JOHN YANG: A lot of people do a lot of things in search of a long and healthy life, complicated diet plans, gym memberships and expensive dietary supplements.

But in a four-part Netflix series called Live to 100 Secrets of the Blue Zone, Best Selling Author Dan Buettner says a lot of that is misguided.

He traveled to places he calls blue zones where more people live significantly longer than average, trying to figure out how they do it.

Recently, I spoke with Buettner and asked him why he chose to start a series on longevity in a cemetery.

DAN BUETTNER, Executive Director, "Live to 100: Secrets of the Blue Zones": I think it's facing the inevitable, we're all going to get frail.

We're all going to die.

But when we -- how long we want to be on this earth, we have a lot of say in that matter.

So we started at the end, and then went back from there.

JOHN YANG: When you found these blue zones, where there's some themes running through all of them?

DAN BUETTNER: Yes, if you want to know what 100-year-old ate to live to be 100, you have to know what she was eating as a child and middle aged and newly retired.

So to get at that, we found 155 dietary surveys done in all five Blue Zones over the last 80 years.

And we average them with the help of Harvard.

And we found that 90 to 95 percent they're eating a whole food plant based diet, meat only about five times per month and contrary to a lot of sort of keto slash Paleo diet advice, it's mostly carbohydrates, complex carbohydrates, which I think shocks a lot of people.

When I first started writing about this, I did a cover story for National Geographic in 2005.

Nobody was connecting loneliness to longevity.

And I was pointing out the importance of strong social connections and social circles and turns out that's worth about seven years of extra life expectancy.

But the big revelation and you'd never hear about it because it's not saying exceed marketers can't sell you things but like an extra 10 years of life expectancy is the sum of lots of small improvements we make in our lives mostly in our environment, applied for decades.

JOHN YANG: Are these blue zones in any way endangered you talk about Okinawa now having an obesity problem that family in Costa Rica with a young boy just want cereal?

Are these endangered locations?

DAN BUETTNER: As soon as the American food culture comes in the front door, longevity goes out the back door.

And I'm giving most of these blue zones a half a generation before they completely adopt our way of life and therefore started adopting our obesity rates and diabetes and heart disease rates to tragedy actually.

JOHN YANG: But at the same time, he also tried to create some blue zones in Albert Lee, Minnesota and Fort Worth, Texas.

What lessons did you learn from that?

DAN BUETTNER: The big lesson is don't try to change your behavior you'll fail for almost all the people almost all the time in the long run.

You change people's environments.

In other words, you design for health.

Our Blue Zone projects unleash a swarm of healthy nudges and defaults that are put in place for years.

They're mostly environmental, making cities walkable policies that favor healthy food over junk food and so forth.

And setting Americans up for success, as opposed to the failure our food environment portends right now.

Every city we work in, we've seen major improvements in people's health.

And we've seen obesity drop, and we've seen health care cost savings in the in the hundreds of millions of dollars.

JOHN YANG: So it sounds like it's not just personal behavior.

But it's also as you say policies making cities more walkable, designing, you know, streets and neighborhoods like that.

DAN BUETTNER: I have no faith.

And I don't know of any research where you can change a populations health by trying to convince individuals to change their behavior, or somehow imbue them with responsibility.

We're genetically hardwired to crave fat, salt and sugar and take rest whenever we want.

So unless we set up an environment where it's easy for us to eat, basically whole food plant based, easier for us to walk than it is to drive.

We're going to continue to see health care costs in the trillions as we're seeing today in America.

JOHN YANG: You talked also about in the series about something we've talked about on this broadcast the fact that life expectancy is becoming shorter.

And a lot of it is because younger people are dying from suicides, homicides, drug overdoses and car accidents.

All preventable.

There's none of this as is an organic problem.

Did you learn anything in your work?

That would relate to that?

DAN BUETTNER: The number one killer in America is our diet.

We lose about 660,000 Americans prematurely to the way we eat.

If we don't take aim at that, these other things are more peripheral.

In Singapore, which I dubbed ouzo 2.0, individuals cannot own guns.

In America, we lost 55,000 people to gun deaths last year that dragged down the life expectancy.

in Singapore they lost two, where they're very tough on drugs in Singapore, I mean, if you could be put to death for selling drugs in Singapore.

But the other side of that equation, only 15 people died last year and drug overdoses, whereas we lost almost 110,000 Americans and drug overdoses last year of drug related deaths.

So yes, there are lots of things on the fringes.

But the big thing we need to take aim at is our diet.

And until we get that squared away, the rest of the stuff is a rounding error.

JOHN YANG: Toward the end of the series, you see the same things that help us live a long healthy life are the things that make life worth living.

Are you saying that if we concentrate on the quality of life, that the quantity of life will come?

DAN BUETTNER: The concentrating on quality of life helps, but these silicone multimillionaires shooting themselves up with a young people's blood, and working out six hours a day and taking all these weird pills and genetic interventions.

People in Blue Zones are living a long time because they're socializing, because they know their purpose.

And they live their pure purpose.

They live near nature.

They keep their families close by and we can map all these to higher life expectancy.

So the big point for Blue Zones is if you adopt the Blue Zones way of life, you not only stack the deck in favor of longevity, but you can be pretty sure that journey is going to be pleasurable.

JOHN YANG: Did you change anything in your life based on what you learned?

DAN BUETTNER: Yes, I become mostly plant based.

I don't eat meat anymore.

I used to be a ultra-marathon cyclist and now I do things like play pickleball and take walks because I know that favors my longevity more than hardcore physical activity.

I got very clear on my purpose.

It's very hard to get me to do things that are right down to the strike laying up my values and what I'm good at and what I like to do and how I can give back.

And I've also prioritize family because I know keeping your family nearby adds three or four years of life expectancy over being single and alone.

JOHN YANG: The series is Live to 100 Secrets of the Blue Zones.

Dan Buettner is the host and one of the executive producers.

Thank you very much.

DAN BUETTNER: We'll see you when you're 100, John.

JOHN YANG: It's a deal, all right.