In modern society, Japan has become the world’s longest-living country, but the number of bedridden and dementia-afflicted elderly is increasing, and the reality is that it cannot be called a country of long and healthy life expectancies. What does Japan need today to fundamentally solve these health issues? As a gastroenterological surgeon, I have pondered this question while facing cancer patients and their families every day. In my search for an answer, I have focused on the need to “improve health while you are still healthy,” rather than “treat when you become ill,” and I believe that this is what is important for modern Japan.