Japan's light diet is related to its climate and natural environment. Commentary: Every June, Japan will start a new round of rainy season, which brings abundant water resources to Japan. Japan is an island country with a central uplift and undulating terrain. The rivers on the mountain flow to the Sea of Japan and the Pacific Ocean all the year round, and the water flows rapidly. Therefore, it is necessary to constantly replenish water sources and build reservoirs and dams to store water, otherwise it will affect agriculture and domestic water use. Abundant water resources provide unique conditions for Japan to grow rice and vegetables, which determines that Japanese people's eating habits are mainly rice and vegetables. In addition, Japan's natural drinking water is characterized by soft water, and the contents of minerals magnesium and calcium in soft water are less than 120 μ g/L. Because the water in Japan flows fast and the minerals in the surface rocks penetrate less, there is no peculiar smell. So Japanese soups are clear soups and don't need to be stewed for a long time. Instead, they extract umami from kelp or fish fillets and put some vegetables on them. The bottom is clear and the taste is mild. Even the miso soup of ordinary people is the same, but the taste is slightly heavier.