Or when one decides to change their own life, with changes in habits, diet, and physical activity. Testing supplementation on themselves. Monitoring lab tests. This also greatly enhances the quality of their services.
Discussion
Yes, you are right. However, it's rare for regular doctors to do this for themselves without having a health issue first. Most doctors who study functional medicine and lifestyle medicine have had some health problem that led them to this field. I had one eight years ago and I still manage it naturally. It was after that that I changed my professional practice.