If you are going to drink juices, then you need to look for a few things:
~100% juice ONLY-no cocktails, punches, etc. because if you look closely, that means not all juice-but some sugar, water, corn syrup, etc.
~Drink juices with the most bang for the calories. Pomegranate juice, Acai juice, blueberry, cherry, orange, etc. have the most vitamins, antioxidants and nutrients in them-the cancer fighters, age fighters, heart benefits, and so forth.
The LEAST nutritious juice out there is apple juice. Most of the benefits from an apple are in the pulp and the skin, so the juice really is empty calories. For this reason, avoid it, and avoid JuicyJuice, the kids juice-even though it is 100% juice, because it is made "cheaper" for kids, by having 5-20% of Grape/Berry/whatever flavor it is supposed to be, and then the remaining is apple juice.
So, if you drink a juice blend, make sure that the blend is nutritious, and not a small amount of the good stuff filled out with apple juice. Read the ingredients list.
~Realize that a serving of fruit is one piece, or 1 cup of raw fruit, but a juice serving (by the food pyramid, diabetic diet exchange, and other plans) is only 1/2 cup, because of the calories. So if you drink an 8 oz. cup of acai juice, that counts as 2 fruit servings.
If you have any more questions, feel free to ask.