Can I be vegan for the sake of saving animals from suffering?

The Prophet (PBUH) warned us about making haraam (forbidden) for ourselves what Allah had made halal.  So, yes, you can be vegan for any personal or health-related belief you have, so long as you do not believe that eating meat is haraam.  Further, the Prophet (PBUH) reminded us that we will be held to account on the Day of Judgement as to how well we took care of our bodies.  As such, those who engage in a vegan diet are reminded to seek medical counsel to ensure their bodies are sufficiently nourished, including the necessary amino acid normally found in animal-based protein.