Data from 9,319 adult Finnish twins and siblings of twins: Abstention from meat (i.e., vegetarianism/veganism) was 75% heritable

Çınar, Çağla, Laura Wesseldijk, Annika Karinen, Patrick Jern, and Joshua M. Tybur. 2021. “Sex Differences in the Genetic and Environmental Underpinnings of Meat and Plant Preferences.” PsyArXiv. September 27. doi:10.31234/osf.io/7mxar

Abstract: People vary in the degree to which they enjoy eating meats versus plants. This paper examines the genetic and environmental roots of this variation, as well as the genetic and environmental roots of meat neophobia, plant neophobia, and vegetarianism/veganism. Using data from 9,319 adult Finnish twins and siblings of twins (551 MZ, 861 DZ complete; 783 MZ, 2,692 DZ incomplete twin pairs), we examine the degree to which recalled childhood exposure to meats and plants relates to adult preferences for the same meats and plants. We also investigate sex differences in the heritability of 1) meat and plant preferences, 2) childhood meat and plant consumption, 3) meat and plant neophobia, and the heritability of 4) vegetarianism/veganism. For both men and women, recalled childhood meat consumption correlated more strongly with current meat preferences than current plant preferences, and recalled childhood plant consumption correlated more strongly with current plant preferences than current meat preferences. We detected sex differences in the heritability of childhood meat consumption (h2men= .31, h2women= .11) and current meat preferences (h2 men = .26, h2women =.51), but not childhood plant consumption (h2men= .41, h2women =.17), current plant preferences (h2men = .45, h2women =.53), meat neophobia (h2men = .48, h2women = .55) or plant neophobia (h2men = .56, h2women = .54). Further, different genes undergirded men’s and women’s meat preferences. Abstention from meat (i.e., vegetarianism/veganism) was 75% heritable. These results have implications for hypotheses of the developmental origins of dietary patterns and hypotheses for sex differences in meat consumption.