I can vouch for this information regarding the tooth enamel as I experienced enamel loss on a 21 day orange fast. It's a small hole that ate through the top of a back molar, still there (3 years since), and occasionally a poppy seed might get stuck and I have to pop it out haha. During the fast I also juiced pineapple a few times and drank coconut water as well as plenty of distilled water. I don't regret taking the cleanse, but it would have been nice to have had this information. Most orange sources I read up on did not mention this at all. I recall in my acid/alkaline book that the acid is carbon based and so is released through the lungs and not through the kidneys, but nothing on the tooth enamel. Needless to say, it's true.