Rheumatoid arthritis (RA) is an autoimmune condition that causes inflammation of the joints when the immune system attacks protective tissue, which leads to pain, swelling, and potential joint destruction. Unlike osteoarthritis, RA results in a distinct type of "squishy" joint swelling rather than the hard, bony enlargements that are typical of osteoarthritis.

Rheumatoid arthritis primarily causes pain and swelling in the joints, particularly in the hands, feet, and knees, and often worsens in the mornings and improves with movement. Additional symptoms may include red puffy hands, fatigue, loss of appetite, fever, and the presence of rheumatoid nodules under the skin.

Rheumatoid arthritis is diagnosed through a combination of medical history, physical exams, X-rays, and lab tests that assess inflammation and autoimmunity. Key diagnostic tests include the ANA test, CRP test, CCP antibody test, complement blood test, ESR test, RF test, and synovial fluid analysis.

Rheumatoid arthritis has no cure, but effective treatments aim to relieve pain, reduce inflammation, and suppress immune activity to prevent further joint damage. Common treatments include nonsteroidal anti-inflammatory drugs and steroids, which are often used alongside immune-suppressing therapies and are initiated promptly after diagnosis to limit disease progression.

Several supplements have shown promise for relieving rheumatoid arthritis symptoms, including omega-3 fatty acids, gamma-linolenic acid (GLA), thunder god vine, and probiotics.

The relationship between diet and rheumatoid arthritis (RA) is not well understood, although there is a connection between diet and the immune system. People with RA should consult their physician before starting any special diet because the effects of specific diets on RA symptoms are still a topic of ongoing research.

Various treatments have been studied for relieving rheumatoid arthritis symptoms, including acupuncture, massage, mindfulness meditation, tai chi, yoga, Ayurvedic medicine, and balneotherapy. These alternative therapies may provide additional options for managing the condition.

Rheumatoid arthritis is caused by the immune system mistakenly attacking the body's own tissues, particularly the synovial lining of joints, which leads to inflammation and joint damage. Although both genetic and environmental factors contribute to the disease, the exact mechanisms behind this autoimmune response remain unclear.