What can alter your ra factor?

RA factor is a screening test, not for diagnostic purpose. The falsely positive rate, i.e. positive Rh factor but no rheumatoid arthritis, is much, much higher than the falsely negative rate, i.e. rheumatoid arthritis is confirmed but rheumatoid factor is negative. Many patients with chronic illnesses which include cancer and chronic infections and autoimmune diseases have falsely + Rh factor.

Nothing and you don't need to alter it. Even if you have rheumatoid arthritis (many people with a positive rheumatoid factor don't have RA), the amount of positivity does not correlate with rheumatoid disease activity. People have positive RF due to heredity, rheumatoid arthritis, Sjögren syndrome, hepatitis, chronic infections ... the list goes on. Some people have a positive RF with no cause.