29.1.14

The Okinawa diet – could it help you live to 100? | Life and style | The Guardian

The Okinawa diet – could it help you live to 100? | Life and style | The Guardian



Can you eat your way to a century? I am not referring to test
cricketers, I'm talking about the Japanese diet. Or the Sardinian diet.
Or the Ikarian diet. Or any one of half a dozen regional, usually
traditional, ways of eating that have been credited with keeping an
improbable proportion of their populations alive beyond the age of 100.

Last week, the oldest man ever on record, Jiroemon Kimura, from Kyotango near Kyoto, passed away at the age of 116. His death, and the fact that the new record holder, 115-year-old Misao Okawa,
is from Osaka, reminded us that the Japanese know a trick or two when
it comes to living beyond 100. According to the UN they have the greatest proportion of centenarians in the world – and a great deal of that knowhow concerns diet.

I
have long taken an interest in how I might eat myself to old age. I
visited the southern Japanese Okinawa islands whose population is said
to include the largest proportion of centenarians in the country and met
with some of them in what is supposedly the village with the oldest
demographic in the world, Ogimi,
little more than a dirt street lined with small houses, home to more
than a dozen centenarians. Old folk tended vegetable patches or sat on
porches watching a funeral procession go by. My family and I dined on
rice and tofu, bamboo shoots, seaweed, pickles, small cubes of braised
pork belly and a little cake at the local "longevity cafe" beneath
flowering dragon fruit plants. Butterflies the size of dinner plates
fluttered by and my youngest son asked if there was a KFC.

The
next day I interviewed American gerontologist, Dr Craig Willcox, who has
spent many years investigating Okinawan longevity and co-wrote a book, The Okinawa Program, outlining his findings (recommending that we "Eat as low down the food chain as possible" long before Michael Pollan's similarly veg-centric entreaty).

Willcox
summarised the benefits of the local diet: "The Okinawans have a low
risk of arteriosclerosis and stomach cancer, a very low risk of
hormone-dependent cancers, such as breast and prostate cancer. They eat
three servings of fish a week, on average ... plenty of whole grains,
vegetables and soy products too, more tofu and more konbu seaweed than
anyone else in the world, as well as squid and octopus, which are rich
in taurine – that could lower cholesterol and blood pressure."

Okinawa's
indigenous vegetables were particularly interesting: their purple sweet
potatoes are rich in flavonoids, carotenoids, vitamin E and lycopene,
and the local bitter cucumbers, or "goya", have been shown to lower
blood sugar in diabetics. Like most of us, I am familiar with mainstream
dietary advice – eat less sugar, salt and saturated fat, cut down on the cronuts
and so on – but I much prefer the idea of discovering little-known
shortcuts to longevity; I'm more of a "silver bullet" kind of guy. With
this in mind, over a lunch of traditional goya chanpuru
– bitter cucumber, stir-fried with tofu, egg and pork – in a restaurant
that was little more than a tumbledown hut close to his campus, I asked
Willcox which elements of the Okinawan diet he had introduced to his
life. Turmeric and jasmine tea, he said; both potentially ward off
cancer. Needless to say, both now feature in my morning ritual.


Jiroemon Kimura

Jiroemon Kimura, from near Kyoto, lived to be the world's oldest man on record at 116. Photograph: Uncredited/AP


Of course, your destiny as a potential centenarian will also be
determined by your DNA, upbringing and temperament, as well as how
physically active and sociable you are; the climate where you live; the
standard of healthcare available; how relaxed you are about timekeeping;
whether you take naps and are religious;
wars, and so forth. Being born a girl helps: 85% of the world's
centenarians are female. But it is generally accepted that diet
determines around 30% of how long we live. Some argue it can add as much
as a decade to your life. So, the question then becomes, should we all
switch to a diet of tofu, sweet potatoes and squid?

According to Professor John Mather, a director of the Institute for Ageing
and Health at Newcastle University, it probably wouldn't do any harm
but the prevailing scientific evidence weighs more heavily in favour of
the Mediterranean diet. "There is not enough research on people who
adopt the Japanese diet in non-Japanese settings," he tells me. "It is
true Japan
holds the [longevity] record at the moment, but if you go back a little
it was Sweden or New Zealand." (The Chinese have referred to Okinawa as
the Land of the Immortals for centuries, but this probably does not
constitute strong epidemiological evidence.)

