When it comes to a healthy diet, not all oils are created equally. The American Heart Association’s continued endorsement of vegetable oils as “heart healthy” is a manipulation of science and a violation of patient trust, all to increase the profitability of a private industry. Many people consider the American Heart Association a nonprofit public interest group.
This discussion will start with canola oil, but includes all refined, bleached, and deodorized (RBD) oils and industrial seed oils (vegetable oils).
Is Canola heart healthy?
Canola comes from “Canada” and “ola,” denoting oil. It is the second-largest oil crop in the world, and was created through crossbreeding rapeseed plants and then genetically modified (GMO) to resist herbicides in order to improve oil quality and increase plant tolerance to herbicides. It was then used to create canola oil and canola meal as well as used as a fuel alternative to diesel and a component of items made with plasticizers.
Processing canola to oil: Canola oil is a “vegetable oil” derived from the canola plant produced with high heat and exposure to chemicals, it is industrial seed oil. This industrial process is called refined, bleached, and deodorized (RBD) oils and is used for canola, soy, corn, and palm oils.
- Seed cleaning: Canola seeds are separated and cleaned to remove impurities such as plant stalks and dirt.
- Conditioning and flaking: Seeds are pre-heated to about 95℉(35℃), then “flaked” by roller mills to rupture the cell wall of the seed.
- Cooking: The seed flakes are cooked by a series of steam-heated cookers. Typically, this heating process lasts 15–20 minutes at 176–221℉(80°–105°C).
- Pressing: The cooked canola seed flakes are pressed in a series of screw presses or expellers. This action removes 50–60% of the oil from the flakes, leaving the rest to be extracted by other means.
- Solvent extraction: The remaining seed flakes, containing 18–20% oil, are further broken down using a chemical called hexane to obtain the remainder of the oil.
- Desolventizing: The hexane is then stripped from the canola meal by heating it a third time at 203–239℉(95–115°C) through steam exposure.
- Bleaching and Deodorizing: The extracted oil is refined by varying methods, such as steam distillation, exposure to phosphoric acid, and filtration through acid-activated clays.
At this point we have liquid vegetable oil, but to make it a solid, we have one additional step
- Hydrogenation: Canola oil made into margarine and shortening further processed with molecules of hydrogen pumped into the oil to change its chemical structure. This makes the oil solid at room temperature and extends shelf life but also creates artificial trans fats
Canola is not a good source of nutrients. Refining markedly decreases nutrients in oils, such as essential fatty acids, antioxidants, and vitamins
One tablespoon (15 ml) of canola oil delivers (6):
Calories: 124
Vitamin E: 12% of the Reference Daily Intake (RDI)
Vitamin K: 12% of the RDI
Fatty acid breakdown of canola oil
Saturated fat: 7%
Monounsaturated fat: 64%
Polyunsaturated fat: 28%
21% linoleic acid — more commonly known as omega-6 fatty acid
11% alpha-linolenic acid (ALA), a type of omega-3 fatty acid
Canola is no different than any of the other industrial seed oils; none of them are truly “heart healthy” and they all lead to metainflammation:
Canola oil
Soybean oil
Safflower oil
Sunflower oil
Corn Oil
Cottonseed oil
The history of industrial seed oils:
Unlike traditional fats such as olive oil, coconut oil, butter, ghee, and lard, industrial seed oils are a recent addition to the human diet, introduced into the American diet in the early 1900s.
Industrial seed oils were classified as hazardous waste products from cottonseed processing, often dumped illegally into rivers, and occasionally added illicitly to animal feed. The omega-6 fatty acids they contained rapidly oxidized in air and created a significant stench. This became an issue in the 1800s after the cotton gin was introduced, with the mass production of cotton fiber; 100 pounds of fiber processed then produced 162 pounds of cotton seeds.
In the 1870s, William Procter and James Gamble began capitalizing on this hazardous byproduct, using it for soap making and cosmetics.
Eventually, Proctor & Gamble acquired a patent to hydrogenate liquid cotton seed oil into a solid, creating a shortening-like product, called Crisco (Crystallized Cotton).
Proctor and Gamble began marketing Crisco to housewives as a lard alternative, using free cookbooks, baseless health claims, and endorsements.
Then, in the late 1940s, Procter & Gamble gave a $1.5 million donation to a small group of cardiologists who had formed the American Heart Association. The American Heart Association then endorsed industrial seed oils. To distinguish their product from animal based products and to give it an appearance of health, the term “vegetable oil” was created to use instead of industrial seed oil. Other vegetable oils followed. Soybeans were introduced to the United States in the 1930s and into the 1950s.
