Also if you make sure to drink most of your juices alongside a meal, the addition of proteins and fats will slow absortion for you.
If you think about it, let's say you drink 300 cals a day of juice. if you're eating 2500 - 3000 cals a day that's only 10%-12% of your daily intake, and you're getting antioxidants and hydration out of it. *imitates alton brown's analytical voice tone* 'Poly-phe-nols'.