Earlier quoted context omitted.
Walnut, almond, sunflower oil are not bad for you. They're expensive. Vegetable oil as you know it and it's sold is soybean oil. Maybe another cheap oilseed like canola or corn, but that's it because it's cheap.
Sunflower oil is in the same category as soybean and canola oil, industrially extracted from seeds and consisting of the type of omega-6 that in any but the most miniscule amounts are harmful in a number of ways, and a poor source of metabolic energy to boot. Walnut, almond, etc., are good for us, but in small amounts, and don't keep well or withstand heat, all of which make them unsuitable for cooking. We need to go…
I have been hearing this for years, but I have never found a reputable scientific source for this claim about omega-6 and omega-3. All I can find are sketchy websites trying to sell something.