I see hysteria around how bad seed oils (ie canola, sunflower etcetc) supposedly is in certain parts of the internet. Is there some actual science behind this or is this just anecdotal hype like most comments around nutrition.
I’ve traced the idea that seed oils are bad back to the Weston A. Price foundation. This talk is fascinating, whether you buy into the idea or not, and is worth watching despite being very long: https://youtu.be/fvKdYUCUca8
To summarize, our ancestors sought out the most nutrient dense foods possible. They didn’t know they were doing that, but that’s what they did. Today, manufactured foods are much less nutrient dense due to ingredients like seed oils that increase calories without a proportional increase in nutrients. Yes, seed oils give us fatty acids in abundance, but not much else.
The logic of that argument makes a lot of sense to me. Since this is r/nutrition, shouldn’t we all be wanting to eat the most nutrient dense foods we can?
The other thing to keep in mind is that most people don’t consume plain seed oils just by themselves. They are often a main ingredient in condiments and other highly processed foods. So, a person who eliminates seed oils from their diet, would also be eliminating processed foods which are likely to contain a whole host of questionable ingredients. You couple that with the person also eating more nutrient dense foods, and the person is likely to become more healthy.
So, it may or may not be the actual seed oils causing harm, but it’s hard to argue against how a person would not benefit from eliminating them.
The fear is largely based off of the production process that has lots of worrying steps and terms. There’s a video that goes round and it just looks and sounds gross. But I don’t think I need to elaborate why that means essentially nothing if it’s not reflected in endpoints.
There are rodent studies with worrying effects too. But then same logic applies.
When it comes down to it, no actual human data supports the fear of seed oils (which is a colloquial term for more than just seed-derived). This article covers every, and I mean every, argument against seed oils in detail. With particular reference to performance against saturated fat, which is typically where the anti seed-oil camp come from.
I’d also recommend searching the subreddit because this does come up about once a week or more.
Edit: Scroll down to see my prediction come true.
The only thing I’m aware of is the research suggesting vegetable oil (which I believe is soybean based?) has some strong relationship with depression:
https://pubmed.ncbi.nlm.nih.gov/28850110/
And some connection to higher blood pressure:
https://www.scielo.br/j/clin/a/hpTYSHgVDTzvScTG7rQKvqq/?lang=en
But a lot of this is just the quality of diet that people who consume these a lot is. After all, consumption of high rates of fried foods is bad for blood pressure and the weight issues related with that kind of diet can feed a low body image as well, so I don’t know how much of this is just correlation with third cause, and what’s actually causation.
I’m going to link the pubmed search for canola oil & inflammation because there is a ton of research on it, but mainly the issue is due to pro-inflammatory responses to high amounts of omega 6 compared to omega 3s and the cytokine response it can inflict
When exposed to heat, light, and chemical inputs, as is typical in restaurants and food processing plants, seed oils become toxic to the human body. Overheated and oxidized seed oils, produce trans-fats and lipid peroxides as byproducts.
We have plenty of human outcome data that shows when replacing saturated fat with PUFAs it lowers your risk of heart disease, perhaps even better than whole grains.
High quality human outcome data always trumps mouse studies and mechanistic speculations. Just because its processed does not mean it is unhealthy (natural fallacy).
Most importantly, since the general public are not experts on this sort of thing and wouldn’t have a clue on who the actual experts are, it’s probably wise to follow what the majority of experts say and not some goober outliers who think they can over turn 70 years of science just to sell books.
I haven’t looked up any science to it but my anecdotal experience suggests there are inflammatory properties…example is me with my arthritis (immune system kind). My joints skin, lips and eyes will tell me if there is canola, sun flower or safflower oil in something.
I stick to olive oil, coconut oil, and grass fed organic (or organic but doesn’t pay for the label) tallow and butter. Same goes for other traditionally inflammatory foods, they are a no go.
And ime, doctors who don’t have much knowledge/experience with the food side of dealing with arthritis will dismiss my claims food makes a difference.
But here’s a picture of my hand 15 minutes after having something with (I think) safflower oil.
https://i.imgur.com/IhvOBHr.jpg
My fingers get super red then it’s like all the moisture gets sucked out of them and in a few hours I go from nice soft stretchy normal skin to dry, cracking & bleeding fingers, chapped lips and sticky joints. And this is repeatable.
I’ve been doing the diet thing for like 10 years so I have a pretty good grasp on what my body tends to like and not like. And yeah, all the traditional inflammatory foods are a no go.
Most oils are heavily processed. We haven’t evolved to eat any oils. The less processed the oil the better as is the thinking with healthy intake of other foods. If you can’t process it in your kitchen, it is essentially ultra-processed junk food.
The big factors that control the breakdown of fats are:
Omega 6 oils don’t fare well in this:
Seed oils are therefore more likely to go rancid sitting around in your cupboard and when you heat them up they break down more easily, producing toxic aldehydes. These issues show up the worst in deep frying as there’s a lot of heat and a lot of oxygen around.
Note that olive oil is also unsaturated and will also go rancid over time. If you choose to use seed oils, it’s a good idea to buy the smallest container you can find.
Most data points to poly-unsaturated fat (oils) as a good thing, especially when replacing saturated fat with them.
Nick Hiebert’s blog has a whole thing worth reading.
I don’t know as they deserve the villain status that maybe sugar does, but seed oils tend to contribute to the omega-3/omega-6 imbalance that is associated with inflammation. That’s a generalization, so it’s really oil and brand dependent.
Not really, I personally think it’s because people are studying low quality oils. A lot of the time they get cut with with additives or less an optimal oils to bulk out product because it isn’t cheap to make. Yet canola oil is the cheapest oil you can buy.
Others already have provided great studies to have a discussion on the molecular and biological aspects of this food science question.
However, holistically, I believe that the best oil is the oil you don’t use. All vegetable oils and all concentrated animal fats are highly dense, highly caloric foods. In a context of ever-increasing obesity rates, I believe the public health advice should be to cut back on all of them, whichever one you choose.
all i can tell you is how I feel when i consume seed oils. Always starts in my left foot, bits of pain Then my knee….
i go off of em and in time it stops hurting and im better .. Its like clock work
Yes
