Dairy
One of the foods to avoid with arthritis are dairy products. Rheumatoid arthritis can specifically flare up in response to the proteins found in dairy. Some people with RA are actually intolerant to proteins found in milk; their bodies form antibodies to milk proteins, and attack those proteins when they’re found in the body, according to the Physicians Committee for Responsible Medicine.
But not everyone reacts the same way to milk—or to other various types of dairy. In a 2015 study of women with osteoarthritis, milk improved knee pain but cheese made it worse. Experiment to see how foods tend to affect your particular type of arthritis.