Stop consuming sugar and caffeine. Fruits are a great suppliment until your body adjusts. You cannot have an abundance of attention without the fuel to power it. - It was one of the hardest things for me to do.
And if you do want to go by research, please read the works and watch videos of "Robert Lustig" (http://profiles.ucsf.edu/robert.lustig )
Like plutonium?
The difference is, that fruit tends to contain a lot of fiber, which makes the fructose harder and slower to absorb. So fruit is okayish.
However, fruit juice is just sugar water worse for you than Coke, so keep that in mind.
It's when you refine the fruit (e.g. juice it) that you separate the fiber away and therefore loose the counterbalance. The fiber and relative inconvenience in consuming the fruit also help to regulate the intake. Contrast a tall glass of orange juice, which is about 4-5 oranges minus their fiber, with manually pealing and eating that same number of oranges. One can be gulped under a minute, or maybe a few minutes if you drink it slowly, the other will take quite a while to eat and leave you with a feeling of being full.
That's why if I'm offered juice, I try to sip it slowly.