Mather, who has worked in nutrition
for 40 years, adds that the Nordic diet has made a late surge, with
recent research pointing to the benefits of its fish- and, more
controversially, dairy-rich diet (the latter is an anomaly in longevity
diets: the Japanese eat little dairy, and in the Mediterranean diet it
is mostly limited to cheese and yoghurt). But he still prefers to point
to the well-documented longevity of the people of the Nuoro province of
Sardinia or the Greek island of Ikaria, the latest destination on the
fountain-of-youth trail.

Last month this newspaper reported that one in three Ikarians make it past 90.
Among the dietary factors cited for their Methuselean tendencies are
herbal teas rich in antioxidants (including wild mint, good for
digestion, and artemisia for blood circulation), gallons of olive oil,
plenty of fresh vegetables and little meat or dairy. The US's
longest-lived community, the Seventh Day Adventists of Loma Linda,
California, also eat a largely vegetarian diet, and the people of Costa
Rica's Nicoya peninsula – another of the world's so-called "blue zones",
places identified by longevity researchers where people live to a
notably riper age – apparently eat large quantities of beans.

It
is surely no coincidence that Ikaria only got its first supermarket
three years ago, while, in contrast to the centenarians, the generation
of Okinawans born since the arrival of the US airbase and its
accompanying fast-food outlets have demonstrably declining health.


Mackerel

The Okinawans eat three servings of fish a week, on average. Photograph: Getty Images


"All of these diets work on similar mechanisms," Mather tells me.
"One hypothesis is that the secret about ageing is to avoid accumulating
molecular damage, and eating fish, beans, nuts, seeds, legumes, whole
grains, and not so much red meat, dairy or sugar may help us to reduce
that kind of cellular damage." Sadly, the professor is dismissive of
silver bullets: "In the early days we did try to link health with
specific foods or nutrients, but now we look more holistically at
dietary patterns."

According to some, those dietary patterns also
include calorie restriction (CR) – simply eating less, even of the good
stuff. Ikaria, Okinawa, Sardinia to an extent, and parts of Scandinavia,
have all suffered from periods of food shortage and their traditional
diets adapted to scarcity. Many now believe that reducing your daily
calorific intake from 10% to as much as 40% below the western average
can stall chronic diseases and boost immunity. Willcox advocated this
approach – indeed, the Okinawan dinner time mantra, "hara hachi bu",
means "eat until you are 8/10ths full" – but Mather is more sceptical.
"If you are a mouse, it's good news," he says. "If you are a human there
is really no good evidence about dietary restriction." In potentially
encouraging news for gluttons, he points out that recent large-scale
tests on rhesus monkeys have given conflicting results on CR: those at
the US's National Institute on Ageing were healthier but lived no longer
on a CR diet, while those at the Wisconsin National Primate Research
Center saw a survival rate improvement of 30%. CR societies, meanwhile,
point out that keeping monkeys in cages is unlikely to tell us anything
about human longevity.

So, what have the Guinness World Records'
oldest people eaten? Kimura recommended porridge, miso soup and
vegetables. His motto "eat light to live long" certainly chimes with CR
thinking. His successor as oldest person in the world, 115-year-old
Misao Okawa, reportedly celebrated her new title with her favourite dish
of mackerel sushi (an Osakan speciality, heavy on the vinegar). The
oldest person ever to have lived, Frenchwoman Jeanne Calment, who died
in 1997, aged 122, was a noted chocoholic who doused her dinner in olive
oil and drank red wine daily. The man the Russians once claimed as
their oldest, sawmill worker Magomed Labazanov, who died last year, aged
an undocumented 122, recommended wild garlic. Britain's oldest person,
113-year-old Grace Jones of Bermondsey, is quoted as preferring "good,
English food, never anything frozen" and enjoys a glass of sherry with
friends from time to time. And Britain's oldest man, 109-year-old Ralph
Tarrant smoked until he was 70 and likes a whisky. For the record, his
favourite meal is cottage pie.

I knew that there had to be a silver bullet somewhere.