Around the same time, an industry-sponsored researcher, Ancel Keys, introduced the diet–lipid hypothesis, suggesting that the fat we eat becomes the fat in atherosclerotic plaques, thus causing heart attacks. The data he presented suggests a link between saturated fat and cholesterol intake and the risk of heart disease. Keys’ conclusions were in line with the industrial seed oil industry’s motives—to get people to eat more seed oils. Animal fats, a rich source of dietary saturated fat and cholesterol, were quickly ostracized. The food industry responded by increasing the marketing for vegetable oil and polyunsaturated fatty acids (PUFAs). Advertisements for “heart healthy” margarine (a solid form of vegetable oil) and other seed oils became commonplace, and traditional saturated fats were despised. The food industry and the federal government also began a campaign of reducing overall fat consumption, replacing it with manufactured carbohydrates, flavored artificially to simulate nutrient density .
Unfortunately, none of this diet-lipid hypothesis was true; the data had been purposely manipulated. A 2014 meta-analysis found no benefit to overall health from reducing saturated fats or increasing PUFAs from vegetable oils. The evidence does not support the current dietary guidelines urging people to replace saturated fats with vegetable oils. In fact, the majority of non-industry sponsored research indicates that the consumption of industrial seed oils has a significant adverse effect on health.
This also calls into question the value of statins, which lower circulating cholesterol. This cholesterol is necessary for hormone production and patients placed onto statins are much more likely to get type 2 diabetes. Many of these statins also seem to disrupt the energy production pathways in the human mitochondria as well, causing unintended secondary side effects.
The rapid oxidation of Omega 6 PUFA vegetable oils and oxidized linoleic acid seems to the common pathway for metainflammation. It is the oxidized linoleic acid, from Omega 6 PUFA vegetable oils, that is found in high concentration in the foam cells of atherosclerotic plaques. It is not the dietary saturated fats. In rat cancer models, it is very difficult to stimulate cancer formation in rats that are not first exposed to linoleic acid, which oxidizes quickly.
The conspiracy side of my brain wonders if the American Heart Association’s ongoing support of vegetable oil might not be self-serving, increasing the rates of severe cardiovascular disease, medication management with statins, and requirement for stenting procedures. It pairs nicely with the American Diabetes Associations push on diabetes type 2 not being a choice, the ever increasing cost of insulin, and the complications of diabetes.
Reasons industrial seed oils are unhealthy:
- Derived from genetically modified crops and are an evolutionary mismatch.
- Contain harmful additives and repeated heating creates toxic byproducts.
- Unstable and oxidize easily.
- Raises the omega-6-to-omega-3 fatty acid ratios.
- Derived from genetically modified crops and are an evolutionary mismatch.
- The standard American diet, high in refined carbohydrates and industrial seed oils, works against our ancestral biology, creating a mismatch between our genes and the modern environment. We have had millions of years to evolve, but unfortunately our diet has changed in less than 100 years. Our genes and metabolism simply can’t adapt fast enough. Until the 1900s, humans did not consume industrial seed oils. From 1970 to 2000, the average consumption of just soybean oil increased from four pounds per person per year to 26 pounds per person per year. Linoleic acid, the primary fatty acid in industrial seed oils, now accounts for 8 percent of our total calorie intake, yet in our hunter-gatherer ancestors, it was 1 to 3 percent of total calories consumed.
Industrial seed oils are derived from genetically modified plants. In fact, the plants used to make industrial seed oils comprise the top genetically modified crops: 88 percent of corn, 93 percent of soy, 94 percent of cotton, and 93 percent of rapeseed. Few studies have been conducted on the long-term safety of consuming genetically modified foods. These genetic modifications are done to reduce the kill ratio of the plant to herbicides, and to make the plant resistant to consumption by insects.
- Contain harmful additives and repeated heating creates toxic byproducts.
- These oils also contain harmful additives, and repeated heating creates toxic byproducts. The polyunsaturated fatty acids in industrial seed oils are so highly unstable, synthetic antioxidants are added to prevent oxidation and rancidity. Unfortunately, these synthetic antioxidants, BHA, BHT, and TBHQ, have endocrine-disrupting, carcinogenic, and immune-disrupting effects. Also, TBHQ has been found to increase the IgE (immunoglobulin E) response to food allergens, setting off a release of antibodies, and may thereby promote the development of food allergies.
Many restaurants frequently repeatedly heat industrial seed oils, a practice that magnifies the harmful effects. Reusing industrial seed oils (typically in large deep-fryers) reduces costs, but results in an oil that is full of toxic byproducts, which cause formation of free radicals, increased oxidative stress, and damage to the DNA. The repeated heating of industrial seed oils depletes vitamin E, a natural antioxidant. These effects explain why repeatedly heated industrial seed oils is associated with high blood pressure, heart disease, and intestinal and liver damage.
