Sustainable Development (SD) is seen as an important task of today's societies. As sufficiency and sustainability play an important role for SD, it is also connected to nutrition. Different methods of nourishment are investigated on how they contribute to SD, for ecological reasons as well as reasons of (distributive) justice. Vegan and vegetarian diets are assumed to be more sustainable than many other diets. Nevertheless, most existing sustainability arguments for veg(etari)anism are purely anthropocentric and thereby ignore the ethical arguments for including nonhuman animals in the “moral community”. This paper will discuss convincing ethical arguments for including nonhuman animals in the discourse about SD. This argumentative diversification will bring up anthropocentric as well as sentientistic reasons for favouring a vegan diet for (among others) sustainability matters. Since nonhuman animals are not included in the SD discourse yet, such an inclusion will bring a completely new dimension into this discourse.
