All questions about Rheumatoid arthritis
What causes rheumatoid arthritis?
The immune system attacks the lining of the joints. What sets this off isn't known; genes, smoking and being a woman are among the risk factors.
Possible triggers people describe include a virus, an infection, an injury or a very stressful period, but nothing has been conclusively identified. Being overweight also raises the chance of developing it.
Sources
- NHS: Rheumatoid arthritis, causes
- National Rheumatoid Arthritis Society (NRAS): What is RA?
- Arthritis UK (formerly Versus Arthritis): Rheumatoid arthritis
- US National Institutes of Health (NIAMS): Rheumatoid arthritis
- World Health Organization: Rheumatoid arthritis, fact sheet
Reviewed 2026-11-09 · next review 2027-11-09