You've flipped the television station when someone walks in and you are watching some mind-numbing show. You've kept the book lying flat on your lap in the hope that no one will see the seductive cover. You've leaned over the weekly entertainment magazine when a person approaches you on the treadmill.

It's those little bits of entertainment that serve as junk food for your mind. They may not be necessarily hurting you, but they certainly aren't helping you.

As with food, it's best taken in moderation.

You can eat one chocolate-covered bon bon a day and still maintain your figure. Eat a whole box a day and you'll need a new wardrobe soon.

You can delve into mindless television shows occasionally and still hold an intelligent conversation. Make reality shows your only form of entertainment and you may begin to feel those I.Q. points drifting away.

Those romance novels with half-dressed people draped over each other splashed across the cover are not going to help anyone earn their PhD. On the other hand, not much thought is needed to breeze through the book.

With today's continuous news coverage, we can suffer from overload, which makes mindless entertainment even more necessary.

You may gain a valuable bit of information listening to news radio, but your mind breathes a sigh of relief when you tune to the all-'80s station. You may subscribe to Newsweek, but you still flip through the National Enquirer while waiting in the grocery check-out line.

There is a time and place for both intelligent entertainment as well as mindless entertainment.

For example, reading celebrity magazines can make the time fly, especially when you are exercising.

If you are using a stationary bike or any piece of exercise equipment with a screen to monitor your progress, the magazine can block all the stats, including the amount of time remaining on your workout.

During a recent workout on the bike, I found an old celebrity magazine. In the 15 minutes on the bike, I managed to "read" nearly the entire magazine. Rather than counting down the minutes until the workout was done, I pedaled on a few extra minutes to complete my daily "trash magazine" intake.

(And no offense to the 5:15 a.m. exercise class at the Y which can be entertaining, but the magazine makes the time pass a lot more quickly.)

Did I learn anything by the time I reached the end of the ride? Not really, unless you include the realization that no one looks good in a floor-length orange evening gown. But I was sweating and could have gone another 15 minutes easily if only I would have had another magazine.

Then there are the books which you read just for the sake of entertainment, just to put you to sleep at night, just to pass the time until dance lessons, basketball practice, swimming lessons, whatever are over.

Sure the books are fun to read at the time. But I have bookshelves lined with fiction novels that I vaguely remember reading, but couldn't tell you the plot, nor one single character. They passed the time, but didn't make any lasting impressions.

And as I flip open the cover and peruse the first couple of pages trying to refresh my memory, I'm quickly reminded that's usually a good thing when it comes those books.

-- Ronda Graff reads Newsweek on a regular basis, right after she finishes flipping through that week's People.