Vegetable and seed oils have come under focus a lot in recent years due to their potential negative effects on your health, which I consider to be a very good thing (the more awareness that can be spread about these nasty little fuckers the better).
And if you’re a reader of the blog you’ll know that I refer to these often and plenty and consider avoiding these one of the most important pieces to meaningfully improving and optimizing your health today and a crucial part to eating healthy.
They’re in most of our processed food, we cook and bake with them at home and in restaurants, and they’re even still oftentimes recommended as the healthy choice.. WRONG.
Learning how (and why, to stay motivated) to avoid omega-6 rich seed and vegetable oils might very well be the best and most meaningful thing you can do for your health right now, especially in the long run, and so that’s what this page is for :).
“Seed and vegetable oils are in most processed foods today and we eat a lot of it, and learning how and why to avoid these might be the best decision for your health you can make.”
But to put first things first and if you’re not quite sure what seed and vegetable oils are yet, let’s start with a simple question.
(If you want to jump straight to the sections of why and/or how to avoid seed and vegetable oils, you can use this table of contents to do just that:)).
Table of Contents
- What Are Seed And Vegetable Oils?
- The Difference Between Saturated And Unsaturated/Polyunsaturated Fat
- Are Seed And Vegetable Oils Bad For You?
- Why Are Seed And Vegetable Oils Bad For You?
- They Provide Excessive Omega-6, Skew The The Omega-6/3 Ratio And Easily Oxidize Inside The Body And Cause Systemic Inflammation
- Mitochondrial Dysfunction
- Harmful Chemical Additives
- Omega-6 And Vegetable/Seed Oils As Our Main Cause Of Chronic Disease
- Extra Bad When Cooked/Fried And Heated (+ Trans Fats And Harmful Byproducts)
- Are All Vegetable And Seed Oils Bad For You?
- How To Avoid Seed And Vegetable Oils + List Of Specific Fats And Oils To Avoid
- Do I Need To Avoid Natural Whole Foods (Not Oils) High In Omega-6 As Well, Such As Nuts And Seeds?
- Common Foods High In Seed And Vegetable Oils To Avoid (Worst Offenders)
- How Long Does It Take Detox From These Seed And Vegetable Oils?
- Good And Healthy Seed Oil Substitutes
- Environmental Impact Of Seed And Vegetable Oils
- Vegetable And Seed Oil Recap
- Related Reading:
- Share The Article:
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What Are Seed And Vegetable Oils?
Seed oils and vegetable oils refer to the many plant-based food and cooking oils that you’ll often find in our foods and kitchen cabinets nowadays, and as the name implies they’re often (but not always) made from the seeds of various plants. With two different names, “vegetable” and “seed” oils are practically the same thing (the result is the same and consists of all fat).
All seed oils are also vegetable oils, that are made from the seeds of their plant, so they’re basically a subcategory of veg oils as well as a standalone category, while vegetable oils that aren’t also seed oils are made from other parts of the plant such as the leafs, fruits, flowers and stems.
Again, for all intents and purposes they’re pretty much the same when it comes to fatty acids and nutrient composition (they all vary individually but not meaningfully between the seed and just vegetable oil category), which is what truly matters when it comes to your health.
They’re usually highly refined and are often heated, bleached and deodorized in order to be usable for consumption.
They’re also often very high in omega-6, which is problematic for reasons I’ll get more into soon.
“Vegetable oils and seed oils are plant-based oils extracted from various parts of the plant or its seeds, that are often highly industrially processed and high in omega-6.”
For a list of specific omega-6 rich seed and vegetable oils to avoid, see further down on this page under how to avoid these unhealthy fats that are everywhere.
But before anything else and the highlights of this article, I just very briefly want to get into the differences of various types of fats, chemically and structurally, since it’s important and highly relevant to the topic and rest of the page:
The Difference Between Saturated And Unsaturated/Polyunsaturated Fat
So, before we make a deep dive into how vegetable and seed oils affect your health, what are saturated and unsaturated fats?
In simple terms, saturated fats are much more stable than unsaturated ones, of which you have mono- and polyunsaturated fats and, of which, monounsaturated ones are still pretty stable, while the polyunsaturated ones are considerably less stable, more unstable.
They differ structurally in that saturated fats are “saturated” with hydrogen atoms which also makes them solid at room temperature and able to withstand higher heat than less saturated fats (again especially than the polyunsaturated fats).
Unsaturated fats on the other hand have at least one double bond, with monounsaturated fats having one and polyunsaturated ones having at least 2 or more.
Where these double bonds are, hydrogens are missing and this bond makes them both more flexible but also more unstable and susceptible to oxidation and getting rancid.
It is not superimportant to understand this on a chemistry level to understand their (bad) effects on your health, which I’ll get into right after this, but the bad seed and vegetable oils are exceptionally high in these unstable and polyunsaturated fats, especially linoleic acid (omega-6) but sometimes linolenic acid as well (an omega-3), which is why they can become harmful and are very different from the fats we have eaten historically and traditionally.
They’re unstable inside our bodies as well (where they become a part of our tissues and cell membranes), which is problematic, and again more on this in the following sections.. So.
“The chemistry can get too advanced, but simply put, these fats are very unstable, both outside and inside our bodies, which can lead to problems.”
With that said, let’s move on to the question of the hour:
Are Seed And Vegetable Oils Bad For You?
As I’ve already touched on this and on my opinion of these oils, I’ll keep it brief and short and simple and quick and concise, in saying that YES, they are actually really bad for you, and for reasons I’ll explain further under the next heading and second question of the hour, and this is where stuff gets more interesting, namely:
Why Are Seed And Vegetable Oils Bad For You?
The reasons why these plant-based fats and oils are bad for us are several, but here are the by far biggest and most important ones:
They Provide Excessive Omega-6, Skew The The Omega-6/3 Ratio And Easily Oxidize Inside The Body And Cause Systemic Inflammation
Because these oils (most, not all) are very high in polyunsaturated omega-6 fatty acids, and excessive omega-6 linoleic acid and its oxidation and the resulting free radicals that cause damage to body DNA and tissues causes chronic systemic inflammation, these highly inflammatory oils basically cause that too.
Simple math.
So, lots of inflammation, lots of oxidation, free radicals and oxidative stress from these oils..
Not good.
Excessive omega-6 can disrupt the normal functions and composition of our cell membranes as well, once they contain too many of these (has become the norm today) as opposed to monounsaturated and saturated fatty acids.
Our omega-6 to 3 ratio has never before been so epidemically skewed as it is today, and has always been low and good evolutionarily speaking until about a hundred years ago (early 1900’s) when we started introducing omega-6 rich vegetable fats into our food supply.
Those lower levels of omega-6 in our diet and bodies (not none however, mind you), is what we’ve evolved with and adapted to and the reason we’ll get sick from and can’t handle too much of it.
Omega-6 builds up in our bodies and tissue over time proportionately to how much we’re eating of it, which is again why it’s so important to start eating less of it sooner rather than later.
It can take a long time to get rid of this built-up omega-6 in our body as well, but more on that further down!
Mitochondrial Dysfunction
The mitochondria are our little energy factories inside our cells, and very important for our overall health, energy levels and how we feel overall.
These seed and vegetable oils cause damage and impair the functioning of our mitochondria, creating yet another path that can contribute to and cause a lot of the chronic diseases that consumption of these are related to.
For more on this in particular, check out the first video of Chris Knobbe just slightly further down on this page.
Harmful Chemical Additives
Another harm with these oils that may be often overlooked, and although probably not as bad as the other ones listed, is that they often come with some harmful chemical additives and preservatives as well, since these are added during the processing of the oils to promote longevity and shelf life and enhance the yield.
Common examples are hexane and industrial chemicals such as TBHQ, BHA, BHT and so on, that intend to mimic natural antioxidants, because in nature and when not in their processed oil forms, natural antioxidants are present in the foods to protect these fats and prevent their oxidation and from going bad.
Many of these added chemicals are banned in Europe, but not (at least not yet) in the US, and it’s unlikely these types of chemicals are banned for no reason (often cancerogenic or causing other problems and disease), so, another thing to look out for for sure!
