how best to use a DS1307

I've got a DS1307 on my breadboard, and I'm currently (I think) polling it for information the whole time the Arduino is powered on.

The following bit of code features in my loop DateTime now = RTC.now(); and the chip is powered from 5v, not an I/O pin.

Am I correct in thinking this is going to wear the battery down and I should instead be updating the Arduino's built in time capability and letting the DS1307 have some shut eye?

Or is this, in fact, fine?

It only uses the battery when there is no power being supplied, so if you have it attached to the 5v supply you'll be fine.