Intersting question!
I checked on syns on-line and 'non-branded carrot juice' comes up as 2 syns per 142ml and a branded beetroot juice is 2 syns per 100ml
Sorry, mate- I guess it is the same rule at fruit juice- that it is too easy to consume lots of calories in drink format as you don't really get the 'full-up' feeling you do from actually eating the stuff.
xxx