Okinawa is another hotbed of centenarians that Dan Buettner studied and interviewed for his book, The Blue Zones. Called the Japanese Hawaii by him, the centenarian ratio according to him is 5 people over 100 for every 5000 people.
Unfortunately, that is changing rapidly as mostly the men under 50 embrace the Western culture and fast food. In fact, the favorite dish in Okinawa as of the writing of the book is a SPAM and vegetable stir fry. It’s not like it used to be.
In two different trips, Buettner interviewed different centenarians to gather material on why they lived so long. In 2005 he went back for his story for National Geographic and this chapter on the Okinawa Blue Zone is based on the interviews and surveys he did.
Before going into some detail about what he found, you need to know this. Toward the end of his trip, Buettner talked with Dr. Nobuyoshi Hirose who is one of the foremost Japanese centenarian researchers who at the time of the book had been studying centenarians for 15 years. When asked why the population of people over 100 had ballooned over the last 40 years, he told Buettner that, “The only common factor we could find is the heterogeneity of centenarians.” Basically, they don’t have much in common but whatever they are doing makes them live longer.
But there were several things that could be drawn from Buettner’s Blue Zones trip to Okinawa. At the end of the chapter on Okinawa, the author lists several things we can take from what he learned to apply to our own lives to hopefully make us live longer.
What Okinawan Centenarians Eat
Basically, they eat lots of vegetables grown in their own gardens. Unlike the northern islands of Japan, Okinawa is placed geographically such that the inhabitants can grow their own food all year long. This means among other things that they do not have to rely on pickled and preserved foods which would increase their salt intake. This is one item some of the scientists think help with their longevity.
However, the soil is poor and rocky meaning that a basic subset of vegetables can be grown and these vegetables are what make up most of the meals. These vegetables include daikon, bitter melon (goya), garlic, onions, peppers, tomatoes, sweet potatoes (imo) and various herbs including mugwort and turmeric. (A couple of these I wonder how they grow as the plants are heavy feeders.)
In addition to their vegetables and herbs, they eat tofu almost daily. The tofu in Okinawa is higher in protein and good fat than even the Japanese or Chinese versions. Additionally they use miso for making their soups.
As for meat, they eat very little. While some use a little fish now and then, the other main meat is pork. Every lunar New Year the family pig is butchered and then slow cooked at a low temperature with the fat skimmed off and made into a kind of stew.
Lastly they drink green tea and herb teas. Lots and lots of green tea is consumed all day long.
Going back to one vegetable above we need to take a quick look at history as this plays an important part later on in this article. The Okinawan people were peasants throughout most of their years subject to conquest by both Japan and China. They lived mostly off the land as one would assume where there was little in the way of any kind of industry.
Remember when we mentioned how poor and rocky the soil is which makes it hard to grow vegetables. Well, weather also plays a big part. Typhoons would come in and wipe out the gardens. The people would then have very little to eat. In 1605, a man brought in the imo, or sweet potato, from mainland China. He is hailed as a hero and even has a statue. Imo was able to grow quite well in the soil and was able to survive the typhoons as well making it the center piece of the Okinawan diet. By the early 1900s when many of the centenarians Buettner interviewed were born, 80% of the calories Okinawans ate came from imo. People ate it morning, noon and night.
In fact, one woman when asked if she still ate imo now, said she had eaten it every meal for her first 50 years and was tired of it. Although sweet potatoes have lots of good nutrients and vitamins, that is a very limited diet for anyone.
So how is eating imo a secret to living longer? Later on in this article we will cover that.
Hara Hachi Bu
What does hara hachi bu mean? Quite simply it is a reminder to eat only until you are 80% full. Most Okinawans say this before every meal as was shown by at least two women the author interviewed for his book. In fact, I read about this previously on the Zen Habits blog.
This means Okinawans used to eat fewer calories through the day than Americans who eat till they are full or past full. As most Okinawa people are generally smaller than Americans this really goes a long way toward limiting their caloric intake. Being smaller, of course, they don’t need as much either. With the changes that prosperity has brought to Okinawa and what the men are eating, I doubt younger generations are still saying this for the most part.