This from an Artice on foods to eat and foods to avoid if you have Arthrtis, its a start to avoiding all vegetable oils.  The first part of the article focussed on, well, Zone fav foods that supply:  Omega 3's, Vitamin D, Vitamin C, & Selenium.
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Bad food #2: Sunflower, safflower, corn and soybean oils

Why they hurt: They're high in omega-6 fatty acids, which increase inflammation.
Watch out: These oils are prevalent in U.S.-made baked goods and snacks.

Swap them for: Switch to healthy olive or nut oils.