If you have the cognitive capacity, you could remember which ones are engine greases, and which ones are lacquers. Stuff like soybean oil and safflower are lacquers, basically bottom-shelf linseed oil. Linseed is what linoleic acid is named after. Rapeseed oil, much less prone to hardening, is engine grease.
If you eat engine grease it's almost exactly like pouring the contents of your oil pan into the fuel tank. The engine knock will announce you've done something wrong, but your engine will break down within days primarily due to less-obvious problems. Biology is more sophisticated than engineering, so it takes longer to break down, but it's the same dynamic.
Meanwhile, the lacquers are what cause atherosclerosis. If you want to seal a dead wooden cabinet or chest, a plaque is just the thing. In shocking news, you don't want hardening preservatives in your living arteries. That's bad.
Nutritionists say linoleic acid is essential, but nutritionists are full of shit. Nutritionists also say you can't live without retinol and ascorbic acid, which is flat false. And essential is the wrong word you illiterates, it's something vital, rather than part of an essence. (Vitacid rather than vitamine.) It's not impossible that linoleic is necessary, but even if so, you only need tiny amounts. A pound of beef contains 400 milligrams of linoleic, 4% of the [[[recommended]]] daily value, and whatever it has is plenty. Probably even lower in grass-fed beef.
Cockroaches release linoleic acid when they die as a warning signal. It's intended to be noxious - that's why plants like it. Can plausibly posit all mammal linoleic acid is contamination, not nutrition.
Explicitly to put a fine a point on it as I can, the fact the hateful eight are toxic was very predictable. There was no need to check. Not exactly subtle rocket science. Don't eat things that aren't food.
Generally it's chronic damage that gets you. If you cut your arm,
you're likely to make a full recovery. If it's deep enough you'll get surface scarring, but you will regain full function. If instead you strap
something to your arm and let it chafe a bit but repeatedly, you can
permanently kill your hair follicles, among other issues. The way ear
gauges deform the ear can be done on most body parts. Startlingly small
amounts of pressure, unevenly applied, can warp your bones.
The fact seed oils don't immediately make you throw up is a red flag, not a good sign. It would be better if they gave you biological engine knock. Presumably if you're dumb enough to keep eating them for generations, you will evolve the senses required to suffer acutely when exposed to them.
Your body tries to sequester this stuff rather than use it for fuel. If the liver gets to it in time, it packages it and tries to shove it into the attic to be forgotten. In this case the attic is found at the waist. Because they are oils, the kidneys can't easily filter them out, so you can't simply piss them away. The only real way to get rid of them is to burn them, suffering the illness your liver was trying to save you from. Bonus: the liver has a sharply limited capacity, and large amounts of engine grease flood the detox pathways. Double bonus: the packages don't stop them from being inflammatory, they merely stop the immune system from removing the inflammatory agent. Burning them is important. In other words, not eating them in the first place is very important.
Presumably if you were dumb enough to eat this stuff for generations, you would evolve to package it into stools for elimination.
The sunflower seed doesn't want its own oils turning into rancid lubricant, so it's full of antioxidants. If you eat a whole seed, you get the antioxidants &c along with the oils, so it's not so bad. See also: peanuts, sesame, flax or linseed.
During the refining process, the plant's natural buffers are removed. The oil is [pure] now. Briefly.
Much of the reason seed oils have to be [deoderized] is because the highly ungentle refining process turns all sorts of things rancid. It smells rotten because it's rotten, cue midwit meme. Part of the deoderization process removes the rotten compounds, and part of it turns them into odorless but still noxious compounds which stay in the lacquer or lubricant.
Fun fact: rancid oil catalyzes the oxidation process. There is no way to heat industrially processed seed oils without fucking yourself.
Another thing that should have been obvious in prospect: coconut oils being heat-resistant. It lives in the tropics and it's brown. Further it expects travel in the sun, not hide in the shade. By contrast northern seeds benefit from natural refrigeration.
From what I understand, during WWII the disruption in oil supplies and high demand from planes and tanks meant no mineral oil for lubricants, so they turned to seed-based alternatives. Not great, but good enough. Lots of factories spun up to turn rapeseed into engine grease. It was deoderized for the comfort of the engine users, rather than to trick folk into thinking it was edible. Once the war started winding down and black gold supply lines stabilized, they had all these now-redundant oil factories, so they captured some regulators to let them sell it as [[food]] instead of having to take a haircut.
Crisco, industrially adulterated cottonseed oil, predates this. WWII served as a popularizer for these bastardized pseudo-foods.
Don't be like me: keep linoleic and linolenic acid unconfused, despite the fact they're both named after linseed oil.
Or maybe linolenic oil is also biologically unnecessary and it doesn't matter.