Poker when to call the odds...?

In a tourney I have 1,000. I put in 100 and guy goes all in for 600. I am getting the odds to call but it's for half my stack. Let's say I am trying the odds but im thhe slight underdog... Since I have to call with half my stack is it good/ standard(ish) to fold as i can't afford this because .. ( this next bit I'm uncertain about ); if I call in the long term I will lose as it's to expensive for my stack....?