It's funny to me how people talk about iron being a problem on a vegetarian diet. I've been a vegetarian for a decade or so now and my iron level is consistently at the very high end of the normal range. I don't do anything special to achieve this.
Same. I'm a vegetarian and I'm in perfect health. But if someone is extremely lethargic all the time, it's usually either iron, B12 or calories (rarely the latter). Also, some people become vegetarian and simply do it wrong. I know a girl who is vegetarian for icky reasons, ie she is disgusted by the idea of eating something's spleen/veins/anus, and it just stops her from eating any meat. But she's similarly icky about vegetables. Hates all kinds of things. She's low on iron, is constantly sick and lethargic.