Through my experience of treating many patients as a physician, I have come to recognize the importance of disease prevention. About 30 to 40 years ago, my interest shifted toward research on nutrition and health. However, at that time, such studies were largely driven by agricultural and food scientists with little involvement from clinical physicians. Over time, a kind of “mutual invasion” emerged, and I began to study these disease-preventative foods from a new perspective. Today, interdisciplinary collaboration has become the norm, and the change is striking for someone who remembers the earlier days. Still, I am convinced that the direction we have taken is the right one and that research on functional food factors will continue to advance and be indispensable for public health.