The Hidden Health Effects Of Seed Oils: What You Need To Know
Salad dressings. Granola bars. Crackers. Margarine. Chips. Cereal. Ketchup. Deli meats. Fried foods. Protein bars. Frozen lunches. Peanut butter. Popcorn. Bread.
Seed oils are everywhere.
While that’s good news for food manufacturers and grocery stores who can keep their foods more shelf stable at a cheaper price, it raises concerns about the dangers it poses to our health. In this article, we will delve into the hidden health effects of seed oils, shedding light on their impact on inflammation, oxidative stress, lipid profiles, and overall well-being.
Source: www.shefinds.com
The Corrupt Origins Of Seed Oils
For much of history, the cooking medium of choice tended to be what was naturally available. In many places, it was butter, lard, and ghee and in others, it was coconut oil, olive oil, and nut oils.
Then around the turn of the 20th century came a German chemist, Edwin Kayser, who changed everything. He had a patent to his name for the hydrogenation process of cottonseed oil. Initially, this was used to make soap and candles but William Procter and James Gamble saw a more profitable route. In 1911 they created Cristo (derived from “crystallized cottonseed oil”). Procter & Gamble enlisted the help of an advertising firm to promote their product as a healthy alternative to traditional cooking fats. They initiated a campaign to portray saturated fats as harmful to heart health and promoted Crisco as a healthier alternative.
As part of their marketing strategy, Procter & Gamble donated 1.5 million dollars for an endorsement by the AHA (American Health Association), which had previously condemned saturated fats according to The Big Fat Surprise. The AHA then advised the public to limit their intake of saturated fats and cholesterol by adopting “vegetable oils” over animal fats in an effort to reduce heart disease rates.
This endorsement by the AHA further strengthened the association between seed oils and heart health and as a result, the consumption of seed oils, particularly hydrogenated oils, increased dramatically during that time.
Then in 1958, the researcher Ancel Keys came up with the “diet-lipid” theory based on the Seven Countries Study where he cherry-picked data to support his theory that polyunsaturated fats (PUFAs) are healthy. This “research” only strengthened the claim which was further propagated by various trends including the 90’s low fat era where butter was canceled and margarine was in. Incredibly, it wasn’t until recently, over 100 years later, that we’re learning that we were bamboozled and everyone’s health suffered as a result.
Popular Science wrote, “What was garbage in 1860 was fertilizer in 1870, cattle feed in 1880, and table food and many things else in 1890.” Over 100 years later most people believe that food scientists can outsmart nature through over-processing and chemical substitutions such as margarine.
Source: www.zeroacre.com
What Are Seed Oils and Vegetable Oils?
While vegetable oils and seed oils are often used interchangeably, they are technically two different things. Vegetable oils are any fats or oils that come from various plant sources such as nuts, fruits, grains, and seeds. “Vegetable” oil, therefore, is a great marketing strategy but a bit of a misnomer since it doesn’t exclusively refer to vegetables in the culinary sense (e.g. carrots, broccoli).
Seed oils, a.k.a. industrial seed oils, are a type of vegetable oil that comes from seeds. Vegetable oils can be obtained through mechanical pressing, solvent extraction, or a combination of both methods. These oils tend to contain moderate to high levels of linoleic acid.
Common sources of seed oils, referred to as the hateful eight:
Soy & Soybean
Canola
Sunflower
Cottonseed
Safflower
Corn
Grapeseed
Rice bran
How Seed Oils Are Made
Vegetable oils, including seed oils, are typically made through a multi-step process that involves extraction, refining, and sometimes hydrogenation. While the specific methods can vary, here is a general overview of how vegetable oils are commonly made:
Extraction: Seeds or other plant parts containing oil are crushed or pressed to extract the oil. The extraction methods can include mechanical pressing, solvent extraction, or a combination of both. Mechanical pressing involves applying pressure to the seeds or plant material to squeeze out the oil. Solvent extraction involves using chemical solvents, such as hexane, to dissolve and extract the oil from the plant material.
Refining: After extraction, the crude oil undergoes refining processes to remove impurities, improve stability, and enhance the appearance and flavor. Refining techniques may include degumming, neutralization, bleaching, and deodorization. Degumming involves removing gums and other impurities through processes like water or acid treatment. Neutralization aims to remove free fatty acids by treating the oil with an alkali solution. Bleaching uses activated clays or other materials to remove color pigments and impurities. Deodorization involves heating the oil at high temperatures to remove odors and unwanted flavors. It’s as gross and unnatural as it sounds.
