How can I stop a Java while loop from eating >50% of my CPU?

Okay, I tested this on an empty program, and just having a while(true){} running gave me >50% on my CPU. I have a game I'm working on that uses a while loop as it's main loop, and it's CPU is at 100 all the time.

How can I get Java to repeat something over and over without eating up >50% of my CPU just to do the repeating?