Calling it "Third World Diet" incredibly offensive. People who live in third-world countries are hardly vegan. Their starving because rich countries like ours have trade agreements, propell the small arms black markets and prolong wars that their economies wouldn't normally sustain, and because we're too busy wasting money on fast food, technology, and warfare.
Then again, there are plenty of people living in third world conditions in North America too.
I really think you should be dubious of this diet if its called that.
Regarding Veganism,protein and iron can be more difficult to maintain. I have a great vegan cookbook called 'Vegan Planet' that explores all that, what to stock your cupboards with, etc. It's not a weight loss book, it's a sustainable living book
A place to start.