

Vegetable Oils Are In Almost All Of Our Food - And They’re Dangerous

Why Vegetable Oils Destroy Our Health

Vegetable oils are better termed industrial seed oils since they’re not made from vegetables and an industrial process is required to extract them. When you hear “vegetable oils”, think industrial seed oils, and understand what that means.

These industrial seed oils are made from soybeans, canola, corn, cottonseed, peanuts, sunflowers, and sesame seeds.

Olive oil and Avocado oil are often considered vegetable oils, but this is an incorrect categorization because both olives and avocados are fruits.

The History Of Industrial Seed Oils

Industrial seed oils are a relatively recent addition to the human diet. Before the advent of highways, railroads and refrigeration, industrialized America relied upon steamships moving through a system of canals, rivers and lakes to transport goods. Due to the fattiness of pigs which allowed it to be preserved with salt, pork was the predominant meat in trade at that time. One of the by-products of pork production was that pork fat was used to make soap and candles, and as a cooking fat (lard).

In the 1870s, America was facing a major economic depression. William Procter, a candlemaker, and James Gamble, a soap maker, joined forces in order to try and cut costs and survive the down market by combining forces and creating Procter & Gamble, a company that would come to be responsible for one of the greatest dietary shifts in human history.

These two enterprising entrepreneurs decided to create a new type of soap made from vegetable oils. Around this time, oil had been discovered and quickly displaced cottonseed oil as a fuel source (it had long been used for lighting). Cottonseed oil was a toxic waste product of cotton production, and Procter and Gamble realized that they could use this unwanted oil to produce soap.

Unfortunately, they also realized that the oil could be chemically altered via a process called “hydrogenation” to turn it into a solid cooking fat that resembled lard. This is how toxic waste was introduced into the American diet, with the introduction of Crisco in the early 1900's.

Soon other vegetable oils followed. Soybeans were introduced in the 1930's, and by the 1950’s it had become the most popular vegetable oil in the country. Canola, corn, and safflower oils followed shortly after that. The low cost of these cooking oils, combined with the strategic marketing on the part of the oil manufacturers, made them wildly popular despite being little more than toxic sludge.

The Process Of Making Industrial Seed Oils

The process of making industrial seed oils is very unnatural - the oils extracted must be refined, bleached, and deodorized before they are suitable for human consumption.

The seeds are heated at extremely high temperatures which causes the unsaturated fatty acids in the seeds to oxidize, making them very damaging to human cells when consumed.

Then the seeds are processed with a petroleum-based solvent, such as hexane, to maximize the amount of oil extracted from them. Other than its use for extracting the oil from seeds, hexane is used as an additive in consumer products such as gasoline, glue, varnishes and inks, as a cleaning agent, as a special glue used in roofing, and for extracting oil and grease contaminants from soil and water for analysis in laboratories.

After the oils have been extracted using hexane, the manufacturers use chemicals to deodorize the oils, as they smell really bad after the extraction process is complete. This process creates trans fats, largely considered the most harmful type of fat one can eat.

Lastly, more chemicals are added to improve the colour.

Industrial seed oil processing creates a product laden with chemicals, trans fats, and byproducts which create oxidation in the body.

How Do Industrial Seed Oils Impact Our Health?

The impact of industrial seed oils on human health is nothing short of catastrophic. The list of diseases impacted by industrial seed oils is extensive.

  • Obesity
  • Cardiovascular disease
  • Depression and other mood disorders
  • Insulin resistance and diabetes
  • Arthritis
  • Cognitive decline
  • Gut problems and gut flora dysfunction
  • Infertility
  • Macular Degeneration

What is the mechanism that leads to these diseases?

Industrial seed oils were never a part of our ancestor's diets, having only become prominent in the North American diet since their creation in the late 1800’s. Between 1970 and 2000, the average consumption of one industrial seed oil, soybean oil, skyrocketed from 4 pounds per person per year to 26 pounds per person per year.

soybean oil use

One of the biggest problems with seed oils is that they literally become part of our bodies. Unlike other food components like protein and carbohydrates which are broken down before they are burned or incorporated into the body, fats can directly become part of us (you are what you eat!). The average body has become saturated with seed oils fats, compared to just a few decades ago.


Linoleic acid

The average body contains more than double the amount of linoleic acid (the main omega-6 fatty acid) then it did just a few decades ago. Optimal health relies on a delicate balance between omega-6 and omega-3 fatty acids, with our ancestors having a ratio about omega-6 to omega-3 of about 1 to 1. Our modern diet has a balance of about 10 to 1 or 20 to 1. This imbalance creates an inflammatory environment in the body, making us susceptible to all kinds of inflammatory diseases. These are diseases of modern civilization, the scourge of highly processed foods.

Beyond the high linoleic content of industrial seed oils, there are other problems associated with their production. The polyunsaturated fatty acids in industrial seed oils are highly unstable and oxidize easily upon exposure to heat, light and chemical inputs. When industrial seed oils are exposed to these factors, two harmful substances are created - trans fats and lipid peroxides. Trans fats are well known for their role in the development of cardiovascular disease and type 2 diabetes; in fact, for every 2 percent increase in calories from trans fats, your risk of heart disease is nearly doubled! Lipid peroxides are toxic byproducts that damage DNA, proteins, and membrane lipids throughout the body. The accumulation of lipid peroxides in the body promotes ageing and the development of chronic diseases.

Industrial seed oils are also full of additives to give the fatty acids stability. These synthetic antioxidants are endocrine disrupting, carcinogenic, and immune disrupting. They also may promote the development of food allergies.

