Dr. John R. Christopher believed strongly in using your own fig tree or in plain words, using local herbs. He lived where citrus didn't grow, so he doesn't mention it.
I have mentioned orange to the Christopher family many times, their new version of their Dad's colon health book mentions oranges 3 differant places.
The use of oranges as a cure was amore a medical cure by a select group of doctors that didn't play the drug game.
My first 4 books of self-applied prevention study will all be orange juice cures.