My sims never die from old age. They're Immortal.

The age bar on the younger sims progresses. The elders bar just flashes and doesn't even say how old they are.

I read an article tho, that stated it might be down to the long lived trait http://forums.thesims.com/en_US/discussion/788031/how-does-the-long-lived-trait-work

I might have to keep waiting it out....but they are SERIOUSLY long lived if this is the case