Hydrogenation: Some vegetable oils, particularly seed oils, may undergo hydrogenation to increase their stability and solidify the oil for specific applications, such as creating margarine or shortening. Hydrogenation involves exposing the oil to hydrogen gas under high pressure and temperature, resulting in the conversion of some unsaturated fats into trans fats and saturated fats.
Why Are Seed Oils So Unhealthy?
One of the main purposes of vegetable oils is to make processed foods more shelf stable. In a world where 70% of the average American’s diet is processed food, this is extremely important. Americans consume 5-10 tablespoons of vegetable oil every day. When trans fats were forced out of foods it was seed oils that quickly took their place, making them extremely common in today’s packaged foods.
While the process that these oils go through does not negatively impact their ability to keep food on store shelves, it does have a significant impact on our health. In addition to the amount of seed oils we consume, it is also through the widespread use of the processing of seed oils (extraction, refining, hydrogenation) where these oils turn toxic. This process involves high temperatures, chemical solvents, and additives, which result in the loss of beneficial compounds, such as antioxidants and vitamins, and the common introduction of oxidation and harmful substances.
Through the increased quantity of consumption and the poor quality of these oils, inflammation results. This inflammation occurs because of:
Oxidative stress and free radicals.
There are three types of fats: saturated (no double bonds), monounsaturated (one double bond), and polyunsaturated (two or more double bonds). Seed oils are rich in the latter, polyunsaturated (PUFAs) which are less stable due to more double bonds. This makes them highly susceptible to oxidation and a source of oxidative stress in the body. When exposed to heat, light, and oxygen (through processing, storage, and cooking) the PUFAs in seed oils can undergo oxidation, resulting in the production of harmful free radicals. These free radicals are highly reactive molecules that can initiate chain reactions, damaging cellular structures and biomolecules such as proteins, DNA, and lipids. Over time, research has shown that this oxidative instability and damage can contribute to the development of chronic diseases, including cardiovascular conditions, neurodegenerative disorders, and certain types of cancer.
Omega-6 to Omega-3 imbalance
Many seed oils are high in omega-6 fatty acids. Omega-6 is necessary in the body and while humans have eaten omega-6-containing foods like sunflowers, fish, and flaxseeds, the ratio at which we are consuming these has increased from a steady balance for most of human existence. In the last 100-120 years we have increased our omega-6 intake to the point where 20% of our diet consists of these fatty acids. Humans evolved to have a natural omega-6 to omega-3 ratio of 1:1 whereas today that ratio is around 20:1! This evolutionary mismatch and the inability of the body to handle this sudden excess in consumption leads to the conversion of these omega-6 into pro-inflammatory compounds and thus, various inflammatory-based conditions such as diabetes, stroke, arthritis, and cancer. Researchers continue to find associations of high omega-6 rations and other behavioral concerns such as suicide and depression in pregnant women and violence such as homicide.
Chemical additives
The industrial extraction and refining processes employed in producing seed oils can be a cause for concern. Many seed oils undergo extraction using chemical solvents, such as hexane, which can leave residues in the final product. These residues may include harmful substances that can have detrimental effects on health including central nervous system (CNS) damage. Hydrogenation, a common technique used to enhance the stability of seed oils and extend their shelf life, can result in the formation of trans fats. Trans fats are known to increase the risk of cardiovascular diseases, raise LDL cholesterol levels, and promote inflammation within the body. Additionally, the use of chemical additives, preservatives, and antioxidants in seed oils--which are intended to improve the oil's stability and prolong its shelf life--can have long-term health implications.
While this inflammation occurs in a variety of ways, it can impact many different areas of the body such as the brain, the heart, and the endocrine system leading to a host of health conditions.
How Seed Oils Affect Our Body
The danger of seed oils extends to our hearts, our brains, our waist lines, our moods, and more.
Coronary Heart Disease
Consuming seed oils has been shown to have a clear influence on our heart health. In 2013, researchers published data on the Sydney Diet-Heart Study. They divided participants into two groups. Each group ate the same amount of fat and oil but the difference was that the experimental group’s fats and oils came from seed oils like margarine and safflower oil. Researchers followed these groups for the next seven years. The results?