- Unstable and oxidize easily.
- The polyunsaturated fatty acids in industrial seed oils are highly unstable and oxidize easily upon exposure to heat, light, air and chemicals used in manufacturing. When industrial seed oils are exposed to these factors, trans fats and lipid peroxides are created. Trans fats are known for their role in cardiovascular disease and type 2 diabetes; a 2 percent increase in calories from trans fats doubles the risk of heart disease. Lipid peroxides are toxic byproducts that damage DNA, proteins, and membrane lipids throughout the body. The accumulation of lipid peroxides in the body promotes aging and the development of chronic disease.
Raises the omega-6-to-omega-3 fatty acid ratios.
Essential fatty acids are polyunsaturated fats that we cannot make ourselves and must consume in our diets. They come in two types of polyunsaturated fats: omega-6 fatty acids and omega-3 fatty acids.
Omega-6 fatty acids give rise to the arachidonic acid pathway and potent metabolites that are primarily pro-inflammatory, including prostaglandin E2 and leukotriene B4.
Omega-3 fatty acids such as ALA, EPA, and DHA, on the other hand, give rise to anti-inflammatory derivatives.
Maintaining a balance between omega-6 and omega-3 fatty acids promotes optimal health. The ancestral ratio of omega-6 to omega-3 is 1:1. The standard American diet tilts the balance to a predominant omega-6 to omega-3 ratios in the range of 10 to 1 to 20 to 1. A high intake of omega-6 fatty acids, combined with low omega-3 intake, leads to an imbalance in pro-inflammatory and anti-inflammatory mediators, producing a state of chronic inflammation called metainflammation. Industrial seed oils are the most significant contributor to the excessive omega-6-to-omega-3 ratio.
Mechanism related to disease processes:
Metabolic Inflammation (Metainflammation)
A high omega-6 intake from industrial seed oils promotes chronic systemic inflammation and is associated with elevations in C-reactive protein, TNF-alpha, and interleukin-6. Osteoarthritis is associated with elevated levels of omega-6 fatty acids in the joint synovium, the membrane that lines joint cavities. Conversely, an inverse relationship has been found between omega-3 fatty acid consumption and cartilage loss in the knee as indicated by MRI. Since industrial seed oils contribute a large amount of omega-6 fatty acids to the diet, avoiding these oils may be beneficial for those with or at risk of osteoarthritis.
Omega 6 content increased inflammation and oxidative stress
Compounds formed during the heating of canola oil increase inflammatory marker.
Chronic exposure to a canola-rich diet resulted in significant harm to memory and substantial increases in body weight. In a year-long human study, 180 older adults were randomly assigned to either a control diet rich in refined oils — including canola — or a diet which replaced all refined oils with 20–30 ml of extra virgin olive oil per day. Those in the olive oil group experienced improved brain function compared to the others.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5775590/
Metabolic syndrome is a cluster of conditions — high blood sugar, excess belly fat, high blood pressure, and high cholesterol or triglyceride levels, and is aggravated by Omega 6 industrial seed oil consumption, contrary to the industry sponsored marketing of “heart healthy.”
This 2018 study is directly contrary to industry-funded studies of canola oil intake being beneficial on heart health by decreasing cholesterol and “bad” LDL cholesterol levels.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3746113/
In another study of 458 men, those who replaced saturated fats with unsaturated vegetables oils had lower “bad” LDL cholesterol levels — but significantly higher rates of death, heart disease, and coronary artery disease than the control group.
https://www.ncbi.nlm.nih.gov/pubmed/23386268
Replacing saturated fats with vegetables oils is unlikely to reduce heart disease, death from heart disease, or overall mortality
https://www.ncbi.nlm.nih.gov/pubmed/28526025
Infertility
Approximately 9 percent of men and 11 percent of women in the United States have impaired fertility. Infertile men exhibit a significantly elevated omega-6-to-omega-3 fatty acid ratio compared to fertile men. Male impotence is also significantly associated with omega-6 industrial seed oil consumption, and the prevalence of impotence mirrors the increased consumption of industrial seed oils.
Asthma
Industrial seed oils contain pro-inflammatory omega-6 fatty acids relative to anti-inflammatory omega-3 fatty acids, which seem to dramatically increase the risk of asthma. The arachidonic acid cascade produced by omega-6 fatty acids is suppressed by steroid use in asthma attacks.
Autoimmune Disease
Industrial seed oils promote autoimmunity by increasing oxidative stress and chronic inflammation.
Cognition and Mental Health
Industrial seed oils predispose individuals to depression, anxiety, cognitive decline, and dementia. Canola oil consumption is specifically linked to worsened memory and impaired learning ability in Alzheimer’s disease. Trans fats, a consequence of chemical and heat processing of industrial seed oils, are associated with increased risks of dementia and, interestingly, aggression.
