In addition to this, it's worth noting that not all calories are created equally. If you process your food to make juices, smoothies etc (or buy it already processed), then you'll get a greater, more immediate hit of energy than if your body broke it down itself.

http://blogs.scientificamerican.com/guest-blog/2012/08/27/th...

But you also end up getting all of the fructose and none of the fiber, which your body needs for processing the fruit without the sugar hit. Lustig: "When god made the poison, he packaged it with the antidote."