“Seed and vegetable oils provide excessive omega-6 and cause inflammation, oxidative stress, mitochondrial dysfunction and disrupts the cell membrane, on top of the harmful additives.”
Omega-6 And Vegetable/Seed Oils As Our Main Cause Of Chronic Disease
A lot of sources and research today have linked much of chronic disease to chronic inflammation, which is but one of the many reasons that chronic inflammation is bad, but instead of focusing on inflammation as the cause of our many health problems, why not focus on what causes that inflammation instead, which takes us back to our diet and these inflammatory oils again!
That’s also a much more actionable and logical view to have, since you can then actually do something about it by avoiding these polyunsaturated oils providing you with excessive omega-6 from now on.
For more information on how and to what conditions these vegetable oils are closely linked, I highly recommend these popular YouTube videos of Chris Knobbe, an opthalmologist that by now has spent a good chunk of his life researching and spreading the word about the harms of these vegetable oils and how closely they’re linked to chronic diseases (including heart disease, cancer, type 2 diabetes, obesity and macular degeneration, which are only the biggest and the ones he’s spent the most time on personally, since truth is that basically all chronic disease has increased manyfold over the last century, and could just as well be linked with their own graphs to our unprecedented increase in consumption of vegetable and seed oils).
This one below is decent as well and goes more into how unnatural the seed and vegetable oils actually are as well as a lot of the economic aspect and marketing ploys that made it come to be that these oils slowly but surely replaced the more natural and traditional fats such as lard, tallow and butter in our diet.
Read the captions for a quick TLDR, and although there are many good sources online today that condemn vegetable/seed oils, these were among the ones that I personally found (and still find) very convincing and that helped originally to really base and strengthen my views on the many harms of these oils.
And for even more on why these oils are unhealthy and what the studies actually say about vegetable oil, you can check out this as well as this page on it by Jeff Nobbs, which puts increased risk of death by vegetable oils just below severe obesity and heavy smoking, and above heavy drinking and physical inactivity, although it’s misleading imo since vegetable oils are also the very likely cause of said obesity in the first place while also probably affecting the risk of death by smoking a lot as well.
This article from Zero Acre includes a lot of the studies as well, linking consumption of these oils to autoimmune disease, heart disease, Alzheimer’s disease, dementia, obesity, diabetes, cancer and macular degeneration, so, worth checking out as well if you want to see the actual studies :).
Chris Kresser connects them to the ones above as well as with worse cognition and mental health, dementia, asthma, osteoarthritis, depression, anxiety, IBS, IBD and infertility, which is interesting but should be unsurprising considering their above mentioned connection to virtually all types of chronic disease.
“Seed and vegetable oils are very likely the main cause and driver in most (nearly all) of our chronic diseases, including obesity.”
And with all that on why they’re harmful and you want to be avoiding them, here comes another useful bit of info to know about them:
Extra Bad When Cooked/Fried And Heated (+ Trans Fats And Harmful Byproducts)
Polyunsaturated seed and vegetable oils become even more harmful when heated (as in when used for cooking with it and when used for repeatedly frying with it in many restaurants, since heat, as well as exposure to light, air or moisture causes them to quicker oxidize and go rancid as well as produce a lot of harmful trans fats and byproducts of lipid peroxidation (including things such as bad aldehydes and polycyclic aromatic hydrocarbons).
Even just being exposed to the fumes when frying in fats such as margarine is harmful and cancerogenic..
So, when heated, once or repeatedly, these oils become even more toxic, obesogenic, cancerogenic, inflammatory, rancid, pro-oxidative and so on.
You really want to avoid seed and vegetable oils for your health in the first place, but your really, really, want to avoid cooking with them or buying food cooked and fried with them.
Many of the oils are also heated during the industrial process of which they’re created, meaning they often already come with these added negative effects from having been heated, straight from the bottle.
“Don’t heat polyunsaturated seed and vegetable oils (so don’t cook with them, and of course, rather, don’t consume them at all).”
But there are exceptions:
Are All Vegetable And Seed Oils Bad For You?
