Avoid Seed Oils, Protect Your Body & Mind with Healthy Fats

November 26, 2024

“You are what you eat.” You have probably heard this phrase before, along with the slightly less well-known but equally important phrase “You are what you ate.”

Yes, that’s right: you’d better think twice about whether your steak was raised on grass or GMO corn, whether your chicken ate bugs or herbicide-laden grains, and whether your fish consumed worms or pieces of ground-up fish and fish farm meal. 

In this article, you’ll get to explore how what may seem like “tiny” choices—especially in the types of oils and fats you likely consume regularly—have monumental negative impacts on your cells, your energy, and even your mental performance. Processed seed oils, the kind packed into almost every shelf-stable, frozen dinner, and fried food out there, and the same oils RFK hates, are not just temporary additions to your diet. These unstable oils, lurking in everything from granola bars to salad dressings, infiltrate your cells at the most fundamental level. By embedding themselves into your cellular membranes, they kickstart a cascade of inflammation, mitochondrial mayhem, and oxidative stress, ultimately affecting everything from your physical vitality to mental sharpness, mood, and sustained energy.

You’re about to discover why choosing high-quality fats is a way bigger deal than you might think, and more importantly, how to replace the harmful oils in your diet with brain-boosting, body-fueling fats that get you operating on all cylinders. By the end of this article, you’ll have the tools and strategies to protect your biology from the inside out, with the know-how to choose the best oils, spot food label red flags, and eat smart even when dining out. And you’ll also tap into the latest research on how to minimize the damage caused by years of exposure to these “hidden hazards” with some power-packed, science-backed dietary interventions.

Prepare yourself to overhaul your relationship with fats, reclaim your cognitive edge, and seize control over the foundational components that quite literally become you.

Uncovering the Hidden Dangers: How Seed Oils Wreak Havoc on Your Body and Mind

I first understood the importance of choosing high-quality fats when I interviewed Dr. Cate Shanahan (you can check out our podcasts together here and here), the author of the books Deep Nutrition and Dark Calories, who believes that a diet high in “crappy fat,” like the vegetable oils and trans fats found in french fries, doughnuts, and most packaged foods, is far worse than a diet high in sugar. 

When Dr. Shanahan works with professional sports teams, she recommends that they switch to a diet based on bone broth, tubers, organic dairy, bone marrow, seeds, nuts, vegetables, grass-fed beef, and wild-caught fish.

Another friend of mine, Dr. Joseph Mercola (our podcast on the toxic effects of vegetable oil is an eye-opener!), reports in the journal Nutrients how intake of linoleic acid (LA) has increased dramatically worldwide, primarily due to the rising consumption of vegetable oils. While LA is considered an essential fatty acid and supports health when consumed in modest amounts, an excessive intake of LA leads to the formation of oxidized linoleic acid metabolites (OXLAMs), impairs mitochondrial function, and contributes to many chronic diseases that have become an epidemic in the twentieth century. The standard American diet packs fourteen to twenty-five times more omega-6 fatty acids than omega-3 fatty acids, with the majority of omega-6 intake coming from—you guessed it—LA.

Why is this so important? Well, you are fat. No, I don’t mean that you are fat. But you are, at a fundamental level, partially made of fat (for more information on this topic, here’s a great article).

Cells in your body have membranes responsible for allowing compounds to move in and out of the cells so they can function properly. These membranes are primarily formed from the fats you consume. This means that how flexible and permeable these membranes are depends on the quantity and, more importantly, the quality of the fats you get from your diet.

What Happens When You Consume “Crappy Fats”

If your diet is high in heavily processed oils or oils that are prone to oxidation when exposed to heat and light, such as corn, canola, safflower, peanut, or sunflower oil, or if your diet is high in trans fats from butter substitutes and baked goods, or if your fish oil supplement is rancid and exposed to too much light and heat, or if your steak is a slab from a big ol’ corn-and-grain-fed cow, then those damaged fats get incorporated into the building blocks of your cell membranes—including those of your neurons.

If you care to impress your friends at a cocktail party, you can mention HNE, which stands for 4-hydroxynonenal. HNE forms when corn oil, canola oil, and soybean oil are heated or fried, and high reactivity of HNE results in damaging effects on proteins in your body, changing their function and stability while accelerating the cellular senescence process that results in “zombie cells” and accelerated aging (check out this podcast for more information on how to flush senescent cells out of your body). 

