- In recent years, fear of toxic and inflammatory ‘seed oil’ has taken over the internet.
- Many experts reject this and say research shows that cooking with vegetable oil is good for you.
- What seed oil actually does in our diet is more complicated than either side lets on.
In recent years there has been a war going on over the fats we eat. In concrete terms, it is a battle over ‘seed oils’. Are they as toxic as some health influencers think?
Robert F. Kennedy Jr., chosen by President-elect Trump as Secretary of Health and Human Services, is a leading figure in the fight. He has dedicated a series of T-shirts, bumper stickers and red hats to “making frying oil tallow again,” advocating for places like McDonalds to start using beef tallow again.
Nutritionists say the discourse surrounding so-called seed oils stokes unnecessary fear, obscuring the truth about what is already well known about how to eat to promote human health and longevity.
Professor Richard Bazinet, who studies how fat fuels our brains at the University of Toronto, says online discourse about seed oil as “the root of all evil” has exploded since 2020.
“People come out and say, ‘Hey, the government is lying to you,'” he told Business Insider. “Saturated fats are good for you. Seed oils are actually what kills you and causes cancer.”
Let’s not get it twisted: butter is not the salve here. But the health benefits of seed oils are also obscure.
The seed oils under fire, also known as ‘the hateful 8’
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For centuries, people around the world have used local oils, some of which could be classified as ‘seed oils’, derived from mustard seeds and flax seeds. None of them were bad for their health.
Today, “seed oil” is more of a pejorative term than a technical definition, referring to oils high in omega-6 fatty acids, including:
- Rapeseed
- Corn
- Soy
- Cottonseed
- Grape seed
- Sunflower
- Safflower
- Rice bran
Some influencers call them “the hateful eight.”
Do seed oils cause inflammation?
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Opponents of seed oils say they are toxic and often recommend butter instead, which is rich in saturated fatty acids with only small amounts of omega-6.
Cardiologist Dariush Mozaffarian, director of the Food is Medicine Institute at Tufts University, told BI that he has found no convincing evidence that seed oils are harmful.
Mozaffarian has authored dozens of studies that independently examine how oils rich in omega-6 affect health problems such as heart disease, stroke and weight gain. He said he has found a lot of evidence that they are good for overall health, lowering the rate of type 2 diabetes and improving cholesterol levels.
But he still can’t convince some of his “very smart” friends to agree with him on this, including some nutrition scientists who say the worrying trends associated with omega-6 can’t be dismissed.
A long-term study in Eastern European countries from the 1990s found that those who used ‘seed oils’ with a higher concentration of omega-3 had fewer deaths from cardiovascular disease than countries that used oil richer in omega-6.
One thing all researchers – including Mozaffarian – agree on is that we need a healthy balance between the two essential fatty acids: omega-3 and omega-6. Nowadays we don’t get enough omega-3.
There are clear trends showing that less omega-3 and more omega-6 in the diet is associated with more obesity, acting on pathways in the brain that can encourage more eating and tell the gut to store more fat. Studies link high omega-6 intake to more chronic pain, overeating and potential mood problems, while new research on omega-3 suggests supplementation may improve satiety and keep cognitive function strong in old age.
Several scientists who have studied dietary fats at the National Institutes of Health told BI that the Internet’s focus on specific oils obscures a deeper problem: omega-6 is absorbed into the U.S. food system in countless ways, disrupting the nutrient density of what we eat .
From processed foods at the gas station to seemingly harmless, seed-oil-free products like chicken eggs, our nutritional equation has been thrown completely out of balance.
Baked into the fabric of the modern American diet
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A century ago, consumption of omega-6 fatty acids amounted to less than 3% of our total calories.
That changed after World War II, when new technology made it possible to mass-produce new types of monounsaturated vegetable oils from plants rich in omega-6.
Canada invented canola, and many chefs have traded dangerous trans fats for this cheaper, more accessible oil. Food manufacturers also started making ultra-processed foods using things like canola oil or corn oil.
Suddenly, our modern dining era was born. There were some obstacles: McDonald’s only stopped using beef tallow around 1990, but as vegetarianism and veganism became more popular, ‘seed’ oils became the standard harmless, dirt-cheap choice for producing, frying and cooking food for the masses. .
