I’ve seen this question asked on Reddit multiple times, and the comments usually say that sunflower oil is not healthy because it contains high amounts of linoleic acid, HOWEVER, all of them were in the context of the high amounts of Omega-6 in the American diet which doesn’t apply to me… so I would like some answers with less American diet bias.
I use extra virgin olive oil for marinades and salad dressing (and an olive oil spread instead of butter or margarine) and rapeseed oil (usually just labelled as vegetable oil here in the UK) for frying. The latter has a high smoke point, is lower in saturated fat compared to sunflower oil (also higher in monounsaturated and lower in polyunsaturated fats, a bit like olive oil although that has even better proportions of the two) and has better levels of Omega 3.
Here’s a bit of a review.
And why you might want to avoid sunflower oil:
With the issues with sunflower oil after the invasion of Ukraine the UK’s Food Standards Agency drew up a report about the substitution of other oils, which has plenty of data.
A switch away from sunflower oil should reduce levels of heart disease, following this paper: