The dietary guidelines recommend that we try to choose meals or snacks

that are high in nutrients but lower in calories

to reduce the risk of chronic disease.

By this measure, the healthiest foods on the planet, the most nutrient dense,

are vegetables, containing the most nutrient bang for our caloric buck.

So what would happen if a population centered

their entire diet around vegetables?

They might end up living among the longest lives in the world.

Of course any time you hear about long-living populations

you have to make sure it's validated, as it may be hard to find

birth certificates from the 1890s.

But validation studies suggest that indeed they really do live that long.

The traditional diet in Okinawa is based

on vegetables, beans, and other plants.

I'm used to seeing the Okinawan diet represented like this,

the base being vegetables, beans, and grains,

but a substantial contribution from fish and other meat.

But a more accurate representation would be this,

if you look at their actual dietary intake.

We know what they were eating from the U.S. National Archives,

because the U.S. military ran Okinawa

until it was given back to Japan in 1972.

And if you look at the traditional diets of more than 2,000 Okinawans,

this is how it breaks down.

Only 1% of their diet was fish; less than 1% of their diet was meat,

and same with eggs and dairy.

So it was more than 96% plant-based,

and more than 90% whole food plant based—very few processed foods either.

And not just whole food plant-based, but most of their diet was vegetables,

and one vegetable in particular: sweet potatoes.

The Okinawan diet was centered around purple and orange sweet potatoes.

How delicious is that?

It could have been bitter gourd, or soursop?

But no, sweet potatoes.

So 90 plus percent whole food plant-based

makes it a highly anti-inflammatory diet,

makes it a highly antioxidant diet.

If you measure the level of oxidized fat within their system,

there is compelling evidence of less free radical damage.

Maybe they just genetically have better antioxidant enzymes or something?

No, their antioxidant enzyme activity is the same.

It's all the extra antioxidants that they're getting from their diet

that may be making the difference.

Most of their diet is vegetables!

So 8 to 12 times fewer heart disease deaths than the U.S.

You can see they ran out of room for the graph for our death rate.

Two to three times fewer colon cancer deaths,

seven times fewer prostate cancer deaths,

and five and a half times lower risk of dying from breast cancer.

Some of this protection may be because they were only eating

about 1800 calories a day, but they were actually eating a greater mass

of food, but the whole plant foods are just calorically dilute.

There's also a cultural norm not to stuff oneself.

The plant-based nature of the diet

may trump the caloric restriction though,

since the one population that lives even longer than the Okinawa Japanese

don't just eat a 98% meat-free diet, they eat 100% meat-free.

The Adventist vegetarians in California,

with perhaps the highest life expectancy of any formally described population.

Adventist vegetarian men and women live to be about 83 and 86,

comparable to Okinawan women, but better than Okinawan men.

The best of the best were Adventist vegetarians

who had healthy lifestyles, too, like being exercising nonsmokers,

87 and nearly 90, on average.

That's like 10 to 14 years longer than the general population.

Ten to 14 years extra years on this Earth from simple lifestyle choices.

And this is happening now, in modern times,

whereas Okinawan longevity is now a thing of the past.

Okinawa now hosts more than a dozen KFCs .

Their saturated fat tripled.

They went from eating essentially no cholesterol to a few Big Mac's worth,

tripled their sodium, and are now just as potassium deficient

as Americans, getting less than half

of the recommended minimum daily intake of 4700 mg a day.

In two generations, Okinawans have gone

from the leanest Japanese to the fattest.

As a consequence, there has been a resurgence of interest

from public health professionals

in getting Okinawans to eat the Okinawan diet, too.