An increasing proportion of people choose to follow a vegetarian diet. To date, however, little is known about if and how individual differences in personality relate to following a vegetarian diet. In the two studies presented here, we aimed to (1) estimate the prevalence of self-defined vegetarians in two waves of a German representative sample (N = 4,496 and 5,125, respectively), (2) analyze the effect of socio-demographic variables on dietary behavior, and (3) examine individual differences between vegetarians and meat eaters in personality traits, political attitudes, and health-related variables. In Study 1, a strict definition of vegetarians was used, while in Study 2 the definition was laxer, to include also individuals who only predominantly followed a vegetarian diet. The prevalence of self-defined vegetarians was 2.74% in Study 1, and 5.97% in Study 2. Participants who were female, younger, and more educated were more likely to report following a vegetarian diet in both studies, and vegetarians had higher income as compared to meat eaters in Study 2. We also found differences between vegetarians and meat eaters with regard to personality traits, political attitudes, and health-related variables. Stepwise logistic regression analyses showed a unique effect beyond socio-demographic variables for openness (Studies 1 and 2), conscientiousness (Study 1), trust (Study 2), conservatism (Studies 1 and 2), and level of interest in politics (Study 1) on diet: Individuals with higher scores in openness and political interest had a higher probability of being vegetarian, whereas people with higher scores in conscientiousness and conservatism had a smaller likelihood of being vegetarian. We conclude that there are individual differences between vegetarians and meat eaters in socio-demographics, personality traits, and political attitudes.