Damaged, highly reactive fats are found in most brands of potato chips, french fries, fried packaged foods, and pretty much any other fatty food that has been (1) heated at too high a temperature for the fat to remain stable, or (2) exposed to too much pressure for the fat to retain its natural structure. 

A common example is olive oil that has been heated to above 400 degrees Fahrenheit and used for frying multiple times. Although a spicy, dense, flavonol-rich extra-virgin olive oil is great for you, olive oil that’s been exposed to high heat is not, and you may be eating damaged olive oil at high-end restaurants without even knowing it. You can also encounter olive oil that has been cut with canola oil to save money (as I discovered in my interview with Dr. Shanahan, this happens even at five-star Napa Valley restaurants!).

Your cells take these damaged fats, incorporate them into the membrane that wraps around the cell, and voilà! You have literally become what you ate: crappy, damaged fatty acids that hang around in your body not for days or weeks, but for months or even years (the half-life of LA is approximately two years)!

Check out the list below for more information on fats/oils and their smoke points, which is the temperature at which an oil or fat begins to break down, smoke, and potentially release harmful compounds.

Why I Avoid Fried Foods From the Grocery Store and Restaurants

No organ demonstrates the effect of crappy fats better than the brain. There are copious amounts of fat in neuronal membranes. These fats insulate your brain, protect it from shock, and help your nervous system maintain a healthy temperature. The transmission of electrical signals across neuron synapses also depends on fatty acids, as do neurotransmitter levels.

This is why I would rather mow through an entire bag of sugar than consume just about any fried food on the face of the planet: the sugars aren’t going to serve as the building blocks of my body.

Sure, sugar can spike my blood glucose, cause some vascular inflammation, produce gastric bloating, and create a surge of insulin. But at least I can do things to negate most of the damage and lower the sugar spike or burn the sugar away: drop and do some burpees, or go for a run, or eat some bitter melon extract, Ceylon cinnamon, or apple cider vinegar.

You simply can’t do that with bad fats: they get incorporated into your cell membranes whether you exercise or not, and there is no immediate way to undo the damage.

About the only strategy you may have at your disposal, which is handy to know if you’ve had a big night at a steakhouse, is consuming spirulina or glycine, two compounds that may help sop up the damage, but even that evidence comes from rats fed vegetable oil. So give me a choice between a stick of cotton candy and a bag of potato chips, and I’ll eat the cotton candy, hands down.

Hidden Unhealthy Oils in Common Health Foods

You would be surprised at how many “healthy” or organic foods and so-called superfoods are jam-packed with rancid, damaged oils, just like the spirulina-infused popcorn I encountered at the airport (this podcast episode of mine with “Food Babe” Vani Hari gets into the nitty gritty details of how damaging “healthy” foods can be).

Don’t be fooled by the fancy labels and certifications on the packaging: these oils have oozed into packaged foods far beyond the obvious threats like french fries, doughnuts, potato chips, and cookies.

The following is a list of nineteen common “health” foods that often contain these rancid oils.

1. Pasteurized dairy products, such as commercially produced milk, cheeses, butter, and, yes, even many organic yogurts
2. Organic packaged pasta and rice meals (the “healthy” equivalents of Rice-A-Roni and similar foods)
3. Many big-name trail mix blends, often marketed as high-protein, low-sugar trail snacks
4. Many brands of organic nut spreads, such as almond butter, cashew butter, and peanut butter
5. Store-bought bags of peanuts, almonds, cashews, and other nuts, including many of the nut mixes in the bulk food section of the grocery store
6. Baking chocolate and semisweet chocolate, often marked as organic or non-GMO
7. Many store-bought sauces, including those advertised as low-calorie
8. Gluten-free or organic cereal bars, granola bars, and many protein bars
9. Most salad dressings, even those from the organic or natural section of the grocery store
10. Many non-GMO vegetable chips, sweet potato chips, and coconut chips
11. Gluten-free and/or organic packaged pretzels, cookies, rice crackers, and multigrain crackers
12. Fried eggs at many breakfast joints, or any eggs prepared with high heat
13. Sautéed or stir-fried foods at most restaurants, including fish, vegetables, and leafy greens
14. Many dairy-free ice creams, including those made with coconut, cashew, or almond milk
15. Butter substitutes and spreadable fats like margarine
16. Premade packaged popcorn, especially cheddar-flavored and caramel popcorn
17. Both dairy and nondairy coffee creamers
18. Most popular frozen meals marketed as healthy
19. Gluten-free and/or organic frozen pizzas

The best defense? Check labels!

