I used to drink a lot of fruit juice. In fact...I thought juicing was one of the healthiest things a person could do...until I became educated. Now I know better. When you make juice you lose almost all the fiber. Fiber is the non-digestible part of a plant...it is really good for you...which is why people buy fiber pills, and foods advertise how much fiber their product contains.
Fiber binds the fruit sugar molecules together, so when you eat the fruit...the sugar gets released into your system slowly. Fiber also acts like a rotor rooter on the walls of your intestines. It helps to clean them by binding poisons and waste products, then passing them through.
When you juice you lose all the fiber and the sugar goes right into your system...elevating your insulin levels, just like a Coke or a candy bar.
Elevated insulin levels can cause rapid weight gain and contribute to diabetes. This is one of the reasons so many kids (and adults) are obese. It's not like this is new cutting edge information either...but it's stuff most folks just don't know.
Anyway, this months Dr. McDougall newsletter has a really good article entitled: