Every cell of the body needs fats. The structure of every cell in the body is made from fatty acids and these structures control everything. When you don’t have the proper fats, you don’t have proper cells and when you don’t have the proper cells, you don’t have proper function.
There have been discussions that seed oils and vegetables are toxic because of their polyunsaturated fatty acid (PUFAs) composition.
I recommend reconsidering this notion, at least the nuance of this discussion.
Vegetable and seed oils are not toxic because of their PUFA composition. They are toxic because these oils are oxidized and rancid. The oxidative species within these seed oils make them highly inflammatory and toxic for human consumption. The PUFA count happens to be high in seed oils. Yes, the high PUFA levels do not exist in any natural foods, and the unstable PUFAs make the oils rancid but it’s not the PUFA content that is the root-cause issue. The main issue with seed and vegetable oils is that they are rotten upon consumption.
In order to understand this process, we have to understand how the body uses and breaks down fatty acids.
Digested Fats and Prostaglandins
Fats are primarily digested in the duodenum (small intestine) with bile salts (from the gallbladder), and these salts emulsify the fats. With bile salts and lipase (digestive enzymes released from the pancreas), these fats convert to triglycerides. (Note: excess carbohydrates also convert to triglycerides).
Fats are transported into the lymphatic system and transported through the body. Fats are also used for every single cell wall lining. (Proteins and carbohydrates are transported through the portal system, and transported to the liver.)
If you struggle with poor lymphatic health, you may have difficulty absorbing and utilizing fatty acids. A good lymph detox, dry brushing and daily rebounding are all great options.
Additionally, fatty acids are sent to the liver, where the liver (with other cofactors) can make different forms of fatty acids. For example, alpha linolenic acid (ALA) in the liver can convert to Eicosapentaenoic Acid (EPA) and very small amounts of Docosahexaenoic Acid (DHA). Fatty acids are also sent to the heart, as fats are the essential fuel source for the heart. Excess fatty acids are sent to adipose tissue (our body’s fat stores).
A conjugated form of fatty acids is prostaglandins. Prostaglandins are fatty acid eicosanoids made from arachidonic acid via cyclooxygenase and likely synthesized in the cells’ membranes. Prostaglandins are hormone‐like substances the body cannot do without, and they occur in almost all body tissues and fluids.
Prostaglandins have multiple functions including:
- Controlling inflammatory function (pro- and anti-inflammatory functions)
- Dilating bronchial tubes
- Increasing blood flow within the kidneys
- Providing the fine tuning needed for maintaining homeostasis within the body
- Regulating the cell’s communication system for doing things like opening and closing channels (messengers)
To control inflammatory function, the body needs the ability to both inflame and anti‐inflame. The body inflames to heal before it anti‐inflames. The body needs inflammation, but it requires the inflammation to be balanced and controlled. One of the reasons for chronic inflammation in the body is imbalances in the prostaglandin fatty acids.
And there are three groups of prostaglandins that control this process:
- Anti-inflammatory: PG1
- Anti-inflammatory: PG3
- Pro-inflammatory: PG2
Creation of Prostaglandins
Prostaglandins require cofactors and stimulators (see graphic below) but they also have inhibitors. As cofactors, prostaglandin formation requires good gut health, proper liver function, enzymes (e.g., delta-6-desaturase—made from zinc, magnesium and B6), and many stimulating nutrients (e.g., vitamin C, vitamin B3, B6, zinc and low dose vitamin E).
In prostaglandin E3, you can see how ALA can convert to EPA (and very little DHA) but remember, you need all the proper cofactors and stimulators. To be fair, some people have a genetic predisposition making it challenging to convert ALA to EPA. This is why most knowledgeable nutritionists recommend EPA from fatty fish, not from chia, hemp, flaxseeds or walnuts.
The human body requires all fats for optimal health.
The difference between good fat and bad fat is in the way they are processed and not in the inherent nature of their natural source. Of course, the exception is the human-made seed and vegetable oils like canola, soy, and cottonseed.
Tangent: if you look at the prostaglandin inhibitors, these factors inhibit inflammation. If we have too much inflammation, we feel it with physical symptoms. The inflammation is an intentional cry from the body: it allows the body to heal the inflamed area and enables us to know that something is wrong. When we take NSAIDs, steroids, and excess vitamin E and fish oils, we are masking the inflammation. This is also why we should ideally let fevers run their course.
Polyunsaturated Fats: (Prostaglandin) Arachidonic Acid (Omega-6)
Omega-3s and omega-6s are considered polyunsaturated fatty acids. Foods in their natural form are high in omega 3s. Cold-water fish, insects, and flax seeds are all rich in omega-3s. Industrial vegetable and seed oils are unnaturally rich in omega-6 polyunsaturated fatty acids.
The polyunsaturated fats are very unstable, and with any exposure to heat and light, these oils become rancid. My canola oil article talks at great length about how seed oils are created and why the production process makes these oils toxic for our health.
I delve into how these oils are heated over six to seven times with high heat and chemical solvents. The processing of these oils guarantees the rancidity of every single vegetable and seed oil. These oils are oxidized, rotten, and highly unstable fats that cause inflammation in the body once consumed.
Our body’s innate wisdom can tell when food is spoiled. Our stomach turns, and we try hard to hold onto our insides. We can’t tell these vegetable oils are rancid because they are deodorized to mask the rancidity.
Hydrogenated fats are polyunsaturated seed oils pumped with hydrogen and heated at very high heat. These hydrogenated polyunsaturated fats create solid fat at room temperature: hello margarine.
Trans-fats are a byproduct of the hydrogenation process and are harmful to humans. Trans-fats interfere with the synthesis of critical fatty acids in the body. Any food with less than 0.5 grams of trans fat per serving is allowed to be labeled as having 0 grams of trans fats.
Additionally, through their processing, some seed oils become hydrogenated trans-fats, but they are not required to be listed as trans fats. (If you only consume animal fats, this will be a non-issue.)
Settling the Science with Dr. Paul Mason
I spoke with Dr. Paul Mason recently. He explained that arachidonic acid, a polyunsaturated omega-6 fat, is not inherently inflammatory. Arachidonic acid will only turn into inflammatory substrates if an inflammatory trigger occurs.
We discussed a 2019 study by Jeff Volek and Stephen Phinney, “Dietary carbohydrate restriction improves metabolic syndrome independent of weight loss.” They found that low carbohydrate participants showed an increase in arachidonic acid levels (a polyunsaturated omega-6 fat), yet all inflammatory lab markers were reduced.
This 2019 study By Volek and Phinney et. al., demonstrated that omega-6s in isolation is not the issue.
Diabetes and Seed Oils
Dr. Mason cites one 2008 study that measured glycemic instability (making blood glucose go up and down) to test oxidative stress. They measured the oxidative stress that affected endothelial cells lining the blood vessels. The study found that fluctuations in blood glucose levels are far more problematic than persistently high but flat blood glucose levels.
Back to the 2008 study, they fed the participants oxidized seed oils. They then measured oxidation entering circulation in the body and found it remained in place for eight hours in the non-diabetics and well-controlled diabetics.
The people with poorly controlled diabetes, with large fluctuations (more fluctuations usually means more oxidative stress), had persistent oxidation circulating the body for three days or 72 hours.
The oil consumption amounts were the same for all groups. However, the response in the poorly controlled diabetics was starkly different. This study found that when people have poor blood sugar control, diabetes makes the oxidation from the seed oils worse and also, consuming seed oils makes the blood sugar control worse.
If persistent oxidation circulates the body for three days, what does that mean when most Americans (and children) consume these seed oils daily?
It is the oxidation and the oxidative products of the seed oils that are toxic. The seed oils happen to have higher omega-six markers. It’s similar to how we blame cholesterol for heart disease when cholesterol happens to be an innocent bystander at the cardiovascular event. It is a difference of association vs. causation: the causation is the oxidative stress from rancid, unstable oils and the association is the polyunsaturated fatty acids. (read it again).
When you factor in that half of the U.S. population is prediabetic or diabetic and how the average American consumes 36 pounds of cooking oil yearly, is it any wonder why most of the U.S. population is sick and obese?
An estimated 96 million American adults, aged 18 years and older, had prediabetes in 2019, and 37.3 million Americans had diabetes.
Image Source: Pew Research
Graphic Source: CDC
To reiterate (since the fear-mongering is very real and pervasive): the issue with seed and vegetable oils is their oxidation and rancidity: it is not the amounts of omega-3 or omega-6 polyunsaturated fatty acids. The omega-3 and omega-6 fats are unstable, which causes oxidation, but it’s from the chemical processing and heating of these oils.
We are sick because we have processed our grains and adulterated our fats.
PUFAs in Meats
So if grain-fed animals ate seed oils, they must have more rancid polyunsaturated fatty acids.
Did you catch that?
We cannot eat rancid fat on grain-fed meat; you would be eating spoiled meat. Remember, we cannot determine if seed oils and vegetable oils have gone rancid because the manufacturers deodorize the oils.
You would know if meat is rancid. You also don’t heat your meat 6 to 8 times with chemical solvents.
Considering the grave concerns over omega-6 polyunsaturated fats in our grain-fed meats, even if there was truth to PUFAs from grain-fed meats causing us to store more fat, the amounts in grocery store chicken, pork, and fish aren’t the reason for obesity.
The PUFA numbers in meats are nowhere near the PUFA numbers in seed oils.
It’s not the PUFAs that are the issue. It’s the oxidative stressors in seed and vegetable oils.
We are conflating two things that don’t have any scientific backing.
How is this any different than when Ancel Keys blamed cholesterol for heart disease with his notorious Seven Countries Study? His seven-country study demonstrated that the countries that ate the most saturated fats had the highest rates of heart disease.
The funny thing is that the original study has twenty-two countries. He chose to exclude countries like France and Norway—both countries consume a lot of saturated fats but did not have high rates of heart disease. He also decided to exclude countries like Chile, where they eat minimal saturated fats but had higher rates of heart disease.
So again, how is this different than PUFAs being blamed for everything? Context matters.
The Anti-PUFA Studies
Since the anti-PUFA advocates love to cite studies. Below are studies that are used against consuming PUFAs. Listen to your favorite anti-PUFA advocate and one of these studies will likely be cited.
There is a lot of research against omega-6 polyunsaturated fatty acids. Instead of debunking each one, I will group them with my counterpoints.
Remember, I’m not saying in any way that rancid seed and vegetable oils are safe. The omega-6 in these oils make them highly unstable and then the processing of these oils make them toxic.
These five studies below use seed and vegetable oils to demonstrate the toxicity of polyunsaturated fatty acids. Where’s the chicken, pork and fish?
- Soybean Oil Study
- Soybean Oil Study 2
- Omega 6 Vegetable Oils
- Linoleic Acid Makes You Fat Study – This study posits that “The adipogenic effect of [linoleic acid] can be prevented by consuming sufficient EPA and DHA to reduce the AA-PL pool and normalize endocannabinoid tone.”
- Soybean and Sunflower Oil Study
This fascinating study (cited many times), “Soybean Oil Is More Obesogenic and Diabetogenic than Coconut Oil and Fructose in Mouse: Potential Role for the Liver” concluded that soybean oil was more obesogenic and diabetogenic than coconut oil and fructose.
Remember in the discussion of diabetes and seed oils, context matters. This study shares different adverse outcomes of the animals but one flaw is that they admit “While the high fructose diet (F-HFD) did not cause as much obesity or diabetes as SO-HFD, it did cause rectal prolapse and a very fatty liver, but no balloon injury. The coconut oil diet (with or without fructose) increased spleen weight while fructose in the presence of soybean oil increased kidney weight.”
Would the fatty liver have caused further illness if this study went on longer? Context matters.
What’s difficult to decipher with this study is that every group still consumed soybean oil, fructose or carbohydrates and coconut oil. Sure, the amounts differed, but we cannot determine if the health issues came from a specific quantity of soybean oil or the combination of soybean and carbs/fructose. (Consider Randle Cycle).
And while some of the groups didn’t consume fructose, they consumed higher amounts of cornstarch, and all groups consumed maltodextrin. The question begs whether corn starch and maltodextrin work similarly to fructose in the body.
I did some quick research into corn starch and the starch is a chain of glucose molecules joined together. When corn starch gets broken down into individual glucose molecules, the end product is corn syrup. One study showed no benefit of consuming corn starch over glucose and fructose.
Is this study comparing coconut oil, soybean oil and fructose in isolation? I don’t think so.
From this study, can you deduce that soybean oil causes more obesity and diabetes than fructose and coconut oil? Could the diabetes be attributed to the high amounts of corn starch given to the heavy-soybean oil-consuming rats?
It really is difficult to infer anything from this study. My takeaway would be that consuming large amounts of two energy sources, fats and carbohydrate, cause disease. Remember, all rats were ill at the end, even though they only headlined this study with obesity.
You can see the chow mix details on this page.
We have to read the studies and understand the context of these studies.
The Mixed Research Studies
There are many studies that do not follow the ideology that polyunsaturated fatty acids are harmful. Some contradict evidence that omega-6 polyunsaturated fatty acids are harmful.
Let’s take a closer look.
Sample Study 1
In the “Exacerbation of heart and liver lesions in rats by feeding of various mildly oxidized fats” study, rats were fed different fat sources and interestingly, severe lesions were found in the animals, and in this order of oil consumption:
- Corn oil (had the most severe lesions)
- Cottonseed oil
- Soybean oil
- Olive oil
- Beef fat (Tallow)
- Saturated MCTs
- Chicken fat
- Lard (had the least severe lesions)
Hmm, this doesn’t align with linoleic polyunsaturated fatty acids being the most toxic. Why is beef fat moderately high up? (I’m not demonizing beef fat, I’m just making a case against the fear-mongering of linoleic acid, in isolation.)
Here is the last sentence of the study’s abstract, “None of the results appeared to be associated with the fatty acid composition of the fats, which suggested that these long term effects may have been due to minor constituents in the individual fats.” (emphasis mine).
Sample Study 3
Another study shared that the harm of PUFAs was not demonstrated in human studies. It may be more due to single nucleotide polymorphisms (SNPs) that may influence the metabolism of PUFAs.
In the same study, no association between PUFAs and the risk for breast cancer was observed. EPA and DHA from diet and fish oil supplementation showed a reduced risk for breast cancer.
This same study shares that higher total levels of omega-6s had significant protective effects with invasive cancer of the colon. They also shared how total omega-6s were associated with a non-significant protective effect. This does not mean to go and consume seed and vegetable oils. It just means that we might be unnecessarily fearing polyunsaturated fatty acids, especially in whole food forms.
I also find it interesting that some anti-PUFA advocates believe that all polyunsaturated fatty acids are unstable yet believe cod liver oil is safe for consumption. Have they looked into vitamin A concerns?
If you take away anything from this section, it’s to read the studies and don’t believe the headlines. Context matters. (I may have to create a shirt that says that).
Omega 3 Blood Tests
Since the fear-mongering of omega 3s polyunsaturated fatty acids, I’ve done many blood prick omega-3:omega-6 tests. Most blood markers are close to normal ranges, as the body will strive for balance. Our omega-3:omega-6 consumption doesn’t reflect the same levels in our blood. We should give our bodies a bit more credit.
And the body’s desire for homeostasis goes in line with the discussion I had with Dr. Bill Harris; our cells will do the best they can to balance omega3:6 ratios until disease is imminent.
Logically this makes a lot of sense. Most Americans are obese and diabetic, yet many have decent omega-3 profiles. Americans primarily consume omega-6 oils, yet half the population does not suffer from diabetes and obesity.
Here’s one case study. This person eats only grain-fed meat, salmon, and occasionally consumes omega-3 fish oil supplements.
As Dr. Paul Mason had noted, this person indeed has higher levels of arachidonic acid (omega-6 PUFA). It’s likely because he does not have any inflammatory triggers. And while he has higher AA levels, his omega-6:omega-3 ratio is 4.7:1. The assumption is that our ancestors ate close to a 4:1 omega-6:omega-3 ratio diet, and so we should strive to eat a 4:1 omega-6:omega-3 ratio.
If you eat foods that are well-ratioed, it does not equate to the same ratios in the blood. The best example of this is canola oil. Canola oil has an omega-6:omega:3 ratio of 2:1 (that’s superb!). Considering the anti-omega-6 advocates, canola oil has a perfect ratio and should theoretically be consumed often.
Ratios are quite misleading. If you see the omega 6 levels of canola oil, they are unnaturally high per portion size.
Should We Eat Fish?
A resounding, yes. Dr. Ben Bikman and I talked about this in great detail.
The anti-PUFA advocates are also not fond of fatty fish because of the omega-3 polyunsaturated fatty acids. If you are scared of fish on a carnivore diet, where are you getting your omega-3s? (Grass-fed meats have limited omega-3s).
Foods in the most natural forms and in the most natural environments will always be ideal. But that doesn’t mean the nutrient-density aspect is that different in farmed and conventional meats. And arguably, per the USDA database, the farmed Atlantic salmon has more omega-3s than the wild Atlantic salmon counterparts.
Note: Sardines have higher uric acid levels, so you may need to limit your sardine consumption if you suffer from hyperuricemia or gout. You can take a look at my uric acid decision tree to understand this a bit better.
If you’re afraid of consuming fish because of Perfluoroalkyl substances (PFAs) in our water, sorry to break it to you but PFAs are pervasive everywhere. Watch The Devil We Know, and you’ll understand. PFAs are extremely stable human-made chemicals that repel both water and oil. They have different properties and can change the toxicity of chemicals.
PFAS are not only in our water. PFAS are in our dental floss, non-stick pans, personal care products and cosmetics, water-repellent clothing and in our soils.
Mercury is not a big concern with fatty fish. Of course, there are big headlines that Tony Robbins was mercury-poisoned by overeating fish. Let’s be clear: he was mainly eating tuna and swordfish. These fish are not the same as salmon, salmon roe and sardines.
Oftentimes mercury is in skincare, lightbulbs, thermometers, ayurvedic remedies, fungicides, seed oils and methylmercury in fish. We can breathe in mercury. If you’ve ever been exposed to a cracked CFL lightbulb, you’ve been exposed to mercury.
If you have amalgams in your mouth (the silver filling for cavities), you are exposed to slow doses of mercury every single day.
I sat down with Dr. Dom D’Agostino, and he did some self-testing by eating over five cans of sardines daily. When he tested for mercury, he had lower levels than most of his community that didn’t eat fish.
Image Source: Bretwood Higman, Ground Truth Trekking., CC BY 3.0, via Wikimedia Commons
Not all fish are safe to consume, especially fish that have consumed dinoflagellates. These fish accumulate biotoxins stored in their livers. (Yes, you can store toxins in livers). Humans that eat these particular fish risk inducing biotoxin illness.
Find fish that are lower in mercury levels but make sure to include fatty fish as it’s ideal to round out your carnivore diet. It’s not ideal to eat beef-only long term.
That’s enough. Enough that the carnivore community is fear-mongered into eating only pasture-raised beef and beef organs. We also don’t need carbohydrates for thyroid health. We don’t need to eat only pasture-raised pork and chickens. Sure, it’s ideal, but eat what you like and what you can afford.
The other day, a lady messaged me that she would no longer eat eggs because of the omega-6 content. This PUFA fear-mongering has detrimental ramifications. The fear-mongering is frankly unethical.
I would frankly be more concerned if carnivores did beef-only long term than if they ate grocery-store chicken and pork. I also noticed that the strong anti-PUFA advocates do not have a clinical practice.
Clinical data > Collecting studies to support your cause
Remove seed oils but don’t fear PUFAs. It’s grossly taken out of context. I hope you share this article with anyone that is fear-mongered to stop consuming pork, chicken, and fatty fish (and apparently, now eggs). Removing these foods is doing more harm than benefit to our well-being. (We need pork for thiamine and we need thiamine for metabolic function).
And fun fact, all blue zones, eat one meat in common: pork.
w️ith ♥ and hope for healing,
If you enjoyed this blog post, you may also enjoy these Nutrition with Judy blog posts:
- Thoughts on the Ray Peat diet
- Carnivore Beginner’s Guide (as an elimination diet)
- Meat and Climate Change
- Beyond Meat: Meat-Alternative Solution?
- Don’t Eat Just Beef on a Meat-Based Diet
- Make Meat a Priority for You and Your Children
- Carnivore Cure Bonus Bundle
- What’s in Canola Oil
- Raw vs. Pasteurized Milk and Dairy
DISCLAIMER: The content is for educational purposes only. While I am board-certified in holistic nutrition and a nutritional therapy practitioner, I am not providing medical advice. Whenever you start a new diet or protocol, always first consult with your trusted practitioner.