(Newser) – Hitting "old age" doesn't mean what it used to: Writing in the Telegraph, Geraldine Bedell notes that almost 20% of people living in the UK right now will make it to the ripe old age of 100. So if we're living longer, when do we officially become old? According to some statisticians, we cross the magic threshold at 50—meaning a lot of us are going to be "old" for 50% of our lives. "You wouldn't think so, though, from the way that older consumers are ignored by marketing and advertising," writes Bedell. "Little wonder, then, that the over-50s exist in a kind of identity void ... on a downward spiral of invisibility."

The pundits are right: Great hordes of old people could destabilize society, but not just because they're going to cost a fortune: "They are going to force us to assess whether our current definition of the good life really adds up." Does it make sense "to cram all our economic activity into the first half of life? Why work our longest hours at a time when our children are young? Couldn't we take a longer view, one that would allow us to take gap years at any point, so as to take on voluntary work or go into further education?" Since we equate getting older with decline, it's no big shock that we want to believe 60 is the new 40. "It would be more helpful to think of it as the new 60." (Read more centenarians stories.)