The role fats play in cell membranes is not the only reason to be careful with damaged fats. A consistent intake of these fats leads to chronic inflammation.

Acute inflammation is part of the body’s natural response to infection and tissue damage and is even important for muscle growth after exercise. But chronic inflammation can lead to many physiological problems, from obesity and muscle loss to atherosclerosis and arthritis. According to many nutritionists and scientific studies, sugar is the most inflammatory aspect of any diet. High sugar intake is indeed inflammatory, but it is not as terrible as consistent processed oil consumption.

Processed oils like canola or vegetable oil are polyunsaturated fats, which are molecularly unstable and prone to cell-destroying oxidation. Oxidants are reactive molecules that are used to transfer electrons from one atom to another. They are naturally produced both inside your body and the environment, but in excess they can react with other cellular molecules in your body, such as proteins, DNA, and lipids, often contributing to disease and inflammation in the process. (This is why antioxidants are so important—they help prevent oxidation-related damage.)

Should You Eat at the Whole Foods Salad Bar?

If you are the average health enthusiast who doesn’t mind paying $27 for a salad, you have undoubtedly spent time hunting and foraging at the hot bar and salad bar of a fancy, highfalutin grocery store like Whole Foods Market. Fact is, many of the prepared foods at these bars—from the marinated yams to the rotisserie chicken to the vegetarian buffalo wings—are drenched in canola oil.

Should you be worried? It depends. Not all canola oil is created equal.

Whole Foods only uses non-GMO canola oil that’s been expeller-pressed—a mechanical process that simply squeezes out the oil instead of using chemical solvents to extract it. So it is safe to say that compared to the average chemically processed, GMO canola oil, the canola oil you find in the Whole Foods salad bar is relatively healthier.

But all canola oil is still refined, partially damaged, and high in erucic acid, a fatty acid associated with heart damage, high blood pressure, and blood clotting. It also contains trans fats. All of this can deleteriously affect cholesterol levels and cardiovascular health.

While the canola oil you consume at the salad bar of a health-food store is likely healthier than the canola oil you get in a basket of french fries and a burger, you are still filling your body with a less-than-ideal fat. I advise moderation, even with non-GMO, expeller-pressed canola oil.

Finally, to limit the potential damage that seed oils like canola, sunflower, and safflower oil can cause to your cell membranes, consider the advice of Dr. James DiNicolantonio (you can check out our podcasts together here and here), author of Superfuel, who says that supplementation with 20 g of glycine (preferably split into four servings of 5 g each) and 2 to 5 g of spirulina may help mitigate the damage.

Why Do People Still Claim That Seed Oils Are “Heart Healthy”?

Should you want even more scientifically backed fodder to dialogue with your friends or family members who say seed oil danger claims are overinflated and that seed oils are “heart healthy,” check out this incredible X thread by my friend Chris Masterjohn.

I’ll sum it up for you here.

If you critically examine the prevailing research that deems seed oils safe, you will find several methodological flaws. One significant concern is the reliance on epidemiological studies, which often fail to account for confounding variables such as overall diet quality, lifestyle factors, and socioeconomic status. This oversight can lead to misleading associations between seed oil consumption and health outcomes. For many years, people were told that seed oils are “heart healthy,” and so many seed oil-consuming people who have been studied were also engaged in activities like exercise, high fruit and vegetable intake, or avoidance of junk food. This is called “healthy user bias.”

Additionally, many of these studies depend on self-reported dietary data, which is susceptible to inaccuracies and recall bias, further compromising the reliability of the findings (can YOU tell me what you ate last Sunday night for dinner?).

