What’s the secret to eternal youth? To be honest, the jury is still out on that one, but if there’s one country that might be able to give us a clue to then it’s surely Japan, which boasts the world’s longest life expectancy, clocking in an impressive 81 years for men and an even more impressive 87 for women. Even further ahead of this, however, is the Japanese prefecture of Okinawa, a group of islands affectionately dubbed “the land of the immortals,” so called because they're home to a higher number of centenarians than anywhere else on the planet.
So, why is this? Well, according to scientists, it could be – at least in part – to do with dietary choices.
What foods does the Okinawa diet consist of?
Time and time again we hear that the Mediterranean diet – one high in fruit and veg, healthy fats and wholegrain starches such as pasta – is the most beneficial to health, and the Okinawa diet isn’t actually a million miles away in terms of its nutritional scope, being low in saturated fat and high in antioxidants, with a low glycaemic load.
So, what’s the difference? On a day-to-day basis the Okinawa diet consists primarily of starchy root vegetables, yellow and leafy green vegetables, bitter melon, multiple servings of fish per week and the frequent use of soy-based products such as tofu. The jewel in the edible crown is its heavy use of vitamin-rich purple sweet potato – a food that has been credited with being a powerful antioxidant, reducing inflammation (1) and offering resistance against age-related diseases (2).
What are the benefits of the Okinawa diet?
According to studies, the Okinawa diet is still lower in fat than other comparable diets and this, in combination with factors such being naturally low-calorie but high in fibre and antioxidants, can help to ward off dietary-related health conditions. In fact, scientists have gone so far as to say that the foods comprised in the Okinawa diet "are likely contributing to a decreased risk for cardiovascular disease, some cancers, and other chronic diseases through multiple mechanisms, including reduced oxidative stress” (3) within Okinawa's population.
Are there any pitfalls?
As with any style of nutrition, there are some limitations. Most studies, for example, do point out that this diet is traditionally also paired with a high level of physical activity, as a result of the prevelance of manual work in this area. As you're probably aware by now, this lifestyle trait is also crucial to warding off ailments such as cardiovascular disease and dementia (4), and so the diet of Okinawa may not be exclusively responsible for the longevity of those living there.
That said, as healthy diets go, it seems like a fairly good foundation.
4. Helena Hörder, Lena Johansson, XinXin Guo, Gunnar Grimby, Silke Kern, Svante Östling, Ingmar Skoog. "Midlife cardiovascular fitness and dementia." Neurology Apr 2018, 90 (15) e1298-e1305.