There is no single research paper on the drinking water. It is based on the fact that water is the best detox for the body (and several other things) and I've practiced it since I was a kid. Each persons bodies are different but I can tell you that I've never faced any nutritional problems and I've never had to spend a night in a hospital.
Minerals could get washed away with other toxins. A good organic diet should take care of this. I do eat a decent amount of greens regularly.