The book says to have OJ for the first day after day 10 but doesn't say how much. It also doesn't say anything about any other substance? For those who have been there before, did you really only have OJ for the whole day? How much? Isn't all the acid a bit harsh?
If you water the juice down, anywhere up to half juice/half wataer, you can have as much as you want. The acid content is no different than all that lemon juice you've been ingesting. Drink up and enjoy! You get soup tomorrow.
That's a good reminder about watering it down. It is really too much too soon if you drink it straight. I love to drink OJ juice with a LOT of crushed ice so that the ice melts really quickly and dilutes the OJ, I can also eat some of the ice.