Weeeelllll... Really it depends whether fruit juice spikes your BG.
It would mine. But other people get away with it. I should try it and see.
The things I drink are approx (and highly variable)
Water
Soda streamed or sparkly water
Tea (have to be careful of the milk carbs)
Herb teas (simply can't face the high-stress competitive rat race of the milk buying rota at work)
Bovril & Chicken Bovril (rediscovered delights from my childhood)
Sambucol effervescent zinc and vit c tabs in water (1g carb per tab. Approx)
Natural fruit flavours, sugar free and artificial free, a couple of drops per litre (Aromhuset, from Amazon)
I don't count coffee because apparently it has a diuretic effect. But I do drink a largeish cup a day, with cream.
Hope that helps.