A carbohydrate diet, high in fruits, vegetables and tubers, may be the key to longevity, at least by looking at the Okinawan population.
The Okinawa are a Japanese people known for their very low mortality and the absence of Western diseases typical of modern man. But today new studies focus on how many carbohydrates Okinawans consume compared to protein.

Well, the Okinawas have a real carbohydrate diet , with a consumption of carbohydrates ten times higher than that of proteins. A relationship very similar to the one that allowed a group of animals to increase their life expectancy according to a 2016 study.

But how do Okinawans go on a carbohydrate diet without gaining weight? 

The secret is that the glycemic load of their meals is low, precisely because the sources of these carbohydrates are natural and do not have many simple sugars. In short, these are complex carbohydrates, rich in fiber. 
Among these, sweet potatoes, bitter or karela melons ( you can find them here ), green leafy and yellow vegetables, other tubers such as bitter roots or at least rice noodles or rice. All of these carbohydrates are widely present at every meal, the percentage of fruit is reduced to two fruits per day, and the protein percentage is reduced to a little tofu, poultry and a little fish.
A miso soup is present for lunch or dinner.

If you want to deepen and discover the typical Okinawan carbohydrate diet, here is a detailed menu: the Okinawa diet.