Comment by mstroeck

ME/CFS is an under-researched, multi-system disease that affects people in a multitude of ways and is very hard to diagnose. There are no accepted bio-markers yet. There are, however, many well-respected researchers in the field, and more are beginning to enter it from all kinds of disciplines. Basically none of them think this is a psychosomatic illness. This is a good place to start for getting an overview of interesting current research: https://www.omf.ngo/the-end-mecfs-project-2/