I love fruit and don't we all! But the amount of times I have had clients ask me, but isn't it bad to have too much fruit! Well yes your semi right anything taken in high quantities can be bad for you!
For example if you had four apples if you tried to eat them all you'd get to 2 and feel full. The fiber in fruit would tell your body you are full and you must stop, BUT if you were to juice the apples (4) you would be able to finish the drink BUT it would contain only sugar (16 tspn)
We are lucky nature produces this perfect packet full of nutrients,fiber, a little sugar to get the goods, but if we go and juice the fruit we only gain the sugar. So it depends in which way you are having the fruit, as a natural product it is fine, but once you mess with it you can easily have too much.