Twenty years ago, in July 1997, the Reformation Messenger contained an article about vegetable oils. It provided a discussion on the various vegetable oils, and making suggestions on which ones may be healthier than others. Since then, much research has been done on the various qualities of vegetable oils, and an updated article is warranted. What we now know about vegetable oils in general is more extensive in nature. And the bottom line is that most vegetable oils are unhealthy and we should avoid them as much as possible in our cooking.

Many people perceive vegetable oils to be a healthy product; after all, they are made from vegetables. Often nutritionists recommend vegetable oils as they are mostly unsaturated fats, which are considered healthier than saturated fats. However, the structure of the fatty acids in vegetable oils is something that mankind has been exposed to only very recently with the ability to take vegetables and make oils from them. And, as more research is done on vegetable oils, the consensus is that they are not healthy for us and affect our bodies in negative ways. Vegetable oils are handy to cook with, so they are used extensively. But does that mean they are good for us? And which oils are the healthiest?

All vegetable oils are made up of various types of fats, typically a combination of saturated, monounsaturated and polyunsaturated fats. Trans fats, which occur in small amounts in nature in animals, also make up a portion of many vegetable oils; however, these trans fats are not in their natural form, but are a unhealthy by-product of manufacturing. Trans fats have been found to increase the amounts of “bad” cholesterol in the body, leading to plaque in blood vessels, increasing triglycerides and causing increased inflammation in the body. Because they are so unhealthy, governments have regulated the amount of trans fats that can be used in foods. In the United States, in 2015, the FDA set a three-year time limit for the complete removal of all trans fats from processed foods.

Oils which contain mostly saturated fats include coconut oil, palm oil, and palm kernel oil. Although saturated fats from animal foods have been implicated in an increase in heart disease, plant-based saturated fats are considered healthier. Much of the saturated fats in plant-based oils can increase the “bad” cholesterol, but on the other hand they also increase the amount of “good” cholesterol. Monounsaturated fats are found in olive, peanut and canola oil. These fats have been found to reduce overall cholesterol levels, and specifically LDL or “bad” cholesterol, while increasing levels of HDL or “good” cholesterol. Polyunsaturated fats are found in soybean, corn, sunflower, and safflower oil. They reduce overall cholesterol levels, and specifically LDL or “bad” cholesterol. Included in polyunsaturated fats are the Omega-6 and Omega-3 fatty acids. Fats are vital to our body, and are needed for many of our bodily functions. Fats provide us with energy, helps our bodies grow and develop, helps the body absorb vitamins A, D, E and K, is vital for brain function, and assists in the structure of cells. Because our bodies do not produce fats, they are considered “essential” in our diet; we need to obtain these fats from out food. Some low-fat diets deprive the body of these essential nutrients and are considered unhealthy.

But, where we obtain these fats from are also vital to our health and well-being. Fats found in natural foods are the most healthy, e.g. nuts, seeds, olives, and avocados. Prior to the introduction of vegetable oils, people cooked with fats from animals, such as with lard, tallow and butter. In the early 1900s, the process of making oils from vegetables was invented, largely as a “cheap” substitute for traditional fats. The amount of vegetable oils we eat is the single biggest increase in any kind of food nutrient over the course of the 20th century. Vegetable oils were virtually non-existent before the 1900s; now they make up about 7–8% of all calories consumed by North Americans. This equates to consuming 32 kg or 70 pounds a year per person. The numbers jumped dramatically once the campaign against saturated fats and cholesterol started. Even today, despite the fact that heart disease and cancer continue to rise at an alarming rate while saturated fat consumption is down, and vegetable oil consumption is at an all-time high, people are still believing the hype and buying this very non-traditional, non-healthy food-like product.

If vegetable oils contain healthy and also necessary fats, why are they so unhealthy for us? Cooking with vegetable oils is a problem, as the use of high temperatures in cooking degrades the oil into toxic products. More than 100 dangerous products have been found in food fried in vegetable oils. So, while trans fats are being recognized as harmful and are in the process of being completely eliminated, and saturated fats are also seen as unhealthy, we are faced with the negative health effects of cooking with vegetable oils, which have been used as so-called healthy alternatives to trans fats and saturated fats. On a side note, because many vegetables oils are derived from genetically modified crops, there is also the problem of the effects of glyphosate contamination and genetic engineering.

