Sociology graduate student Nina Gheihman is researching social aspects of veganism’s spread. Veganism was at first closely bound to the ideology of the animal-rights movement, she explains, which initially aimed at a range of targets, like wearing fur and testing products on animals. Once activists shifted focus to farm conditions and food, veganism took on the features of what scholars call a “lifestyle movement.” Over time, it’s become more closely associated with general environmental concerns and a “healthism” mentality, bound up with notions of perfecting the body. Trustworthy numbers on how many people identify as vegan are hard to come by, says Gheihman, but a growing number practice veganism in some way: incorporating meat and dairy substitutes in their meals, or restricting their diets at certain times of day or for a period of weeks.