its not just the effect on ketosis or calories, but more about bloating and then causing some people to go on to crave other things...
Personally, if it aint in the book, it aint going in my mouth....but you need to accept that if you choose to have it, that it "might" have an effect on the diet/scales.
I've never been a coke person...so dont miss anything like that and i love my water....just make sure your having lots of water!
Maybe treat it the same as food....drink an extra couple of glasses of water before you give in to the need.....
hth hun
xxx