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Seed Oil Toxicity Debunking The Debunkers

Seed oil Toxicity: Trend or Truth?

Controversy Over Seed Oil Toxicity 

If you’re being more conscious about the presence of seed oils in the foods you and your family eat, you’re not alone. This has become a big deal over the past few years and I gotta admit I’m partly to blame for this. I wrote about their toxicity in my earlier books, and changed how the Lakers eat. The results were astounding.

In the past 12 years, there has been a significant shift in the way people think about the health effects of vegetable oils, with more vegetable oil-free products appearing on grocery store shelves. Still, most of our foods are soaking in these nasty oils.

I think this is because doctors are scientists at heart. We are conservative thinkers. I’m not talking politically conservative. I mean in the sense that we are loathe to adopt new ideas unless presented with sufficient data. I needed to read entire textbooks and thousands of scientific publications before I was convinced that support for my entire nutrition education rested on nothing but a house of cards.

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Dr. Cate dismantles the lie that seed oils are healthy, which may the biggest lie about nutrition and health because it’s so insidious.  

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Dr. Shanahan has had a significant impact on my practice of medicine. I am known as a Low Carb Doctor, but I never really appreciated the negative effects of processed seed oils on the health of my patients. I highly recommend The Fatburn Fix to my patients and have a loaner copy in my waiting room. It is amazing how quickly blood sugars and overall health improves with cutting seed oils. It is not just about the carbs!

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Lauren Smith

Saved my life

I would like to thank you for literally saving my life. Back in February, I had to be hospitalized while on vacation in Phoenix with an A1C of 11% and had to start taking 2 types of insulin and 2 other meds. I read the Fatburn Fix in April, and followed the program to a tee, and I’m down by 15 pounds, 6.8 A1C, and only one once weekly diabetes medicine. 

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Extraordinary claims require extraordinary evidence.

Doctors have been told for decades that vegetable oil is good for you, so it’s understandable that they would find the notion that maybe they’re not so great to be an extraordinary claim.

I’m happy to say that the number of people steering clear of seed oils is growing larger every year since the first publication of Deep Nutrition in 2009. It’s now become a small army. But the anti-seed-oil movement also seems to have spawned an army of armchair quarterbacks who are creating a bit of a problem. Although they get the gist of the message and are giving better diet advice than most doctors (like this guy), getting the gist is not enough. In order to convince trained physicians and dietitians to abandon long-held beliefs, you have to have more than a little knowledge. Ultimately, they’re sending the message that maybe this whole seed oil movement isn’t ready for prime time.

The devil’s in the details and a little knowledge is a dangerous thing. So let me help clear things up a bit by discussing four of the claims buzzing around the web that health professionals are likely to run into. Together, they discourage further interest in looking into the health effects of these oils, effectively waiving off most otherwise interested professionals. I’ll also give you the necessary details that put these claims in a different light.

What they Hear: Linoleic acid is the reason for seed oil toxicity. 

Linoleic acid is a polyunsaturated fatty acid found in high concentrations in seven of the eight members of the Hateful Eight. 

The disconnect:

Linoleic acid is not the problem with seed oils. The problem is the oxidation reactions that occur during manufacturing of these oils, and that continue to occur after they leave the factory. They also occur in the bottle after you open it, in the food as you’re cooking with it, and in your body, after you eat it.

What they hear: Seed oils are bad because they contain hexane.

Hexane is a known carcinogen used in the processing of vegetable oils. Even though it is present in trace amounts in non-organically labeled vegetable oil products, it’s a major reason that vegetable oils should be avoided at all costs. 

The disconnect:

Hexane is bad but it’s not the major problem.

No doubt hexane is not good for you. No one would question that. But according to the doctor I mentioned earlier, we inhale quite a lot more hexane when we fill up our cars with gas than what we eat when we eat foods cooked in canola. I have no reason to doubt that claim. But that’s not the reason to avoid vegetable oils at all costs. The reason is it’s a fireworks display of lipid oxidation products. You can learn more about one such byproduct here: “Formation of modified fatty acids and oxyphytosterols during the refining of low erucic acid rapeseed oil.

What they hear: Seed oils are inflammatory because of an omega-6 to -3 ratio imbalance.

The idea here is that many seed oils are high in omega-6 linoleic acid, and that is an “inflammatory” compound. 

The disconnect.

Seed oils promote inflammation due to oxidative stress, not because of their linoleic acid content.

Although its true that linoleic acid can be metabolized into an inflammatory eicosanoid that can promote things like blood clotting and tissue swelling, linoleic acid cannot. It takes several biochemical steps to be converted into that inflammatory eicosanoid, and each of the several necessary steps only happens under certain circumstances. Cells are tiny control freaks, and they tightly regulate each of those several necessary steps.

A diet rich in pro-oxidative seed oils undermines the cell’s ability to regulate these and every other process.

Dr Cate Quote about seed oil versus sugar
One reason why vegetable oils are worse than sugar.

What they hear: Human trials fail to prove seed oil toxicity.