Another issue is the generalization of results from studies using unrefined, cold-pressed seed oils to all forms of seed oils. Most commercially available seed oils are highly processed, involving high-heat extraction and chemical treatments that can alter their chemical composition and potentially introduce harmful compounds. The health effects observed with unrefined oils used in some studies are likely not applicable to their refined counterparts, yet this distinction is often overlooked in research conclusions.

Furthermore, much of the seed oil research is funded by industries with vested interests in promoting seed oils, raising concerns about potential biases in study design and interpretation.

Perhaps most importantly many studies focus on short-term markers of health, such as cholesterol levels, without considering long-term outcomes like chronic inflammation or oxidative stress. This narrow focus can obscure potential adverse effects of seed oils that manifest over extended periods, often years! In other words, a six-week study on the effects of seed oil consumption on overall health doesn’t really tell you much at all. So, there is a huge necessity for long-term research to fully understand the health implications of seed oil consumption. Short-term studies cannot detect the gradual accumulation of lipid peroxides and other oxidative compounds resulting from the consumption of polyunsaturated fatty acids (PUFAs) found in seed oils. Over time, these compounds can contribute to the oxidative stress and inflammation you read about elsewhere in this article, potentially leading to chronic diseases. More long-term, extended studies are essential to observe these cumulative effects and provide a more comprehensive assessment of the safety of seed oils in the diet.

These factors—healthy user bias and self-reported dietary data, use of unrefined vs. refined seed oils, and freaking very short studies—collectively suggest that the current body of research does not fully capture the potential health risks associated with seed oil consumption!

How to Ditch Seed Oils and Incorporate Healthy Fats Into Your Diet

Fueling your brain and body starts with cutting out the processed, heat-damaged vegetable oils and polyunsaturated fats that disrupt cellular health. Then you have to increase your consumption of healthy fats and cholesterols from natural, whole-food sources. As Dr. Shanahan writes in Deep Nutrition: 

“A necessary outgrowth of the indictment of cholesterol is a rejection of the traditional, natural fats that have sustained humankind for thousands of generations. It’s a little like the idea that Nestle successfully used in the 1940s to sell infant formula to my grandmother and many other women, claiming it was ‘more perfect than breastmilk.’ Those who mean to replace natural, traditional foods with modern-day food-like products in the name of health are championing the position that nature doesn’t know best; a corporation does. This is an extraordinary claim requiring extraordinary evidence—a burden they have failed to meet.”

She goes on to explain that for centuries, fat has been an integral part of many ancestral diets. The ancestral Northern European diet, for instance, is high in fatty fish, red meat, and fermented full-fat dairy products, which means that if your ancestors were Northern European, you have inherited a wealth of genes that rely heavily on fats.

The same concept applies to a traditional Mediterranean diet. Sure, a Mediterranean diet includes ample carbohydrates like bread and pasta, but in coastal countries like Italy, a large part of the daily meal plan includes foods full of healthy fats, such as fish, nuts, full-fat milk, and cheeses like pecorino or mozzarella di bufala (buffalo mozzarella), along with plenty of fasting and caloric restriction (here’s more information on the diets of people who live in some of the Blue Zones mentioned above). Because your brain is composed of and uses so much fat (60 percent of your brain is fat!), a diet that is low-fat or fat-free, or that consists of inflammatory fats, can significantly damage your cognitive health.

Looking for more insights into your health and wellness? You’ll be happy to hear that I just finished updating and editing my best-selling book, Boundless. The brand new version of Boundless covers everything you could possibly want to know about optimizing your health and longevity, including how to boost your mitochondrial function, reboot your circadian rhythm, increase your libido, manage chronic conditions, enhance your mind using new smart drugs and peptides, reverse aging, improve sleep, burn fat, maintain health routines at home and while traveling, and much more!

If you’re ready to uncover a treasure trove of the latest science-backed strategies for improving every aspect of your mind, body, and spirit, you can click this link to pre-order your new updated copy of Boundless.

Additionally, if you have any questions, comments, or feedback, you can drop me a line in the comments below, and I’ll be sure to respond!

P.S. BONUS TIP: Do I EVER eat tortilla chips or potato chips? I do, but I am officially *addicted* to the uber-healthy versions made with beef tallow. The top brands I use are MASA for tortilla chips and Vandy for potato chips. You’ll thank me forever after you try them!