The most commonly used vegetable oils include rapeseed (canola oil), soybean, corn, sunflower, safflower, and peanut oil. Unlike coconut oil or olive oil that can be extracted from the plant by pressing (squeezing the plant to extract the oil), these newer oils have to be extracted in very unnatural ways, which makes them highly processed.

When talking about polyunsaturated fats, we need to look at two components contained in these fats, the Omega-6 and the Omega-3 essential fatty acids. Your body needs these two types of polyunsaturated fatty acids from your diet, because your cells cannot make them themselves. Both Omega-3 and Omega-6 fatty acids play a crucial role in brain function, in normal growth and development, stimulate skin and hair growth, maintain bone health, regulate metabolism, and maintain the reproductive system. The hormones derived from Omega-6 and Omega-3 have opposite effects to each other. Omega-6 fatty acids increase inflammation to boost the immune system, assists in blood clotting, and the reproduction of cells. Omega-3s decrease these functions. Together they work hand-in-hand to provide a balance to maintain optimal health. Omega-3 fatty acids also reduce inflammation and lower your risk of cardiovascular disease. Omega-6 and Omega-3 fatty acids are necessary to create hormones, which are contained in the membranes of cells in our body. They also play a crucial role in body functions such as cell messaging, immunity and inflammation. Acute inflammation is good because it helps your body heal from an injury; however, if you have chronic inflammation all over your body, it is a bad thing. It has been shown that chronic increased inflammation contributes to various diseases such as heart disease, asthma, autoimmune diseases, arthritis, depression, cancer and diseases which lead to a degeneration of brain cells. This imbalance has also been implicated in obesity, depression, dyslexia, hyperactivity and even a tendency towards violence. In a study, a high intake of omega-6 was shown to lead to the overproduction of compounds in the body that stimulate appetite. This resulted in the animals eating more and developing obesity. Generally speaking, the hormones made from Omega-6 are pro-inflammatory and increase inflammation, whereas those made from Omega-3 are anti-inflammatory, they reduce overall inflammation in the body.

Because of its anti-inflammatory effects, there is a lot of hype about Omega-3s and how healthy they are. But what often gets neglected is the fact that it is not the amount of Omega-3 that is vital, it is more about the ratio of Omega-6 to Omega-3 fats that are critical to good health. The reason that Omega-3 gets so much attention is that the North American and European diet is very high in Omega-6, and low in Omega-3, which creates a ratio that is unhealthy.

Most vegetable oils contain very high concentrations of Omega-6 compared to Omega-3 fatty acids. But people keeping buying into labels on vegetables oils that say “a good source of Omega-3s” without realizing that they are really just making the imbalance even worse by using these oils. They may be a “good” source of Omega-3, however, the amount of Omega-6 in vegetable oils compared to the amount of Omega-3s make them unhealthy. The typical ratio of Omega-6 to Omega-3 in vegetable oils is seen in the chart below. As you can see, most polyunsaturated vegetable oils contain almost no Omega-3 fatty acids. Canola oil has been advertised as a healthy vegetable oil as it does have a 2:1 ratio of Omega-6:Omega-3, which is a healthy balance; however, as we will learn, the highly processed nature of canola oil makes it unhealthy.

As we already learned, vegetable oil consumption rose dramatically between the beginning and end of the 20th century, and this had an entirely predictable effect on the ratio of

Omega-6 to Omega-3 fats in the American diet. Between 1935 and 1939, the ratio of Omega-6 to Omega-3 fatty acids was reported to be 8:1. From 1935 to 1985, this ratio increased to 10:1 (a 23% increase). Other calculations put the ratio as high as 12:1 in 1985. Today, estimates of the ratio range from an average of 10:1 to 20:1, with a ratio as high as 25:1 in some individuals. So what are the consequences to human health of an Omega-6-Omega-3 ratio that is up to 25 times higher than it should be? They are associated with an increase in all inflammatory diseases. As well as the diseases already listed, the list of inflammatory diseases include type 2 diabetes, metabolic syndrome, irritable bowel syndrome and inflammatory bowel disease, and macular degeneration.

