I grew up on a Vegan diet as a child thanks to mum's background and that is one of the many reasons I am still severely underweight and cannot thrive so yeah... I have seen some people achieve good health after going Vegan in their 30's or 50's so I do still recommend it to some people but I'm still not completely sold on the idea.
I'd like to see people raised Vegan (from birth as I was) turn out healthy and their children turn out healthy unlike me.
But if it works for some people even in the present moment then that's great. You just have to try everything out and see what works. Nutrition is not a straight-forward game.