There is an apparent absence of studies showing that these oils are toxic. Indeed, there are numerous studies seemingly showing the opposite. Mazola bottles claim their corn oil is “heart-healthy.” If these oils are so toxic, where is the hard data?

The disconnect:

Medical science has been operating without any understanding of oxidation for so long that it rarely even enters the research process. When it does, it’s with a superficial understanding of the necessary information. Therefore, oxidation, rather than being a central focus of nutrition research, is at best an afterthought.

Researchers are people. They’ve heard the same mantra that we’ve all heard for the past 70 years, that animal fats are bad and vegetable oils are healthy. This means they go into nutrition research with a foregone conclusion.

With that in mind, you might wonder why do research at all?

Here’s where we need to understand the connection between politics and food. This is a whole other discussion that deserves its own article. I’ll provide links to some excellent lectures on the topic, below.

It boils down to feeding the masses from the bottom of the food chain where calories are easier to produce for an ever-growing population. In the battle for funding dollars, the winners tend to be those researchers whose messages align with that goal. This goes back to Ancel Keys and the diet-heart hypothesis and continues with the Adventist physicians who distort their research.

When you’re talking nutrition, you’re talking biochemistry. The subject of biochemistry does not readily lend itself to sound bites. But if you want one, I’ve got one for you. Get seed oils out of your life, now.

Not convinced? Read my upcoming book.

The Scientific Support for Seed Oil Toxicity

All of the claims I make about seed oil toxicity are supported by science. Dark Calories contains over 500 scientific citations including human trials. You’ll find fascinating interviews with experts inside the edible oil industry who work to mitigate their toxicity. And you’ll meet doctors who are using vegetable oil avoidance as a key component to helping their patients recover from serious diseases.

You can order it today!

The Politics of Nutrition Science

Meat and The Politics of Nutrition By Adele Hitte [HERE]

Belinda Fettke – Religious Anti-Meat Agenda (Seventh Day Adventist Church) Gary Fettke [HERE]

Who writes our dietary guidelines, can they be trusted? [HERE]

With over two decades of clinical experience and expertise in genetic and biochemical research, Dr. Cate can help you to reverse metabolic disease and reshape your body.

Please note: Please do not share personal medical information in a comment on our posts. It will be deleted due to HIPAA regulations.

This Post Has 12 Comments

  1. I think you might have a typo in this sentence in the third section. It contradicts itself as written.
    “Although its true that linoleic acid can be metabolized into an inflammatory eicosanoid that can promote things like blood clotting and tissue swelling, linoleic acid cannot.”

  2. Dr. Cate,

    Sounds as though you fundamentally disagree with the “Avoid excess Omega 6 vs. 3” essence of Dr. Chris Knobbe’s book, “The Ancestral Diet Revolution”.

    Is this correct?

    If so, that would also imply you also disagree with the book of Dr. Phillip Ovadia, M.D. Ovadia is one of my own doc’s, while Knobbe is a personal friend, not one of my own per se docs.

    I’m a 70 year old healthcoach. I’ve been a Certified Financial Planner for almost 40 years, and I’ve also turned into a health coach to clients, friends, and family since I got T2D in 2015. It freaked me out sufficiently that I jumped online, found and studied the heck out of Drs. Jason Fung, (the now late) Sarah Hallberg, Peter Attia, Robert Lustig, etc., and fixed the diabetes and got off of metformin within six months.

    Now, although I’m still working and running my financial planning practice in downtown Fort Worth, and helping people with health coaching anytime I can, I’m also attempting to survive Stage 4 melanoma that was diagnosed with a semi-emergency left brain surgery on 11.30.21. That 2″ left brain tumor was removed, and my three left lung tumors are now reduced, in half, size-wise by a year of immunotherapy (Yervoy and Opdivo). And one of those three lung tumors is actually gone now. Unfortunately, the five radiation treatments following the initial brain surgery fried my left brain with five serious marble sized areas of RN (radiation necrosis). So, my second brain surgery was to reduce those. Four of the five RN areas were surgically removed and one was left as it had two brain blood vessels running through it. My second left brain tumor, thank God, only 2mm in size first appeared in January of this year. And, it was 3mm then. So, perhaps it really is shrinking.

    So, amazingly, with my two good neurosurgeons and and two oncologists (one of whom is a per se melanomist), I’m still here for now, right at 2.5 years, and with the two most annually deadly cancer problems available. Number one cancer fatality globally is lung cancer (mostly due to smoking), and number two is brain tumors. I’ve got number one, and number two and have amazing survived with both for over two years! Thank God.

    Anyway, you can likely now see why I’m as interested in your area of work as I am, with both my health coaching work, and my own pretty darn serious efforts at continued survival. I’m 70 years old, a financial planner, a cattle rancher, a health coach, and a serious survival from S4 cancer worker. I live on a ranch 40 miles northwest of downtown Fort Worth, where my financial planning practice is (two hours of driving to and from work), with Kamee, my wife, Virginia, my 94 year old Mom, and Cate, our 19 year old only child who just finished her first year in college at SMU in Dallas. Cate actually took a nutrition course and successfully completed it in high school.