Today, omega-6 is responsible for about 10% to 20% of the calories in the average American diet, which relies on the backbone of soy and corn.
It is unavoidable in our food system and is found in prepared foods in higher concentrations than ever. It’s in everything: corn chips, peanut butter, farmed salmon, even today’s grilled chicken contains more omega-6 than it used to.
It would be quite a challenge to get enough omega-3 to balance it all out.
“There is a river of oils flowing through the food supply,” said psychiatrist and nutritional neuroscientist Joseph Hibbeln.
Hibbeln is an expert in lipid biochemistry and brain health, having studied dietary fat at the National Institutes of Health for nearly three decades. Through his research, he has seen how these oils increase appetite and change people’s taste preferences, helping food companies increase sales. “It doesn’t have to be a conspiracy, it’s just: you sell more food.”
Traditional Mediterranean diets, the diet of choice for most dietitians and nutrition enthusiasts, typically had a ratio of about 1:1 between omega-3 and omega-6. There was plenty of olive oil, rich in omega-9, but also a good amount of omega-3 fatty acids from foods such as oily fish, walnuts and linseed.
Still, says Dr. Artemis Simopoulos, former chairman of the National Institutes of Health’s Nutrition Coordinating Committee, that demonizing “seed oils” misses the point. If most of your diet is ultra-processed, it doesn’t matter what your McDonald’s fries are cooked in.
“This was a problem caused by the agriculture and food industry,” Simopoulos told Business Insider.
This isn’t much different from Mozaffarian’s common refrain when someone asks him whether he should switch to avocado oil or beef tallow to avoid inflammation.
“There are things that are much more important to you than even thinking about seed oils,” Mozaffarian said. “I want people to avoid super-processed foods and avoid refined flours and sugars.”
What does this mean for the food industry?
Canola oil producers have changed the composition of their product, replacing more omega-6 with omega-9. Stuart Walmsley/Getty Images
New alternatives to deep fryer ‘seed oils’ are emerging and gaining traction.
Take Zero Acre, an oil company that develops monounsaturated oils made from fermented sugar cane. The company has investments from Chipotle, is used in the restaurants of celebrity chefs and had a partnership with Shake Shack.
The oil industry is already preparing for a change in public sentiment, and not just with independent alternatives like Zero Acre.
Simopoulos has consulted with major food companies like Nestlé and is working with farmers in China to plant more traditional camellia trees for cooking oil, which is rich in omega-3. She and Bazinet, a researcher at the University of Toronto, both said major food giants are moving away from using omega-6 heavy oils and favoring omega-9, which is nonessential and does not compete with omega-3.
“Things are completely changing, and the sooner the better,” she said.
Don’t let the fear of “seed oil” derail a healthy diet
Mediterranean diets, rich in whole grains, vegetables and olive oil, are a favorite eating plan of nutrition enthusiasts. vaaseenaa/Getty Images
American health authorities talk about nutrition in broad terms, without delving too deeply into the chemical and molecular differences between different fat sources.
They don’t make any scientific distinction between seed oils and other sources of unsaturated fat, and they don’t talk much about the importance of balancing essential fatty acids. Their relentless focus is on prioritizing “healthy fats” in the American diet, such as omega-3 from salmon, and cutting out butter, which has been linked to heart disease.
This general message is not sitting well with seed oil skeptics, who distrust the health care system and are looking for clarity on how manufactured foods affect our health. It leaves no room to acknowledge that vegetable oil may not be the best ingredient out there.
Bazinet said that while the jury is still out on seed oils, some people may want to take extra precautions. Smokers, who are already under additional inflammatory stress, may be at increased risk of health problems from consuming seed oils because their blood does not have as much capacity to oxidize fats.
For most people, the same advice you’ve heard for decades applies.
Eat a diet rich in whole grains, nuts and vegetables. These polyphenol powerhouses are dream nutrients for your body. Prioritize olive oil; this is low in omega-6, but high in non-essential omega-9, and is excellent for inflammation and brain health. Routinely include foods rich in omega-3, such as chia seeds, flax or oily fish.
Because here’s the thing: If you avoid processed foods that are packed with sugar and calories and, yes, probably contain seed oil, all nutritionists would consider that a win.