Since vegetable oil and seed oil are sweeping terms that technically include pretty much all plant-based oils, you could definitely make the argument that all seed and vegetable oils aren’t bad.
However, usually, the oils referred to when using the terms are the highly polyunsaturated oils, so it’s still generally safe to assume that vegetable oil = high and easily oxidized polyunsaturated fat levels = unhealthy.
Oils such as coconut, olive oil, avocado oil (click the links for good products) and even palm oil are although technically vegetable oils not that high in polyunsaturated fatty acids and omega-6, making them healthy alternatives to “actual” vegetable oils.
But more on these, with a list of both good healthy fats and bad fats to avoid further down!
“All seed and vegetable oils aren’t bad, but those high in omega-6 and which are usually referred to when using the terms, are.”
And now to the most important piece of the puzzle, i.e. how to actually avoid them:
How To Avoid Seed And Vegetable Oils + List Of Specific Fats And Oils To Avoid
The way to avoid vegetable oils is simple and straightforward once you’ve gotten the hang of it and have been doing it for a while, since by then you’ll already know how to read the labels and what to look out for there as well as what products are seed oil-free, since you’ve read their labels and bought them before, but the main ways to avoid these oils then to begin with, are:
- Always reading the labels and boycotting anything that has vegetable oil in them, including soybean oil, canola oil, safflower oil and more (see the more extensive list of specific oils to avoid right here below).
- Never again buying or using these oils at home for things such as cooking or baking or as a spread (a list of good vegetable oil substitutes and healthy fats is available further down on this page as well!)
- Not eating fried food when eating out at restaurants, since they’re almost always fried in vegetable oils nowadays, but also avoiding most dressings that are often made with a vegetable oil base (includes processed pre-made dressing in stores as well).
- Eating more whole as well as healthy superfoods in the first place (which should be the base of your healthy diet either way), since these will naturally be void of processed seed and vegetable oils.
- Another pro tip for reducing your omega-6 consumption, which can be especially helpful and important while detoxing from the unhealthy oils and not having been clean from them for a while, is to stick to beef above other meats if you eat grain-fed, and leaner cuts of pork and chicken (if grass-fed it doesn’t matter omega-6-wise), because pigs and chickens, just like us, store omega-6 in their tissues when on an unnatural diet high in those (grains, cows don’t and will have a low omega-6 content either way), so if you’re serious about reducing your omega-6 intake, consider eating more beef!
And that pretty much covers it for avoiding these types of fats, so, simple enough, right?
Related Reading: Grass-fed vs Grain-fed Meat – Key Differences.
“Avoiding seed and vegetable oils is fairly simple once you get the hang of it.”
But as for the specific and unhealthy oils and fats to avoid, they include:
- Canola or rapeseed oil
- Corn oil
- Cottonseed oil
- Soybean oil
- Grapeseed oil
- Sunflower oil
- Rice bran oil
- Safflower oil
- Peanut oil
- Sesame oil
- Walnut oil
- Castor oil
- Hempseed oil
- Lin/flaxseed oil
That should cover most of them, and especially the most common ones, and do take note that even if the omega-6/linoleic acid is the most common and worst, even the oils that have a high polyunsaturated fatty acid content of the omega-3 kind are to be avoided, they suffer from the same types of problems as the rest when it comes to oxidation and rancidity, and you simply don’t want them in oil form, either, which is why the lin/flaxseed oil makes it to the list there at the end.
The exception to this I’d say is fresh fish oil and cod liver oils (especially capsulated ones), which you consume in small enough amounts and that have very important essential omega-3s (EPA, DHA), as well as some often needed vitamins (cod liver oil).
(Links lead to recommended products of these).
“All of the above listed oils are high in polyunsaturated fats, and most of them in omega-6 (as opposed to omega-3).”
Related Reading: List Of Inflamatory Seed And Vegetable Oils to Avoid (They’re the same as the ones above, though!).
Do I Need To Avoid Natural Whole Foods (Not Oils) High In Omega-6 As Well, Such As Nuts And Seeds?
No, you don’t.
