What you said is mainly that Japan belongs to an island country, and the mineral resources are not too rich, especially the fruit is scarce. At this time, it mainly fishes in the sea, and all the fish it eats belong to marine fish, which is particularly low in fat. Moreover, after people eat it, the unsaturated fatty acids corresponding to the human body still have some regulating effects on the body, so there is little fat inside, so people are not easy to increase obesity at this time. In addition, the sea area is rich in trace elements, which are generally safer than things on land. So generally speaking, Japanese people eat more marine fish, so they are still healthy.