I wouldn't suggest an internet diet to anyone over 15 years of age. Brains feed on information and the information on the internet is vastly more interesting than what most people encounter in an everyday "offline" life. Seems like the problem is the distractions caused by social sites. It's easy to turn that habit off, you are not missing much anyway. If you feel you are feeding too much on web fragments, read some books on a kindle for a break.
You know how in the old days people used to travel to experience something new?
This is similar.
Also there's the idea that we get really good ideas when we have time to process the information we have collected. And I do in fact use this to great advantage when developing algorithms. Learn about a problem, then just go do something else.
Let's say for the past few years I've been cramming information into my head, now I'm taking a break to see if I can't come up with some insight.
"You know how in the old days people used to travel to experience something new?"
What do you mean "in the old days"? From what I can see people are still travelling a hell of a lot to "experience something new" and this is often facilitated by the Internet. And it's hardly an age thing - most people I know in their 20s seem to be very keen on travelling.
In the olden days, people painstakingly traveled to foreign lands in order to collect information which is now instantly available. Traveling is mostly leisure/adventure nowadays. I 'm not saying that it's good to be on the internet all the time, just that the internet is not the problem.
The problem is that too much stuff on the Web is pre-digested pap. In terms of what Stephenson wrote in In the Beginning Was the Command Line..., it is turning Morlocks into Eloi.
