All questions about ME/CFS and long COVID

Is ME/CFS a real illness?

Yes. It's a recognised long-term condition, described by health services and covered by clinical guidelines.

Its cause is still being investigated, and there's no single test, which is why people with it are often doubted. Feeling doubted is linked to worse health.

Sources

• NHS: Myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS), overview
• ME Association: What are ME/CFS and long COVID? (summarises the NICE 2021 guideline)
• Kool et al.: Social support and invalidation by others contribute uniquely to the understanding of physical and mental health of patients with rheumatic diseases (Journal of Health Psychology)
• NHS: ME/CFS, diagnosis

Reviewed 2026-11-09 · next review 2027-11-09