They will not literally die but they will not be healthy at all, many of them will likely live less than non-vegans. It is a dangerous lifestyle motivated by poor reasoning.
Okay, so not death. But other health issues? Can you point me to a relevant meta-analysis on PubMed or something? Because all I'm seeing from national dietetic organizations is support for the diet.
I'm not a vegan, if that's what you're asking: I'm vegetarian. But I assure you that vegans are not sickly due to protein deficiencies; they simply get it from other places.
