FOR YEARS Britons intent on a virtuous start to the year have pledged to observe an alcohol-free “Dry January”. These days, however, a trendier resolution is to swear off meat. This month, according to Google Trends, there were about as many British searches for “Veganuary”—in which participants adopt a vegan diet for a month—as for “Dry January” for the first time. Veganuary UK, the charity behind the annual campaign, says 350,000 signed up this year, up from 250,000 in 2019. Just how many have stuck to their commitment is anyone’s guess.

Enthusiasm for veganism is not limited to Britain. If Google searches are any guide, interest in the plant-based diet has surged in recent years across much of the rich world. Since 2015, searches for “veganism” have doubled in America and tripled in Australia, France and Spain. In Sweden, home to the 17-year-old climate activist, Greta Thunberg, searches have more than quadrupled (see chart). Eating habits are changing, too. Ipsos MORI, a pollster, reckons that the number of vegans in Britain quadrupled between 2014 and 2018, from 150,000 to 600,000, a little over 1% of the adult population. In America roughly 2% of adults consider themselves vegans, according to YouGov, another pollster. Another 5% identify as vegetarians and 3% as pescatarians.

But the notion of part-time veganism—implicit in a pledge of a meat-free month—is controversial. For staunch vegans who abstain from animal products for ethical reasons, killing animals is wrong every day of the year. Surveys suggest that newcomers to veganism are less interested in animal welfare than in perceived health benefits or in concern for the planet, a sign that part-time veganism might grow in popularity. According to YouGov, about 59% of Americans who are eating less meat than they were a year ago are doing so mainly for health reasons; another 10% cite climate change as their primary motivation. Just 9% are cutting back out of concern for animal welfare. Among those aged 18-29, concern about the climate is much higher, at 24%. Among this younger group, only 5% cite animal welfare for eating less meat—less than the 6% of respondents who are doing so “because it is trendy”.