PsA causes swelling. So do certain foods, like fatty red meats, dairy, refined sugars, processed foods, and vegetables like potatoes, tomatoes, and eggplants. Avoid them and choose fish, like mackerel, tuna, and salmon, which have omega-3 fatty acids. Those have been shown to reduce inflammation.
Jump to: General Information Good Foods Diet Triggers Psoriatic Arthritis Diets. What should you eat to decrease inflammation?. Apple cider vinegar: a great natural agent to reduce psoriasis flare–ups, especially scalp psoriasis. Fish oil: .