yes, it slows the cleansing response, makes it all more bearable. I've read in Natural Hygiene lit where juice has been used just to conbtinue on, to get over some 'hump.
I wouldn't wantto be doing it much though--or it wouldn't actually be q water fast, and instead, would be a 'reducing diet.'
You might try an actual orange juice fast, at some point. I haven't done one, but they are said to be very pleasant--and to leave you with energy.