Vegetarianism has gained more visibility in recent years. Despite the well-described effects of a vegetarian diet on health, its influence on the quality of life of the individuals who follow it still needs to be properly investigated. Quality of life relates to a subjective perception of well-being and functionality, and encompasses four main life domains: physical, psychological, social, and environmental. The adoption of a vegetarian diet, despite being a dietary pattern, could potentially influence and be influenced by all of these domains, either positively or negatively. This review aims to present an overview of the background, conceptualization, features, and potential effects of vegetarianism in all quality of life domains. The choice of adopting a vegetarian diet could have positive outcomes, such as better physical health, positive feelings related to the adoption of a morally correct attitude, an increased sense of belonging (to a vegetarian community), and lower environmental impact. Other factors, however, could have a negative impact on the quality of life of those choosing to abstain from meats or other animal products, especially when they go beyond one's control. These include the environment, the social/cultural group in which a person is inserted, gender-based differences, economic aspects, and a limited access to a wide variety of plant-based foods. It is important to understand all the effects of adopting a vegetarian diet-beyond its nutritional aspects. Not only do studies in this area provide more consistent data, but they may also contribute to mitigating all factors that might prevent individuals from adopting a vegetarian diet, or that may have a negative impact on the quality of life of those who already follow it.