The aim of this paper is to examine the factors associated with the belief that vegetarian diets provide health benefits. A random population mail survey about food choice was conducted among a sample of 1000 South Australians. An additional (non-random) survey of 106 vegetarians and semi-vegetarians was also conducted, giving a total of 707 participants from both samples. The main predictors of the belief that vegetarian diets provide health benefits for all respondents were found to be the belief that meat is neither healthy nor necessary and frequent searching for information on healthy eating. However, there were differences between vegetarians, non-vegetarians and semi-vegetarians. In particular, health issues were relatively more important for semi-vegetarians and vegetarians, while knowledge and convenience issues were most important for non-vegetarians. The results have important implications for public health. Many South Australians perceive that health benefits are associated with eating a vegetarian diet, which may also apply to plant-based diets in general. However, if non-vegetarians are to obtain some of the health benefits associated with the consumption of a plant-based diet, they require information on the preparation of quick and easy plant- based meals.