Vegan for humanitarian, environmental and health-reasons?

There is only one reason to be vegan and that is for the nonhuman animals. There are many ethical reasons to eat a plant-based diet. Surely we should expound on these reasons –e.g. humanitarian, environmental and health - but these are different moral issues.

Veganism is about justice for nonhuman animals. It is about living a life without exploiting, killing, and otherwise harming other animals as far as possible. It is not right to allow ourselves to adulterate this definition, so that veganism turns into a speciesist way of living that is all about or primarily about us humans – e.g. eating no or less animal products to alleviate starvation, reduce the environmental harm of our consumption habits, or improve overall Health