In their whole form nuts and seeds are superfoods, especially the ones with more omega-3s such as flax seeds and chia seeds, and macadamia nuts (click the links for good products of these) for their low polyunsaturated fatty acid content, but all nuts and seeds are still really healthy for you and make for great healthy snacks, with a few smaller caveats.
Which are:
- If you have yet to cut out processed seed and vegetable oils from your diet, you’ll still want to limit consumption of the nuts and seeds high in omega-6, since it adds up and can become a lot of total omega-6 intake together. Eat a handful a day or perhaps two, and not much more than that to be golden.
- Even if you have been boycotting omega-6 oils for a while, nuts and seeds high in omega-6 are still not something you want to eat loads of, for similar reasons to why vegetable oils are bad (too much total omega-6), but sticking to 1-2 or perhaps 3 handfuls of them a day is a good amount and very healthy for you, while still being okay to eat more or a lot of them in in one sitting sometimes, just not too often or all the time!
Common Foods High In Seed And Vegetable Oils To Avoid (Worst Offenders)
To kickstart your avoidance of veggie and seed oils, it may be good knowing what the worst offenders are, the foods with seed oils, right off the bat, so that you can start avoiding or throw those out right away, and thus, the worst offenders regarding these oils include:
Most sorts of chips – Potato, sweet potato, tortilla, vegetable chips, etc, most of these contain a lot of inflammatory vegetable oil and generally fried ones on top of that, so, really bad for you.
There are, although rare, healthy veg oil-free chips such as these avocado oil chips and some of the ones included in my list of the healthiest snacks to choose.
Fried food in restaurants – We already touched on this but again, these are on the list of foods to avoid.
Most processed dressings – Again often made from a base of vegetable oil meaning they contain a lot of it, but read the labels to make sure, because as with the chips there are some that don’t, some of which I have again listed both in my post on superfoods as well as among the healthy snacks, so check those out and expect a dedicated article on these healthy dips/sauces/dressings eventually as well!
Many pre-cooked meals – Sadly, these often don’t have the sense to not include seed oils, since they’re cheap and still often recommended by some authorities as healthy and not harmful to our health.
Plant-based dairy – Yep, these dairy alternatives often contain seed and vegetable oil as their added fat content, not good for you!
Breads – Although many breads don’t have these oils, there are many that do as well, often not in huge amounts but still in high enough amounts (which imo is any at all, better to just skip and boycott these products entirely to make things easier) to make avoiding them impactful for your health.
Margarines and plant-based oils and fats – Duh, these are among the very worst offenders, being both very popular and often entirely or almost entirely made up of these unhealthy oils so, pour these out and stop buying them, for the sake of your health and your family’s.
Canned seafood – Canned seafood is very often packaged in one of the omega-6-rich oils you really want to avoid, so, watch out with these!
Most processed food with an ingredient label – I just want to reiterate that again, start reading the labels because these fats are in so many of our processed food products in the food aisles today, making that the only real reliable and sustainable way if you still want to be able to enjoy some processed products (the ones without them).
“Avoiding these foods, may improve peoples’ moods.”
How Long Does It Take Detox From These Seed And Vegetable Oils?
How Long To Detox From And Get Rid Of All The Omega-6 From These Oils?
As mentioned briefly further up in the article, detoxing from and getting rid of the built-up omega-6 from seed and vegetable oils in our bodies can take a fairly long time..
The half-life of omega-6 in the body tissues has been estimated at 680 days, i.e. nearly 2 years, and the estimated time to get clean from them if you’ve eaten a lot of these (which most of us have today) can be considered around 2-5 years.
Don’t fret it too much though, because if you start now, you’ll still likely notice good improvements in your overall health and weight in even just a few weeks or months of cutting them out from your diet entirely (I’ve heard and read a lot of anecdotal evidence on this), with gradual progress along the way, and unless you’re old enough to likely be gone within the next year or 3, you’ll be able to take full advantage of the longevity and longer healthspan benefits as well, which I talk more about early in my write-up on a healthy diet (of which avoiding these oils is an essential part).
“Getting rid of these oils (or the omega-6) can take a while, so better start ASAP, it’ll definitely be worth it in the long (and generally short) run!”
