Any PUFA that is heated is ruined. Heated PUFA's are as unhealthy as transfats. Sunflower oil should be kept in a cool, dark place. High Linoleic sunflower should be in a dark bottle, just like virgin olive oil. Avoid high oleic sunflower oil unless you intend to fry in it. High linoleic sunflower oil is 65 percent omega 6. Omega 6 is vital to optimal health.
Most of the articles about omega 6 are negative because they probably used high oleic omega 6 such as canola soy and corn oil. As I stated, heated or treated PUFA's are ruined. The vast majority of store bought items are made from processed oils. You cannot use ruined goods and expect good results. Unfortunately, the experts haven't figured that out. Omega 6 gets panned because their samples were probably ruined.
It is imperative you use unheated, unprocessed sunflower oil. A teaspoon a day is all you need for your omega 6 intake. Before all the processing, there was a lot less cancer, heart disease and diabetes. Processing was done to make more money because untreated oils turn rancid fast; however, that has caused the diseases mentioned above.