Canola Oil Real or Imagined, Fred Pescatore, MD, MPH, CCN author of The Hampton’s Diet explains how canola oil came about, why it is so popular and why we should avoid it, as he helps us learn about The Science of Fats, Fatty Acids and Edible Oils
Can-ugly Oil my pet name for canola oil. Since canola is a completely contrived substance, I thought it should have an equally ridiculous name. The patient who first turned me off of canola oil lost 58 pounds following the Hamptons diet. Trevor was thrilled to finally discover a diet that emphasized high levels of monounsaturated fats, good saturated fats and downplayed the seemingly glorified horror that is canola oil. He is a 67 year old man who worked for a major pharmaceutical company for his entire career as a chemist. He understands the chemistry of the fats much more intimately than I do; still, we came to the same conclusion. He wanted to lose weight but was having difficulty following a low carbohydrate diet approach that did not emphasize the good, healthy fats. Trevor had a heart attack four months prior to seeing me and he did not want to take any cholesterol lowering medications and was looking for a way to avoid that, if possible. He was so relieved on discovering my approach that he even helped me out with some of the chemistry you see in this book. He was a model patient and lost his weight in 6 months. His cholesterol dropped to the 170’s with his HDL level staying in the low 70’s and triglycerides in the 40’s. I will try to relate to you what he told me about the rape seed.
Can-ugly oil is derived from the rape seed which is a member of the mustard family, which also includes broccoli, kale, cabbage and mustard greens. Rape seed oil has been used in traditional Asian and South Asian cooking for many years, without cause for alarm. This is probably because the oil was processed at very low temperatures usually by hand. A study raised concerns about heart disease and its relationship to one of the fatty acids that was most prevalent in rape seed oil, erucic acid. Since that was determined, the rape seed that is used today to make canola oil was bred to eliminate virtually all of the erucic acid so that now instead of 45% erucic acid that you get from a traditional rape seed, there is generally less than 25% found in common canola oil.
Canola oil is named for a Canadian scientist who developed it, hence, Canadian oil or canola. This new rape seed was bred to have a fatty acid profile of 57% monounsaturated fat; 5% saturated fat; 24% omega-6 fat and 10% omega-3 fatty acids. Because there is a decent level of omega-3 fatty acids, it is not recommended that canola oil be heated above 120F or trans fats are formed. Considering the profile, canola oil looks like a decent product. However, there are some canola oils whose smoke point is 520 F – how did that happen? That is all from chemical manipulation of the chemical structure of the oil through refinement and processing. So, although there is a 2:1 ratio of omega-6 to omega-3 fatty acids, unless canola oil is used cold, and even then there is controversy, it is of little use and the levels of trans fats are extremely high at 4.5%, more so than margarine.
Traditionally rape seed oil was probably okay due to its gentle processing technique. However, modern canola oil processing is far from gentle and is what is responsible for making it can-ugly. The oil is removed from the seed by a combination of high temperature mechanical pressing and solvent extraction. As you will recall, traces of the solvent usually remains in the oil. Then, the oil is further refined, bleached and degummed, each step requiring exposure to high temperatures and chemicals. Since canola oil has a large amount of omega-3 fatty acids, these easily become rancid and foul smelling during these high heat processes. It therefore has to undergo another refining process called deodorization. This deodorization process removes a large portion of the omega-3 fatty acids by turning them into trans fats – which can be as high as 4.5%.
Now, canola oil is one of the most commonly used oils in processed foods. Since this oil has already been damaged by its refining process, it then undergoes another process that I have already described called hydrogenation, which further increases the trans fatty acid content of a given food. Canola oil is preferred in the processed food industry not only because it is cheap but because it hydrogenates better than soy or corn oil – an important component for shelf life stability, but not human health.
