Source: Br J Nutr. 2014 Nov; 112(10)

Motivations guide real-world dietary choices and lead to different health consequences. We all know that not all vegetarians are alike: there are vegans, lacto-ovo-vegetarians, pesco-vegetarians, and so-called flexitarians. They may have different primary motivations for being vegetarian, including ethical, health, ecological, or religious concerns. But only some vegetarian patterns are associated with reduced consumption of added fats, sweets, snack foods, and refined grains; cultural motivations are still influential in dietary choice. An example would be a vegetarian whose primary motivation is to decrease animal suffering. This hypothetical person will consume more plant foods and less meat than a non-vegetarian but may not avoid soft drinks and snacks that contain added fats, sweets, and refined grains. When evaluating scientific information about the health effects of vegetarian diets, we should keep the motivations of the study population in mind. While all vegetarians will avoid the consumption of meat, their motivation for doing so influences their choice of foods, which in turn influences the nutritional consequences of their diet.