If you read my reply, one of the biggest problems is that it makes the intestinal pH more acidic, which is hostile to many of the friendly bacteria that live there.
However, those bacteria are very interactive with both our metabolism, our immune system, and other microorganisms.
The fear of pH "imbalance" in the human body is also way overblown. The pH of fluids both inside and outside cells remain nearly constant despite adding to, or the body's manufacturing of strong acids and/or bases. This amazing physiological phenomenon is known as the buffer system and easily deals with most acid/base challenges we throw at our bodies.
Even so, there are a whole lotta people eager to sell you the newest magical cure for pH imbalance that is backed up by numerous studies designed to deliver the desired outcome:Fear.