Alongside his clinical practice, Yan served as a senior researcher at the Sino-Dutch Centre for Preventive and Personalized Medicine, a research group within TNO, and as scientific director of the Boann Systemic Research Group. He publishes regularly in professional journals and gives lectures, courses and workshops in the fields of systems theory, systems biology and classical Chinese medicine.

In his teaching he weaves together systems biology, quantum theory, Taoism and Chinese medicine into a single coherent whole, in which Eastern and Western ways of seeing illuminate one another. As a guest lecturer he is affiliated with various national and international training programs, and he speaks at conferences around the world.