WATER.
A healthy human being will spend most of his life in a calorie deficit i.e. you are trying to recoup the calories you lost. That makes juice good.
If you are concerned with calorie intake - and juice has plenty of calories, even when it's just pure, unsweetened, unadulterated juice - then just drink water. If water is too boring, then sparkling water, or coffee-flavoured water.
And do some exercise.
As Homer Stokes would say, IS YOU IS a lardass?
Water(tm)!!
Obligatory Powerthirst reference: