This is NPR's Life Kit.

I'm Andy Tegel, one of the producers of this show.

If I asked you to picture an older person,

what are the first few things that come to mind?

Is it wrinkles and gray hair?

Do you see a kyle grandma with thick glasses fumbling with technology?

Or maybe a cranky uncle taking his daily pills in the kitchen,

yelling at you kids to keep it down?

These stereotypes of aging and older people might feel standard,

a given. An eventuality you can expect once you hit, say, 65.

There's no biological measure of aging.

We're not like trees that have number rings that we can count that is a biological measure of aging.

And there are many different things that go into it, including how culture defines aging

and how we ourselves define our own aging.

So there really isn't one set age that determines older adults in our country or in the world,

but I think in most studies, it's around age 60, 65 that people start to enroll in studies that

are looking at aging health.

That's Beca-Levy, a professor and researcher at the Yale School of Public Health,

a founder of the Age Liberation Movement, and author of the book, Breaking the Age Code.

How your beliefs about aging determine how long and well you live.

She says the US in particular has a big problem with ageism, but we're not the only ones.

According to the World Health Organization, ageism is an extremely pervasive and socially accepted prejudice.

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