Canola Oil Mythology
In order to understand how canola oil came from not even existing on the planet to being one of the most commonly consumed oils in the American diet, we really don’t have to go back too far – only to the 1980’s. At that time, polyunsaturated fats ruled the roost and were the oils that were promoted as heart healthy. Science, however, was beginning to understand that the polyunsaturated stand was unhealthy. The powers that be could also not go back to a position that saturated fats were healthy again after they spent the better part of a decade or longer telling us that the thought of them would kill us. This was the birth of the reign of the monounsaturated fats. But, like most things governmental, the message got misguided and distorted by the food processing industry to give us what they can make the most money on. It is only now with the birth of the reign of MacNut oil and the success of the Hamptons diet can monounsaturated fats finally find a good home and be the bearer of the health message that they should.
In the mid-1980’s, articles on the benefits of olive oil, a natural monounsaturated fat, began to appear in the press. Consumers latched onto this as it seemed natural and the images of the Mediterranean and Tuscany seemed fitting for a healthy lifestyle. However, because of its expense, there had to be a cheaper alternative to use in processed foods; and, because of its relative scarcity, there needed to be an alternative. Another thing to note is that olives do not grow that well in the US as there are not that many areas of the country that have a Mediterranean-type climate. But, rape seeds are perfectly suited to growing in the US and thus became the darling of the USDA. So, that’s when a Canadian scientist developed a rape seed that was high in oleic acid and low in erucic acid, the poisonous substance – hence, the birth of LEAR (low erucic acid rape seed) or what is now known as canola oil.
This term canola oil did not come into widespread use until the 1990’s; although it was coined earlier than this. Since canola oil was a food product that was totally new; and the marketers wished to get it into the marketplace right away, it needed to be granted GRAS (generally recognized as safe) status. Otherwise, it would not be allowed into the United States food supply, nor sold as food or used in the food processing industry. Without research and testing on the product, which is normally required fro many years, this as yet untested food product was granted GRAS status by the USDA in 1985.
It is interesting to note that Stevia, a non-caloric safe and natural sweetener with no friends in the food processing industry was never granted this same status although it is not a new, man-made contrived substance, nor is it a new food product, having been used for may years without any reported problems by many other countries besides the United States. Unfortunately, Stevia is only allowed to be sold as a nutritional supplement and not as a food. The interest of big business is always at stake, even in our food supply.
Thus, the marketing of canola oil as a health food began in earnest. The marketing genius drew on the fact that canola oil had 10% omega-3 fatty acids – which at that time was brand new to consumers. Canola oil began to be used interchangeably with olive oil, as the lighter alternative with the same healthy characteristics – something that could not have been further from the truth. Unprocessed canola oil which can not be found in our food supply does contain high levels of both monounsaturated fats and omega-3 fatty acids, but not the processed variety, the most common one. That is because a product with that much omega-3 fatty acids is not shelf stable. This marketing campaign was very successful and helped push this crop into one of the most widely planted in the world today. It is even the oil most commonly used in cholesterol lowering spreads in place of traditional margarines – a big mistake; and canola oil is the oil of choice in most restaurants.
The Dangers of Can-ugly Oil
There have been many warnings in the health food industry that canola oil is unhealthy and the average health food consumer understands the limitations of this oil. It is interesting to note that canola oil started its meteoric rise in popularity in the health food markets and now is shunned by the healthiest consumers. Several studies in animals have shown that canola oil can decrease the bio-availability of vitamin E, a critical component of cardiovascular health.
Also, canola oil consumption can lead to shortened life spans in other animals. In still another study, growth is retarded and hence the ban on the use of canola oil in infant formulas. If this was so safe, why can’t it be fed to human infants? Keep in mind that these studies were all done on animals and it is hard to make that leap into humans. The one thing that is known is that there have never been long term studies in humans as to the health benefits or to the dangers of canola oil – another uncontrolled experiment that only benefits one thing – the food processing industry. That is something to seriously consider when deciding which oil to reach for on the supermarket shelf.
I can’t help but wonder if canola oil in and of itself isn’t responsible for the dramatic rise in obesity and diabetes that we have experienced since it became fashionable. I guess it is something we will never know.