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Canola Oil Safety

Many people believe there is an issue regarding the safety of canola oil. And yet, if you ask these people why, all they can do is refer to widespread rumours that have been circulating in anti-canola oil emails these last twenty years.

To many, it’s a mystery. They don’t know if you hunt it, fish it, or grow it. But they know that somehow “canola” can be used to produce cooking oil. And, as is often the case with foods of a somewhat baffling origin, there are questions that arise in people’s minds, particularly when it comes to health. So let me cut to the chase. Canola is a plant that produces seeds. These seeds can then be pressed to yield oil. It is one of the best, safest, and most economical oils that can be used in food preparation.

Now, that is not exactly what you may have heard or read before, is it? You may have heard that the name “canola” was invented to distract consumers from the fact that the oil actually derives from the toxic rapeseed plant and is responsible for causing glaucoma, respiratory problems, neurological diseases, and malfunctions of the immune system. And to top it off, you may even have heard that canola oil is the source of the notorious chemical warfare agent, mustard gas. The source of all this claptrap is an e-mail that has been widely circulating since about 2001 and seems to gather more nonsense with each go-around. The latest gem recounts the saga of a woman whose arm was “slightly banged and split open like it was rotten.” She then called her mother to ask what could have caused it. (Strange, one would think that if your arm splits open your first reaction would be to go to the hospital.) In any case, the astute mother remarked, “I’ll bet anything you are using canola oil!” And sure enough, we are told, there was a big jug of the oil in the pantry. Is it possible that some people actually believe such hogwash? Judging by the questions I’ve gotten on this issue, the unfortunate answer is “yes.”

Attempts to trace the origin of the stunning information in the anti-canola e-mail always end at the same place. The word was revealed by John Thomas in his 1994 book “Young Again”, in which Thomas claims to have reversed his “bio-electric age” (whatever that may be) by eliminating the likes of canola and soy oil, using liver cleansers (which he sells), drinking specially filtered water (which he also sells), and taking dietary supplements that are specially tuned to the “frequencies” of his body. Readers can get in on this too by sending Thomas a picture of themselves which can be analyzed by a special machine (which he has) to determine their personal frequencies, which can then be used to customize appropriately tuned dietary supplements (which surprise, he also sells). And what qualifications does this remarkable man who was encouraged to write "Young Again" because he supposedly "does NOT age" actually have? As far as I have been able to find, none! Aside from a nondescript picture on the book’s back cover, I can’t find hide nor hair of John Thomas. It is amazing, though, how a vacuous nobody has been able to make so many people twitch about the safety of canola oil.

About the only thing Thomas got right in his silly diatribe is that “canola” is indeed a name that was coined for a special variety of rapeseed. It comes from a clever combination of the words “Canada,” “oil” and “low acid.” Rapeseed oil has long been used as a lubricating oil, but its somewhat bitter taste, due to compounds called glucosinolates, impaired its use in food. There was also an issue about another component, erucic acid, which in some animal studies, when incorporated into the diet in grotesque amounts, caused fatty deposits in several organs. Last century, Canadian researchers, using traditional plant breeding methods, managed to develop rapeseed with a low glucosinolate level and minimal erucic acid content. The oil pressed from the seeds of these plants became “canola oil.”

Like all oils, canola is composed of three fatty acids linked to a backbone of a glycerol molecule. Both the cooking performance and health properties of fats and oils are determined by the types of fatty acids they contain. Saturated fats, containing no carbon-carbon double bonds in their structure are implicated in heart disease but can be repeatedly heated when it comes to frying. Monounsaturated fats, with their one double bond, and polyunsaturated fats, with their many bonds, are more heart-healthy, but less stable to heat. Some polyunsaturated fats, such as alpha-linolenic acid (an omega-3 fatty acid), have been specifically linked with protection against heart disease. It turns out that of all the commonly used oils, canola has the lowest content of saturated fats, and next to flaxseed oil, the second-highest content of alpha-linolenic acid. Actually, one of the best ways to judge the health properties of a fat, aside from being low in the saturated variety, is the ratio of omega-6 to omega-3 fatty acids. (The numbers refer to particular positions of the double bonds in the molecular structure.) Canola oil has the ideal ratio of 2:1.

Because canola is so high in unsaturated fats, it does not stand up well to prolonged heating as is required in restaurant frying and does not have the keeping qualities desired by food production industries. Hydrogenating the oil makes it more suitable, but also introduces the notorious “trans-fats.” Indeed, it is a good idea to minimize the intake of hydrogenated fats, whether these come from soy, corn, canola, or any other oil. As far as home use goes, though, non-hydrogenated canola oil is a great all-purpose oil. Incidentally, there is no truth to the rumour that heating unsaturated oils produce trans fats. Heating foods to a high temperature, however, does produce some nasty compounds that are widely regarded as carcinogens. That’s why any sort of frying should be limited. I use canola oil to fry my Wienerschnitzel, but I use the oil only once, and of course, do not indulge in this delicacy very often. But when I do, I have no concern about being deprived of my life force “chi,” being poisoned by cyanide, or having my brain damaged à la mad cow disease, all of which, at least according to the "expert" John Thomas, are consequences of canola consumption. 


@JoeSchwarcz

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