Livestrong claim that:
Sunflower, safflower, corn and soybean oils are polyunsaturated fats, also known as omega-6 fatty acids. These oils are bad for arthritis sufferers because they increase inflammation and prolong pain and stiffness, according to the University of Maryland Medical Center. Not all omega-6 oils are bad for arthritis, but these particular oils are. In lieu of these items, use olive oil. Many commercially baked goods like cookies and cakes contain these omega-6 oils.
I followed their link, but failed to see where the Uni of Maryland's Medical Center made such a claim.
Is there evidence that corn oil (or omega-6 fatty acids in general) may prolong pain and stiffness in arthritis sufferers?