Do you mean oils that have turned rancid before they are consumed? I don’t really get the hate seed oils are getting. In studies they seem to have shown no ill effects. They do certainly use oils in studies that are not rancid, while your average supermarket oil might be (?).
Without a literature review, they'd certainly be a number one suspect.
Consider this statement elsewhere in the thread:
> before 1985 T2D was called adult onset diabetes considered an adult disease and 1983 was the first case of pediatric nonalcoholic fatty liver disease.
We've eaten sugar and saturated fats for ages. Of course, not everyone ate the same amounts that people do today - but we'd expect someone to be feeding their kid enough bacon (which people ate huge amounts of even ~100 years ago relative today) to give them fatty liver disease, if e.g., its saturated fats, or feeding them enough sugar.
But what people didn't eat, almost at all, was seed oils. Canola oil was not consumed at all before the 1970s - canola is a CANadian scientist created version of rape Oil, with Low Acid - rape oil itself being too poisonous/bitter to eat. Soybean oil was practically unheard of. Cottonseed oil (aka Crisco) was just being invented as a wonderfood, here to solve our problems. Today these oils, particularly soybean and canola, are the second highest source of calories in the average American diet, and the single highest source of fats. We're suddenly beset by major metabolic problems, from heart disease, obesity, fatty liver, T2D, that did not exist or existed in much smaller proportions, even in historical populations where people were eating tons of bacon or sugar. Meanwhile, we have a food source that went from "negligible" to "one of our main sources of calories." It's not proof, there are almost certainly other factors involved as well, but it's really, really suspicious. Making matters worse, what you feed animals also impacts the fat composition of their meat, and we now feed cows and pigs canola and soy.
> before 1985 T2D was called adult onset diabetes considered an adult disease and 1983 was the first case of pediatric nonalcoholic fatty liver disease.
This statement is factually false, though: https://www.sciencedirect.com/science/article/pii/S258955592.... It may not have been explicitly called that, but it was clearly shown to exist. This is not some new phenomenon that first popped up after the introduction of seed oil.
>The term non-alcoholic fatty liver disease entered the hepatology lexicon in 1986, introduced by Fenton Schaffner (American physician and pathologist).
As you acknowledge the disease didn’t even have a name until 1986, or 3 years after the first diagnosis in children.
There is nothing in the study you link suggesting kids were being diagnosed and treated for nonalcoholic fatty liver disease pre-1983 under a different name - they weren’t.
This is easy enough to confirm on google independently [1].
>This is not some new phenomenon
Yes it is, in the ~40 years since the first recorded medical diagnosis it’s become an epidemic effecting 5-10% of kids or ~10M kids in the US. There is no way this is not a new phenomenon and 5-10% of kids had nonalcholic fatty liver disease throughout history and we have no record of it.
[1] Title: Steatohepatitis in Obese Children: A Cause of Chronic Liver Dysfunction.
> Today these oils, particularly soybean and canola, are the second highest source of calories in the average American diet, and the single highest source of fats
Isn't canola oil one of the oils with the fewest saturated fatty acids, typically 7-8g per 100g?
Olive oil has ~twice as much, sunflower oil as well. Palm oil has ~7x more. And coconut oil ~10x more.
Calories-wise, all these oils are pretty much the same, typically in the range of ~800kcal per 100ml. So, I am not sure I understand the arguments against it.
Canola oil is pretty much the best bet if you want to reduce your fatty acids intake.
I didn't say saturated fats, I said fats - obviously, oil is pretty much 100% fat by definition.
Of course, it's also controversial in some circles whether saturated fats are bad, but that's a separate discussion. There is more to a cooking oil than it's saturated/polyunsaturated/monounsaturated fat ratios.
The problem is linoleic acid and our overconsumption of it. It seems to cause way more oxidative stress during metabolism, to which the brain is more sensitive. Plus it also seems to adversely affect metabolism of other kinds of fats. And it plasticizes during cooking.
The idea being in the past the only linoleic acid we would be getting was from whatever seeds we consumed naturally. With the advent of industry it's now a 20B+ business. It was hard for humans to consume so much seed oil in the past.
"Seed oils" are a nonsensical category because the main example is canola oil which doesn't actually have the problems associated with them (bad omega-3:6 ratios).
I thought the problem with seed oils is that seeds don’t want you to eat them and their chemistry may reflect that. Fruit bodies such as olives on the other hand are “designed” to be eaten and so aren’t likely to have such defenses.
Olives are a pretty weird example of something that "wants" to be eaten by us, given the insane amount of processing it takes to make anything remotely palatable from them.
Contrast with, say, sesame or sunflower seeds which can be eaten straight from the plant raw, or pumpkin seeds which just need a simple roast and peel, I'm not sure that your categorical assertion really holds up, as intuitive as it may seem.
It just has to be mammals in general. If e.g. a rape seed doesn’t want to be eaten by squirrels, to take a common seed eating mammal, there’s a decent chance that as mammals we share enough in common that whatever surface is being targeted in squirrels would affect us as well.
If something was specifically targeting birds or reptiles then it may not affect humans, but are the seeds in question in environments without mammals? I don’t think so?