Diabetes and Obesity
Industrial seed oils increase overweight, obesity, prediabetes and type 2 diabetes. In mice, consuming high levels of linoleic acid, consistent with the standard American diet, alters neurotransmitter signaling, increasing food consumption and fat mass. In mice, a diet high in soybean oil induces obesity, insulin resistance, diabetes, and fatty liver disease. Animal research also suggests that canola oil may directly cause insulin resistance. Human studies also suggest that industrial seed oil consumption is associated with insulin resistance, prediabetes, and obesity. A maternal diet high in omega-6s compared to omega-3s is associated with an increased risk of obesity, a major risk factor for diabetes in children.
Heart Disease
Contrary to what the American Heart Association has been telling us for the last 100 years, industrial seed oils are not good for our hearts. In fact, oxidized fatty acids from industrial seed oils appear to play a pivotal role in the development of cardiovascular disease. Oxidized linoleic acid appears to be the critical link between atherosclerosis formation, and the local immune response with acute coronary plaques:
- Dietary linoleic acid from industrial seed oils is incorporated into blood lipoproteins.
- Unstable linoleic rapidly oxidizes the lipoproteins
- Oxidized lipoproteins are unable to be recognized by their respective receptors
- Activated macrophages perceive oxidized lipoproteins as foreign, and initiate foam cell formation, which causes atheroscleritis, an acute inflammatory change.
The high omega-6 to omega-3 ratio of industrial seed oils is an established risk factor for cardiovascular disease. The high omega-6 has pro-inflammatory and prothrombotic effects on the vascular system. Canola and soybean oils also inhibit vitamin K2, which clears the blood stream of excitotoxic ionized calcium.
IBS and IBD
Industrial seed oils may harm gut health, aggravating or causing irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). Mice fed a diet high in omega-6 fatty acids from corn oil experienced increases in pro-inflammatory gut bacteria. Human studies also suggest a link between industrial seed oils and GI conditions. Women with IBS demonstrate significantly elevated levels of arachidonic acid, an omega-6 fatty acid abundant in industrial seed oils, and pro-inflammatory PUFA metabolites, compared to healthy controls.
First avoid industrial seed oils.
The first step is to clean out your pantry and get rid of any bottles of canola, corn, cottonseed, soybean, sunflower, safflower, or peanut oils you have in your kitchen. These oils are not “healthy,” despite misleading claims that may appear on their labels.
Next stop eating processed foods; these are a significant source of industrial seed oils.
Reduce your consumption of restaurant foods, which are sometimes cooked in repeatedly heated industrial seed oils.
Avoid eating grain-fed meat, which may accumulate the toxic byproducts of industrial seed oils. Industrial seed oils are so good at increasing obesity, they are often added to animal feed to increase fat content and rapidly grow the animal.
When consumed as part of a balanced, real-food diet containing omega-3 fatty acids from seafood, omega-6 from whole foods is not a problem. These whole-food sources of omega-6 fatty acids include nutrients that protect omega-6 from becoming oxidized, and they are also not exposed to the chemicals and industrial treatments that make industrial seed oils so toxic.
What are safe alternatives to vegetable oil?
Alternatives to “vegetable oil” which are heat-stable:
- Olive oil: Olive oil is rich in anti-inflammatory compounds, including polyphenol antioxidants, which may prevent heart disease and mental decline.
- Coconut oil: Coconut oil is one of the best oils for high-heat cooking and may help increase “good” HDL cholesterol.
- Avocado oil: Avocado oil is heat-resistant and contains carotenoid and polyphenol antioxidants, which may benefit heart health.
Alternatives to vegetable oil which can be heated, but are not stable at high temperature:
Pastured Lard: Lard is mostly composed of monounsaturated fat, similar to olive oil. Lard, the fat rendered from pigs, is high in saturated fat and is a good substitute for butter in recipes if you can’t tolerate dairy.
Butter and Ghee: Butter and ghee from grass-fed animals contain conjugated linoleic acid, a type of fatty acid with anti-cancer and metabolic health-promoting properties. While butter may contain traces of milk proteins, ghee is usually a safe option even for dairy-sensitive people because all milk constituents are removed in its creation.
Alternatives to “vegetable oil” which are for salad dressings and other uses that don’t involve heat:
- Flaxseed oil: Flaxseed oil may help reduce blood pressure and decrease inflammation.
- Walnut oil: Walnut oil has a rich, nutty taste and has been shown to reduce high blood sugar and cholesterol levels.
- Hempseed oil: Hempseed oil is highly nutritious and has a nutty flavor perfect for topping salads.