A ratio of Omega-6:Omega-3 of 4:1 is considered healthy, with the best being a ratio of 1:1. The body can only support a certain amount of Omega fatty acids, thus they compete for space. What this means is that the more Omega-6 fat you eat, the less Omega-3 is available to decrease overall inflammation. On the other hand, the more Omega-3 fat you eat, the less Omega-6 will be available to the tissues to produce chronic inflammation. More Omega-3 will decrease the overall inflammation in the body.

Therefore, are the polyunsaturated vegetable oils which contain both the essential fatty acids Omega-6 and Omega-3 healthy for us? Let us take a look into the popular and cheap vegetable oil known as canola, which is widely considered one of the healthiest of vegetable oils because of its healthy balance of Omega-6s and Omega-3s. Canola is actually a hybrid of the original wild rapeseed. Wild rapeseed contains large amounts of erucic acid, which is known to cause significant heart problems, so the canola plant was developed as a healthier version of rapeseed, to produce a food-grade canola oil with lower erucic acid levels. Canola oil is a Canadian invention, cheap to manufacture, and therefore many packaged and processed foods contain it. The word “canola” was derived from the combination of “Canada” and “ola,” meaning oil. It naturally has an Omega-6 to Omega-3 ratio of 2:1. This makes it one of the most healthy vegetable oils from that standpoint. Canola oil was first created in the early 1970s as a natural oil, but in 1995, Monsanto created a genetically modified (GMO) version of canola oil. As of 2005, 87% of canola grown in the U.S. was genetically modified, and by 2009, 90% of the Canadian crop was genetically engineered. Because it is a GMO crop, it is also treated with pesticides, and the herbicide Round-Up, containing high levels of glyphosate, which has recently been classified as a carcinogen (cancer-causing) by the World Health Organization. On the list of GMO oils are also soybean, corn and cottonseed.

Like most modern vegetable oils, canola oil goes through a process of refining, bleaching, degumming, colour-enhancing and deodorization to create the final product. This processing is necessary to remove the oil from the plant, which involves high temperatures, oxygenation and chemical additives including petroleum solvents such as hexane. Because canola oil is naturally high in Omega-3 fatty acids, it becomes easily rancid and foul-smelling when subjected to oxygen and high temperatures. The oil is next refined with high temperatures and sodium hydroxide to be deodorized, to mask the smell created by the chemical processing. The process of deodorization removes much of the Omega-3 fatty acids, and converts some of them to trans fats. The oil is also treated with more chemicals to improve its colour. Although canola oil has been advertised as a healthy vegetable oil due to its balanced ratio of Omega-6:Omega-3 (2:1), the amount of Omega-3 in canola oil is generally low (9% of the oil). And due to the extensive processing it must go through, it is unhealthy despite the better-than-average ratio of Omega-6 to Omega-3. Many other vegetable oil sources such as soybean, safflower, corn, sunflower, and cottonseed must be manufactured in the same way to remove undesirable trace elements in the oil, which would cause them to be odorous, bitter tasting, or dark. These oils undergo many steps beyond mere extraction to produce a bland, clear, and consistent oil, making these oils a highly unnatural processed product. These other oils also have worse ratios of Omega-6 to Omega-3, leading to more chronic inflammation and disease.

The high temperatures that are needed when using polyunsaturated vegetable oils in cooking worsen the negative effects caused by the manufacturing process needed to initially produce them. Cooking with sunflower oil and corn oil produce high concentrations of chemicals called aldehydes at levels 20 times higher than recommended by the World Health Organization; these chemicals have been linked to illnesses including cancer, dementia, and heart disease. Polyunsaturated vegetable oils are no longer considered the healthy alternative to saturated cooking fats; and, in fact, are considered even less healthy because of the chronic inflammation that is produced by their consumption. Ideally, these vegetable oils should not be part of our diet.