Ray Peat has a lot to say about the polyunsaturated fats:
2015-03-14 I already discovered that I could not tolerate canola oil (=rapeseed oil). I will get inflammation all over my body and be in a lot of (left sided) pain when I eat that stuff. But I always figured the other unsaturated oils wouldn’t be that bad. I thought I’d always eaten sunflower oil and other unsaturated oils without any problem.
But now that I’m slowly getting better and leaving a lot of symptoms behind me, I find that a few are really stubborn: inflammation is one of them, pain is another. During the last two weeks I found out that sunflower oil also causes my left sided pain, only I have to eat more of it to get this “result” than I would have to by eating canola oil. But the pain was just as bad and also took about 4 days to subside.
When I eat PUFA’s I get deficient in B6. magnesium and vitamin A and probably several more vitamins and minerals that I’m not aware of.
I don’t have this problem with olive oil.
Estrogen, thyroid hormone and vitamin A
While the competition by PUFA for protein binding sites blocks the effects of thyroid hormone and vitamin A, the action of PUFA on the sex steroid binding protein (SBP, or SSBG, for sex steroid binding globulin) increases the activity of estrogen.