When I lived in my last place, my neighbor began making his own juices and got really into it. He was also working on a Ph. D in homeopathic medicine though. Online. He used to make this concoction of: Young celery Red grapes, with seeds Some lemon juice And some secret ingredients. Anyway, he swore it was good for cleansing the kidneys and several times, after heavy drinking, he had me try it. I don't know how true it is, but it did seem to help me get rid of a lot of stuff and generally, the next piss after that was pretty clear. The juice he made usually tasted a bit "earthy" (read: gross).
I love juicing and I tend to crave it. My favorite: Kale, romain lettuce, a whole lemon, two apples, ginger, celery, a beet and a handful of grapes. Nectar of the gods.