views.”
The spat came at an awkward time for the food retailer, which recently announced an exclusive range of vegan products after reporting that it sales of vegan and vegetarian products had risen 85 percent since last year.
Mr. Sitwell’s comments, said in jest or not, appear to be out of touch with shifting attitudes of the British public. Britons are increasingly substituting meat with plant-based products.
In Britain, which had a population of 66 million in 2017, about 600,000 people identify as vegan, up from 540,000 in 2016, according to the Vegan Society, though some groups put the figure higher. (A widely reported statistic of more than 3.5 million vegans in Britain sprang from the comparison website Compare the Market. Published this year, it was based on a survey of 2,000 people.)
“Just the fact that the Brits have made vegan fish and chips show that veganism is being accepted by the mainstream,” said Dan Butler, a vegan who traveled an hour across London to try the city’s first Vegan fish and chips shop.
“There has been a shift in attitudes,” Mr. Butler said. “People don’t dismiss veganism or mock vegans like they used to.”
Vegans don’t consume any animal products, including eggs and dairy. More than 60 percent of vegans (and 40 percent of vegetarians) surveyed for a Waitrose report said they had adopted their new eating habits over the past five years out of concern for their health, the environment and animal welfare. That tracks with other reports on the growing global shift away from meat-based products.
Research published in the journal Science this year says that avoiding meat and dairy products is the single biggest way to curb environmental damage to the planet. The loss of wild areas to agriculture is the leading cause of the current mass extinction of wildlife, scientists say.
Mr. Sitwell had his defenders, such as the food critic at The Times, Giles Coren, who said that while the email was “stupid,” it should not have been a “career ender.”
“Vegans are not a race or a gender or a sexual orientation or a differently abled group,” he wrote in a tweet. “They just choose to eat plants.” He said someone should be able to poke fun at vegans “and not lose your job.”
It is not the first time that Mr. Sitwell has been critical of the uptick in veganism. In an article published in The Times of London in January, he wrote:
“It had slow beginnings among shampoo-averse hippies in the 1970s, but now vegans are parking their tanks on all of our lawns and their instruction manuals are coming like propaganda pamphlets dropping from the sky.”