The experimental group that ate the seed oils had a rate of death 62% higher compared to the control group that ate less seed oil. This means that consuming seed oils has a higher likelihood of causing death than physical inactivity, heavy drinking, and excessive sugar consumption.
Source: www.zeroacre.com
In another study called the Minnesota Coronary Experiment, researchers uncovered documents that were in a basement for four decades. The participants, who were all institutionalized, were divided into two groups. One group was fed foods that were high in saturated fats (milk, beef, cheese, etc.) and the other group’s saturated fat intake was replaced with corn oil. The results?
“Participants who ate a diet low in saturated fat and enriched with corn oil reduced their cholesterol by an average of 14 percent, compared with a change of just 1 percent in the control group. But the low-saturated fat diet did not reduce mortality. In fact, the study found that the greater the drop in cholesterol, the higher the risk of death during the trial.”
The authors wrote that the results "add to growing evidence that incomplete publication has contributed to overestimation of the benefits of replacing saturated fat with vegetable oils rich in linoleic acid." This data runs counter to the government’s dietary guidelines, as well as counter to the author’s bias, which is thought to be the reason it was never published. Interestingly, the author’s son found the data and handed it over to be published (learn more about that interesting story here).
Brain Health
In a 2017 animal study, researchers looked at how seed oils affect brain health, specifically Alzheimer's Disease. They gave one group standard food and the other group food that had canola oil added to it for a period of six months. The results showed that the group eating the food with canola oil had significant impairments in working memory and brain structure as well as increases in body weight and beta-amyloid plaque.
The researchers concluded, "Our data would not justify the increasing tendency of replacing olive oil with canola oil as part of a good and healthy dietary alternative in non-Mediterranean countries."
Obesity
Seed oils also influence how much you weigh. A 1993 study compared rats who ate high amounts of safflower oil, olive oil, and tallow to one another. The group that ate the seed oils (safflower) gained 16% more weight than the olive oil group and 36% more than the tallow group despite eating the same amount of calories.
Another study published in 2017 divided rats into four groups (low-fat or three versions of high-fat diets comprising of 1%, 15%, or 22.5% of linoleic acid). After 12 weeks, the mice with the highest level of linoleic acid had more insulin resistance, lower activity levels, and more weight gain.
Source: https://drcate.com
Cholesterol
The consumption of seed oils can have adverse effects on lipid profiles, particularly cholesterol levels. Studies have shown that seed oils can contribute to an increase in LDL cholesterol which is a significant risk factor for heart disease. Elevated levels of LDL cholesterol can lead to the formation of plaque in the arteries, impairing blood flow and potentially resulting in heart attacks or strokes.
Seed oils have also been associated with the oxidation of LDL cholesterol. When LDL cholesterol undergoes oxidation, it becomes more likely to contribute to the development of atherosclerosis, a condition characterized by the accumulation of plaque in the arterial walls. This process promotes inflammation and can further increase the risk of cardiovascular problems.
Depression
A 2007 study looked at the relationship between omega-6 intake in adults and depression. After taking blood samples from all of the adults (averaging 66 years old), researchers found that a higher omega-6 to omega-3 ratio was associated with progressively elevated levels of inflammation as depressive symptoms increased.
Researchers then looked to determine how much of these symptoms were due to diet so they turned to different subjects: monkeys. They gave monkeys a Western Diet for 27 straight months to see what would happen to their mood. They found that “Monkeys consuming the Western diet exhibited a broad range of percent time spent in depressive behavior.” When looking at their blood levels, researchers found that, despite being leaner, the monkeys that were depressed had higher levels of PUFAs and omega-6 PUFAs.
Seed Oils and Kids
These seed oils have obvious impacts on our overall health but how do they impact children? Since doing these types of studies on children raises ethical questions, researchers went to piglets "as a model of early infant nutrition" to provide answers. Their study divided them into two groups: piglets eating a small amount of linoleic acid to prevent deficiency (1.2% of calories) and another group with a high amount (10.7% of calories, about our current human intake). The group who ate the small amount of linoleic acid had normal and healthy neurological development while the group who ate the higher levels of linoleic acid had abnormal brain development.
How To Minimize Seed Oil Consumption
Limit processed foods.
Read food labels. Avoid foods that have seed oils in the ingredients.
Use high-quality extra virgin olive oil (EVOO), avocado oil, and coconut oil for cooking.
Throw out commonly used household seed oils such as margarine, vegetable oil, salad dressings, and condiments that contain these oils.
I’ve found Primal Kitchen to be a reputable brand of condiments and oils without the seed oils (use the promo code MINDBODYDAD for a 10% discount).
Since restaurants tend to use these seed oils with cooking, limit these foods and cook at home more often.
When you do eat food from a restaurant, ask that the food be cooked in butter and not oil and limit fried food.
Increase your intake of omega-3 fatty acids (e.g. fish, walnuts, chia seeds, avocado, eggs) and consider supplementing with high-quality fish oil.
Test your Omega-3 and Omega-6 ratio. Want to know how close to that idea 1:1 ratio you are? One option is to talk to your doctor, another is to buy a certified kit from Amazon.
Beware Of The Restaurants
Restaurants are known to use high amounts of seed oils in their cooking, especially when frying foods. Oils are important in the restaurant business and going cheap is the best way to avoid an impact on the restaurant’s already thin bottom line but it's the customer who suffers.
In an ideal world, the oil used for frying foods in restaurants would be changed regularly but this takes time and money. When restaurants use their oil more than about three times then it turns into a big chemistry experiment. It creates advanced glycation end products (AGE), lipid peroxidation, aldehydes, and sometimes even trans fats and bacterial contamination.
What I Do
At home, we limit our oils to EVOO, avocado oil, butter, and the occasional coconut oil. We do plenty of home cooking, limit packaged foods in the house, and, when we are eating anything that's been processed and packaged we're quick to read labels. Even though there has been a huge uptick in "healthy" foods found in supermarkets recently, the danger of seed oils in the eye of the public tends to fly under the radar compared to more well-known threats like sugar, gluten, and artificial dyes. I'm a little jaded as a result and never surprised when I see the "healthy" alternatives laden with these oils.
On the rare times when I'm out to eat at a restaurant (or getting takeout), I try to remember to ask for my food cooked in butter instead to avoid exposure to seed oils. Since the rest of my diet and overall health is relatively clean I don't freak out if I ate something with some soybean oil.
From a parenting perspective, things get trickier. While the vast majority of our kid's diet consists of whole foods, there's no denying the convenience of packaged foods for lunches, car rides, and outings. Since even the "healthy" go-tos have oils high up on the ingredient list we scan the ingredient lists and stick with the limited diamonds in the rough. Some of these include:
I’m also cognizant of getting enough omega-3’s in my diet, often in the form of fish (salmon, sardines, tuna, etc.), eggs, seeds (flax, chia), spinach, and a high-quality fish oil.
Summary
Seed oils—such as soy, canola, sunflower, cottonseed, safflower, corn, grapeseed, and rice brain—are a common ingredient found in packaged foods yet many people are unaware of the effect of seed oils on our health. The use of these seed oils originated in the early 20th century when marketing campaigns promoted them as a healthy alternative to traditional cooking fats. These campaigns, backed by endorsements from organizations like the American Heart Association, led to increased consumption of seed oils, however, recent research has revealed that seed oils can have significant downsides to your health.
Seed oils are often produced through processes involving high temperatures, chemical solvents, and additives, resulting in the loss of beneficial compounds and the introduction of harmful substances. Seed oils are rich in polyunsaturated fats (PUFAs), which are prone to oxidation and can generate harmful free radicals in the body, leading to inflammation and oxidative stress. Moreover, the now-common high omega-6 to omega-3 ratio in seed oils can contribute to various inflammatory conditions and health issues.
Chris Masterjohn, PhD. sums it up like this:
You have to consider that PUFAs from seed oils are an oxidative liability under conditions of oxidative stress. They may not cause you harm right now but you can spend years increasing The saturation of your tissues with PUFAs by eating a high PUFA diet and the chickens may come home to roost at the end of the day...."
Studies have shown that seed oils can increase the risk of coronary heart disease, raise LDL cholesterol levels, and promote the oxidation of LDL cholesterol, which can lead to the development of atherosclerosis. These oils have also been associated with cognitive impairments, obesity, and abnormal brain development in children. To minimize seed oil intake, limit processed foods, read food labels to avoid products containing seed oils, use healthier cooking oils like extra virgin olive oil, and increase the consumption of omega-3 fatty acids.
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