Retarding the aging process would be therapy and enhancement because it would mean defeating diseases and because it would extend our life span.

When you extend life span, that's really something. That's hard to do.

The key to the future in an aging society is not found in increasing just our life span; we need to increase our health span at the same time.

In one century, we've added 28 years to our average life span - a change so rapid that our brains couldn't possibly have evolved to accommodate it.

It's possible that we could change a human gene and double our life span. I don't know if that's true, but we can't rule that out.

In the early '90s, we discovered mutations that could double the normal life span of worms.