Hodson and Earle, (2018)
For every 1-point increase in a 5-point scale (liberal to conservative), there was a 26% increase in the odds that one lapsed back to eating meat. Conservatism predicted quitting vegan controlling for age, education, and gender. This is because cons a) did not adopt veg*n diets for reasons of social justice, such as animal welfare; and (b) felt poorly supported in their social circles (family and friends). It was not because they craved meat more, or worried more about their health.