Industrial seed oils made in the United States almost all come from genetically modified plants. Very little is known about the long-term safety of consuming genetically modified foods, which should make anyone wary of ingesting them.

The Worst Way To Consume Industrial Seed Oils

By this point, it should be pretty clear that industrial seed oils are not fit for human consumption. But it gets worse.

Restaurants and even many people cooking at home will repeatedly reuse industrial seed oils over and over again. With each reuse, the oil becomes more saturated with toxic byproducts. Continually reheating these oils depletes vitamin E, while inducing the formation of free radicals that cause oxidative stress and damage DNA, proteins, and lipids throughout the body. These harmful effects explain why repeatedly heated industrial oils are associated with high blood pressure, heart disease, and intestinal and liver damage.

Unfortunately, it gets worse. In a recent study, reused and reheated seed oils were found to promote metastatic cancer in mice. The mice were either fed fresh soybean oil or “thermally abused frying oil” (TAFO). TAFO is frying oil which has been repeatedly reheated and reused. The mice fed TAFO had a “marked increase of metastatic lung tumour formation”  and a “dietary induced modulation of gene expression in the liver”.

Almost all restaurants are using these cooking oils because they are cheap and can be reused over and over again. Unfortunately, these cooking oils are not just harmful to the people eating them, but also those who are cooking with them.

In humans, being exposed to cooking oil in the kitchen is associated with double the risk of lung cancer.

Why Does Government Encourage Consumption of  Dangerous Industrial Seed Oils?

Given the proven dangers of industrial seed oils, we should expect that our respective governments would have banned their use in order to protect people’s health.

Unfortunately, the opposite is pretty much true. Despite all of the evidence that shows that saturated fat is not a cause of heart disease, this idea is still promoted amongst many government and health agencies. The government of Canada for example, promotes “vegetable oils” as a source of healthy fats, while unprocessed red meats are a source of saturated fats which are bad for our health and can raise LDL cholesterol levels.

So if promoting healthy diets (based on real evidence) is not the primary purpose of government food guidelines, who are these guides really written for?

The truth is that processed food companies make extraordinary profits on their “food products”, and are able to use these profits to influence policy decisions. A population that avoids industrial seed oils and processed foods and instead purchases natural foods from local farmers is not profitable for “Big Food”. These people will also avoid many of the chronic illnesses associated with these dangerous foods, and as such will not be dependent on pharmaceutical solutions to their health problems.

Big food

We all have a choice.

We can trust the government-corporate overlords to provide advice that is in our best interest, or we can do our own research and make our own conclusions. Our health and that of our families and community rely on us making the most informed decisions that we can.

How To Avoid Industrial Seed Oils And What To Replace Them With?

Unfortunately, due to the rampant use of seed oils in restaurants, we should limit our exposure by eating out less and instead cook our own food at home.

We also need to be wary when grocery shopping, as almost every food in a package or a box contains industrial seed oils. A good strategy to employ at grocery stores is to “shop the perimeter”, where the fresh, unprocessed foods typically reside.

Even better, farmer’s markets are growing in popularity and are both a great way to gain access to healthy foods and strengthen your local community. By opting out of the processed food paradigm and instead supporting local farmers, we can ensure that more resources stay within our local communities where they are most needed.

Stronger communities, higher quality food, and less environmental degradation are all great side effects of getting our food locally.

When it comes to consuming oils, there are essentially two categories that we should focus on. Fruit oils (extra virgin olive oils, avocado and coconut oils) and animal oils (butter, ghee, lard, and tallow).

Olive oilis rich in vitamin E and polyphenols and has a wide range of health-promoting properties. Extra virgin olive oil has a relatively low smoke point (temperature where oil becomes oxidized) making it less ideal as a cooking oil, but it makes for a great salad dressing.

Avocado oilhas the highest smoke point of any oil, making ideal for high-temperature cooking. Studies have found avocado oil benefits to include the prevention of the development of diabetes, high cholesterol, high triglyceride levels and obesity. (

Coconut oil is great for cooking at medium heat. It has many health-promoting properties - it contains medium-chain triglycerides such as lauric acid, a fatty acid that is readily used by the body for energy and has antifungal, antibacterial, and antiviral properties.

Butter and Ghee are excellent sources of healthy saturated fats. Both have anti-cancer and metabolic health-promoting properties.

Pastured Lardis fat rendered from pigs, and is high in saturated fat and is a good substitute for butter in recipes for those who can’t tolerate dairy (butter/ghee).

Pastured Tallowis fat rendered from meat other than pork, such as beef and bison. It has a high smoke point making it great for cooking. Prior to the 1970’s, tallow was commonly used in restaurants for deep fryer cooking.

Bacon Greaseis my personal favourite for cooking. I simply save up the leftover bacon grease from cooking bacon and use it as needed. Bacon is a health food, rich in B vitamins, zinc, selenium, and choline. 

If optimal health is your goal, there is no room for the consumption of seed oils. That being said, the occasional consumption of seed oils may be unavoidable given how prevalent their use is in restaurants. At the very least, we can take control of our health at home by focusing on consuming healthy fats and avoiding Frankenfoods such as those that contain industrial seed oils.

Special thanks to P.D. Mangan of Rogue Health and Fitness, a great resource for true health information ( Chris Kresser's article entitled "How Industrial Seed Oils Are Making Us Sick" is a great resource for understanding seed oils, and was very influential in this article.

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