    Anyway, I hope you can now see why I’m seriously trying to figure out why you’re seriously suggesting that the modern extreme imbalance of the current dietary Omega 6 vs. Omega 3 imbalance is not the principal problem with most plant/seed oils. My understanding is that the Omega relationship should ideally be between 1 to 1 and maybe 2 to 1. But, it is currently, at least in the U.S., closer to 20 to 1. I understand this to be a radical nutrition based problem that creates a major, major problem with our metabolic health.

    Are we in disagreement? What’s going on here?

    Thank you very much for a serious response.



    1. Hi Guy! Thanks for your interest in this vitally important topic .

      Dr. Ovadia is a great doctor. I’m an admirer. Just this week we recorded a podcast on his platform and it was a great conversation that included my reasoning for focusing on oxidation over the ratio. I hope you can listen to it when it’s released around June 11.

      I’ve discussed the ratio versus oxidation issues with Dr. Knobbe, too, at some length. And he seemed to agree.

      If we’re going up against huge moneyed interests trying to shut down the warnings it’s important to have science on our side. And there’s an overwhelming amount of science showing how these oils promote oxidative stress, which is the root cause of health problems. So much so that I had to write a 500 page book to cover it.

      I also discuss vegetable oils and cancer.

      1. I am not a doctor or a scientist, but I have been researching these topics for about 30 years in order to sift out the truth about nutrition, i.e., what is and isn’t healthy to eat and why.
        I went through a phase of O6 to O3 ratio being THE most single important factor. Seed oils were of course out (good thing). Grassfed or wild products were good, the more natural the diet of the critter the better the food derived from them, whether it was beef, pork, chicken, fish, eggs, milk, cheese, butter, or wild game.
        The problem with that approach is that if you go first and foremost by the O6/O3 ratio, you have to eliminate what are obviously healthy chioces. Like raw nuts, sprouted pumpkin seeds, avocados (and avocado oil), coconut (and ev coconut oil), and olives (and evo oil). Macadamia nuts and oil are about the only permissible chioce, by ratio. Something was missing here, so I dared to not eliminate those thing from my diet and kept researching.
        Enter oxidation. It explains the above paradox perfectly. Nuts in their narural state have compounds to prevent oxidation (go figure). Cold pressed oils (as opposed to heat processed), ditto. It oxidation that’s key. It also explains why Bonk probably had a 1:1 or 2:1 ratio of O6/O3. Nuts are seasonal, and hard to find before other critters do in the wild, and Bonk wasn’t cold pressing olives, avocados, or coconuts for the fat inside (they weren’t even around back then). There is evidence for nut consumption by Bonk and his friends though. Just saying…

    2. Regarding your cancer, I wondered if you or other readers had looked into Fenbendazole / FBZ (Merck’s Panacur / Safe-guard) and the Joe Tippens Protocol. Reportedly not approved by FDA for human use (yet) though; conversely, Mebendazole (Vermox) is as a dewormer but per Tippins in the following, possibly less effective as an off-label cancer treatment.

      I have zero background in the subject and am not medically qualified.

  3. I cook with olive oil, but I eat hot ten-grain cereal almost every morning into which I throw a variety of nuts and dried berries. I always use organic berries, but safflower oil is always used. I can’t find an organic brand that does not coat their dried berries in safflower oil. Do you know of a brand that doesn’t?

    1. I also dislike that fact that most of the seeds, nuts and dried berries are, more often than not, coated in some sort of oil to preserve them. There must be a message in there somewhere. That’s one of the reasons I lean towards in-season fresh berries (well rinsed) rather than the “shelf-stable” dried options.

      On a different point, apparently, we should avoid high-temperature cooking with olive oil and instead use avocado or coconut. They apparently both withstand the temperatures of cooking better than olive oil. Olive oil is best consumed at room temp on salads and such. I read it on the internet, so it must be true. 🙂

    2. A friend of mine gets dried cranberries and dried cherries without seed oils on etsy. You might try there. Probably should not cook with olive oil. Use ghee, butter, lard or tallow . Been on this diet for years since Dr Cate was my primary physician in CA. She told me to stop eating grains too. No more oatmeal or grain breakfast cereals. Fresh eggs every morning now unless i am doing a periodic fast. Also limit fruit in general. But I do like dried dates and the sugar/oil free ones my friend sends me.

  4. Another fascinating article by Dr cate. Some thoughts on it.

    Shame on doctors, nutritionists, and scientists for accepting dogma instead of being skeptical. Science as I was taught and executed should be skeptical and free of preconceived notions.

    The huge roadblock , in addition to the bias above, is economic and political. Think of the revenue that would be lost by ADM, Carrillo, and the like. They will fight this tooth and nail and use all their political influence.

    We need an ally in congress.

    1. Center For Science in the Public Interest, CSPI, lobbies for changes in the food industry. Among their achievements are: product labels now include trans fats, they now include added sugar, Happy Meals had to include healthier options, and we now know the calories/nutritional facts of fast food. I’m not sure whether they have a position on seed oils.

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