Good And Healthy Seed Oil Substitutes
And here comes the part most useful for those looking for effective and good replacements, or substitutes, to these unhealthy fats and oils.
Healthy seed and vegetable oil substitutes include:
- Coconut oil
- Ghee
- Real butter
- Olive oil
- Avocado oil
- Tallow
- Lard (even better if grass-fed)
- Duck fat
- MCT oil
- Palm oil
So, substitute these for seed and veggie oils in your cooking, baking and dressing to make a big impact on your health both in the long and fairly short run!
They’re a lot healthier mainly because they’re much lower in omega-6 and polyunsaturated fats, but also (the animal fats mainly) because they contain the important vitamins A, D and K2 whom you should probably be supplementing with already unless you’re eating liver and organ meats and getting a lot of sunshine (in which case they become less important to get from food).
“When substituting with the right types of fats, you won’t be missing vegetables at all, since the healthier fats are generally tastier as well.”
And now, sort of last but not necessarily least for a lot of people, we have the:
Environmental Impact Of Seed And Vegetable Oils
The environment can be another and added reason for why people want to be avoiding vegetable oils, and if that’s the case for you, great, whichever floats your boat and makes you eat none/less of these.
These oils can actually have a huge impact on the environment, but since it’s somewhat outside the scope of this article focusing mainly on your health, I’ll just be quick about it and then recommend you to check out this article for learning more on this.
In short though, vegetable and seed oils are bad in terms of the environment since:
– More land is devoted to growing vegetable oil crops than for fruits, vegetables, nuts, roots, tubers and legumes combined.
– They emit more greenhouse gases per kg than any other major crop.
– These oils account for 20-30% of all global land crops, while delivering pretty much no nutrients at all (veg and seed oils are a high-calorie food that’s almost completely void of important nutrients).
– Vegetable oil crops are among 2 of the top 3 drivers of global deforestations.
So, there you have it in a nutshell (from a nut that hopefully wasn’t made into oil!).
“Seed and veg oils aren’t just bad for your health, they’re bad for the environment as well.”
And now we’ll recap:
Vegetable And Seed Oil Recap
Here are the most important points:
- Seed and vegetable oils are industrially processed oils made from various plants and often the seeds of those, and a common ingredient in processed foods and for cooking.
- These oils are very bad and toxic for you.
- They’re bad because they provide excess omega-6 and skew the omega-3 to 6 ratio, cause inflammation, oxidize easily to cause free radicals and oxidative stress in the body, cause mitochondrial dysfunction, include harmful chemical additives and create trans fats, dangerous byproducts and toxic fumes when heated, and cause and are linked to a lot if not most/all types of chronic disease (Bonus: they also contribute to birth defects).
- You avoid them by reading the labels and eating more whole as well as by learning the specific oils and fats to look out for and avoid, as well as the most common food offenders containing these (see lists for all of these above).
- Not all vegetable oils are bad, nor natural whole foods high in omega-6, since good ones such as coconut oil and olive oil are both technically vegetable oils as well as unprocessed nuts and seed, but the term “vegetable or seed oil” generally refers to the oils high in omega-6 and/or polyunsaturated fats.
- Detoxing from omega-6 can take a long time, but at least you’re likely to see good results gradually along the way.
- There are many good seed and vegetable oil substitutes so that you can still bake, cook with and enjoy your fats, see list above.
- These oils are also very bad for the environment while offering people very little nutrition for all the farmland it takes up.
And that’s a wrap!
As always, please share the content and/or subscribe to our email list or on social media to stay updated, it also helps us a lot in reaching more people!
Enjoy your from now on hopefully less “seedy” lifestyle :).
“Lifestyle from now on = Less Seedy.”
/Emil
Related Reading:
The Best Healthy Diet: For Healthy Eating – Eat Like This!
The best canned oysters, clams, fulvic minerals, multi mineral and trace mineral supplements, kelp supplements and pork rinds (without seed oils and all superfoods).
Do Clams, Mussels And Oysters Feel Pain And Are They Vegan?
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Our Modern Processed Diet Still Causes Birth Defects!
