Fruit juice is not always what it seems to be.
The "so-called" fruit juices are often little more than water added with sugar and some kind of fruit concentrate. Frequently there is no real fruit inside!
But even if you drink 100% of real fruit it may still be a bad idea, just because fruit juices like orange juice have practically the same quantity of sugar as 4 muffins or any soft drink.
LIGUE JÁ