How the Okinawa diet could help you live to be 100

The Japanese island is deemed one of the world's five blue zones because of the long, healthy lifespan of its population

Umi-budo don, a traditional Okinawan seaweed dish, and dried asa-jiru seaweed. Getty Images

Our obsession with immortality may yet be fruitless, but what if there was a diet that not only kept us in good health, but also helps us live longer?

While no single food consumption pattern can take all the credit for increasing the lifespan of its followers, when a particular corner of the world churns out more 100-year-old people than anywhere else with unflinching regularity, it's worth wondering why.

The Japanese seem to have cracked the code. A 2012 United Nations report says the country has the highest concentration of centenarians in the world: 48 for every 100,000 people. That's more than twice the number in the UK and US, both of which stand at about 22 per 100,000.

Within Japan, the inhabitants of the prefecture island of Okinawa in the East China Sea, enjoy the longest and healthiest lives – with an average lifespan of 81 years, and with 40 per cent of Okinawans more likely to live to 100 than the average Japanese.

Focus on healthy carbs

Food scientists and medical anthropologists have been studying the traditional eating patterns of the island’s indigenous population for some time now.

In a nutshell, the Okinawa diet is low in calories, with high carbohydrates, low protein and restricted fats. It is largely plant-based, with a smattering of animal products – mostly seafood and a small amount of red meat, cooked in a way that skims off the fat to leave behind protein

"A diet is essential for creating an environment in the body that allows it to thrive, and the Okinawa diet, with its emphasis on whole, unprocessed and plant-based foods, decreases inflammation in the body. This allows cellular mechanism to function at the optimum level," says Dr Nicole Sirotin, chair of preventive medicine at Cleveland Clinic in Abu Dhabi.

Dubai dietitian Lima Fazaa says a contributing factor to Okinawan people's good health is that their diet lowers the risk of disease associated with age. This is because it's low in fat and calories, but rich in fibre and antioxidants. "The Okinawan culture also treats food as medicine and so the diet is rich in spices and herbs," she says.

In his 2015 book The Blue Zones Solution: Eating and Living Like the World's Healthiest People, Dan Buettner, a New York Times best-selling author, writes that Okinawans traditionally eat about seven portions of vegetables and two portions of grain a day, and fish two to three times a week. They obtain about 85 per cent of their calories from carbohydrates and fibre, nine per cent from proteins and six per cent from fats, with less than two per cent from saturated fats.

Fazza provides a word of caution, however. "High-carb diets have proven weight-loss benefits and are helpful in fighting inflammation, but only when the carbs you consume are high in fibre and come from vegetables, fruits and whole grains – not processed grains and sugar sources."

Ingredients in the Okinawa diet

The authentic Okinawa diet is crowded with bitter melons, shiitake mushrooms, purple sweet potatoes (at one time, the source of 60 to 70 per cent of the daily calories consumed by citizens), seaweed, taro roots, onions, a subtropical cucumber called hechima, Okinawa carrots and a green and purple leafy vegetable called handama.

Soy is the most popular legume in the region, consumed in sauces and in the form of tofu and miso. The most popular grains are brown rice, buckwheat (soba) noodles and seitan (wheat gluten). Meat consumption is limited, and takes in fish, squid, octopus and red meats. The abundance of herbs include turmeric, mugwort, jasmine tea and koregusu, a distilled liquor with chilli peppers.

Low calories key to long life?

In addition to eating a fresh, locally sourced, plant-based diet, the Okinawans are thought to practise mindful eating. The mantra "hara hachi bu" (eat until you are 80 per cent full), which many inhabitants recite before every meal, is a defining principle.

These islanders have been practising restricted calorie intake for more than 1,000 years, long before modern medicine started singing its praises. Studies show that a 20 to 30 per cent reduction in daily consumed calories leads to longer, healthier and more active lives in flies, worms, rats, mice and monkeys. It stands to reason, then, that it would have a similar effect on human beings, even after accounting for the impact of your genetic make-up.

Last month, a two-year study published in The Lancet Diabetes & Endocrinology journal said that cutting only 300 calories from your diet each day could significantly improve cardiovascular health – even if you are already at a healthy weight. The researchers found that participants who had restricted their calorie intake had lower blood pressure and cholesterol, and saw a 24 per cent drop in triglycerides fat levels in the blood. Participants also experienced a 10 per cent reduction in body weight, on average.

Eat to live

The result of a food tradition that combines non-processed, fresh foods with mindful eating is not only a longer life, but a remarkably healthy one as well. The ongoing Okinawa Centenarian Study, started in 1975, says that elderly Okinawans have the lowest frequency of the three major lifestyle killers – coronary heart disease, stroke and cancer – in the world.

The study found that the islanders are 80 per cent less likely to suffer from heart disease, 25 per cent less likely to have breast or prostate cancer and 50 per cent less likely to develop colon cancer or dementia, compared to people in the West. The research also claims that, on average, Okinawan citizens spend 97 per cent of their lives free of disabilities.

But here's the caveat: the Okinawa diet can be incredibly restrictive and difficult to follow for people outside the region. It allows for practically no dairy, and few fruits, nuts and seeds.

Many of us would be unwilling to trade in our wide variety of vegetables and legumes for a diet that leans heavily on sweet potatoes and soy. Also, most of the vegetables local to islanders aren't easily accessible elsewhere.

So how do you adopt the Okinawa way of eating? "It's definitely a harder diet to guide people into. We also have to consider the environmental consequences of the food we eat," says Dr Sirotin.

“What I try to do is help people think through the elements within the diet that they could adapt in their own environments. This includes: the foods they like and that are sustainably available; whole foods that are non-processed and plant-based; an increase in seafood; and elimination of refined grains and sugars as far as possible.”

Fazaa says the four Arabic foods that adopt the principles of the Okinawan diet best are: lentil soup, pea and carrot stew, pumpkin soup and bean stew.

Perhaps the one Okinawan tenet that's most easily adoptable is mindful or intuitive eating. Put simply by food consultant Lisa Harris, the answer is to tune in to the "age-old primal sense of knowing when we've had enough".