The present study examined changes in the rates of vegetarianism among a sample of young American adults. Over 15 years, students at an American university (N = 12,704) described their dietary habits. Multilevel modeling analyses (participants nested within semesters) found that overall, the percentage of vegetarians increased over time, whereas the percentage of omnivores decreased over time; however, these changes occurred only for women. The dietary habits of men did not change over time. In a second study, in a sample of 363 adult vegetarians from the US, we found that women were more likely than men to become vegetarians due to concerns about the ethics of raising animals for food and eating them, suggesting that increased societal concern about animal rights may be responsible in part for the gender differences over time in vegetarianism. These results extend existing research on gender differences and suggest that if current trends continue, gender differences in vegetarianism may be more pronounced in the future.

本研究调查了美国年轻人样本中素食率的变化。 15 年来，一所美国大学的学生 ( N = 12,704) 描述了他们的饮食习惯。多层次建模分析（参与者嵌套在学期内）发现，总体而言，素食者的比例随着时间的推移而增加，而杂食者的比例随着时间的推移而下降；然而，这些变化只发生在女性身上。男性的饮食习惯并没有随着时间的推移而改变。在第二项研究中，我们对来自美国的 363 名成年素食者进行了抽样调查，结果发现，由于担心饲养动物作为食物并食用它们的道德问题，女性比男性更有可能成为素食者，这表明社会对动物的关注增加随着时间的推移，素食主义中的性别差异可能是由权利造成的。这些结果扩展了现有的关于性别差异的研究，并表明如果当前的趋势持续下去，素食主义的性别差异在未来可能会更加明显。