Back in the seventies it was rapidly becoming clear that research was pointing out that polyunsaturated vegetable oils, especially corn and soy, were not the healthy alternative to saturated fats. The health industry still promoted use of polyunsaturated instead of saturated fats based on research done in the fifties. (all of which has since been proven to be incorrect) A cheap and readily available substitute was needed and where there is a need, there will be a product to fill it. That product was the end result of nearly a decade of research into the foundations of genetic manipulation. Even though the Canadian Oil Council flatly denies that canola was developed through any sort of Genetic Modification, the truth is you can't always have what you want. And here, the truth is that the process isn't exactly like the GM technology of today, but the people that developed canola did in fact use very primitive gene splicing technology to develop the stuff. They even wrote a book about it, "The Rape of Canola". Anyway, that's a story for another time. Here, the reason for doing all this was because Rape was, and still is, the plant that produces more oil per acre than any other plant in the world. The original Rape, was not very useful for humans because it contained a high amount of Erucic Acid which is actually a long chain polyunsaturated fatty acid.
The result of the genetic manipulation was a new Rape plant that yielded a new product, LEAR, which stood for Low Erucic Acid Rapeseed. Kind of an ugly name. Marketing gurus thought that Canola was better, and so they made it so. To bad they just couldn't make all the ugly problems of the stuff go away as well. Erucic acid in fact is a very ugly problem and it does in fact destroy brain tissue by eating away the myelin sheath surrounding nerve cells and it has been known to cause heart lesions. These are in part some of the reasons that internet detractors of canola state that the stuff causes mad cow disease. They are only partly correct, once the canola processors figured out that they needed to process the cake leftover from oil production with lye to breakdown the erucic acid, the mad cow problem sort of dissipated. I guess you should know that the stuff leftover after they press out the oil is called cake, and that in the late seventies and eighties, the Canadians didn't want the stuff so they exported it all as cheap cattle feed. And guess who bought it all, well, England. Sort of a coincidence as to when and how the whole mad cow thing started.
In 1982 the Canadian Institute for Food Science and Technology published a paper that looked at the interaction of saturated fats with LEAR oil and soybean oil. They killed off a whole bunch of rats in their research to determine that when saturated fats in the form of cocoa butter were added to the diets, the rats in both groups had better growth and a significant lowering of heart lesions. their conclusion was, "These results support the hypothesis that myocardial lesions in male rats are related to the balance of dietary fatty acids and not to cardiotoxic contaminants in the oils." The Canadian Canola Council conclusion that LEAR, canola, is healthier because of the mix of fatty acids was thusly disproved by their own research. And the study was not in fact a long term feeding study using rats not prone to cardiovascular defects. The problem with the CIFST study showing that the erucic acid wasn't responsible is disputed by the NCBI study the same year about the stuff. "Rapeseed oil has a growth retarding effect in animals. Some investigators claim that the high content of erucic acid in rapeseed oil alone causes this effect, while others consider the low ratio saturated/monounsaturated fatty acids in rapeseed oil to be a contributory factor. Normally erucic acid is not found or occurs in traces in body fat, but when the diet contains rapeseed oil erucic acid is found in depot fat, organ fat and milk fat. Erucic acid is metabolized in vivo to oleic acid. The effects of rapeseed oil on reproduction and adrenals, testes, ovaries, liver, spleen, kidneys, blood, heart and skeletal muscles have been investigated. Fatty infiltration in the heart muscle cells has been observed in the species investigated. In long-term experiments in rats erucic acid produces fibrosis of the myocardium. Erucic acid lowers the respiratory capacity of the heart mitochondria. The reduction of respiratory capacity is roughly proportional to the content of erucic acid in the diet."
Canadian researchers looked at Canola oils again in 1997. They found that piglets fed milk replacement containing canola oil showed signs of vitamin E deficiency, even though the milk replacement contained adequate amounts of vitamin E. Piglets fed soybean oil-based milk replacement fortified with the same amount of vitamin E did not show an increased requirement for vitamin E. Vitamin E protects cell membranes against free radical damage and is vital to a healthy cardiovascular system. In a 1998 paper, the same research group reported that piglets fed canola oil suffered from a decrease in platelet count and an increase in platelet size. Bleeding time was longer in piglets fed both canola oil and rapeseed oil. These changes were mitigated by the addition of saturated fatty acids from either cocoa butter or coconut oil to the piglets' diet. These results were confirmed in another study a year later. Canola oil was found to suppress the normal developmental increase in platelet count.
Finally, studies carried out at the Health Research and Toxicology Research Divisions in Ottawa, Canada discovered that rats bred to have high blood pressure and proneness to stroke had shortened life-spans when fed canola oil as the sole source of fat. The results of a later study suggested that the culprit was the sterol compounds in the oil, which "make the cell membrane more rigid" and contribute to the shortened life-span of the animals.
These studies all point in the same direction, that canola oil is definitely not healthy for the cardiovascular system. Canola oil is associated with fibrotic lesions of the heart. It also causes vitamin E deficiency, undesirable changes in the blood platelets and shortened life-span in stroke-prone rats when it was the only oil in the animals' diet. Furthermore, it seems to retard growth, which is why the FDA does not allow the use of canola oil in infant formula. When saturated fats are added to the diet, the undesirable effects of canola oil are lessened.
Some basic info on fat
SATURATED FATTY ACIDS are chains of carbon atoms that have hydrogen filling every bond. In foods, they normally range in length from 4 to 22 carbons. Because of their straight configuration, saturated fatty acids pack together easily and tend to be solid at room temperature. Butter, tallows, suet, palm oil and coconut oil are classified as saturated fats because they contain a preponderance of saturated fatty acids. Saturated fats are stable and do not become rancid when subjected to heat, as in cooking.
MONOUNSATURATED FATTY ACIDS are chains of carbon atoms that have one double bond between two carbons and therefore lack two hydrogens. Normally they range from 16 to 22 carbons. They have a kink or bend at the position of the double bond so the molecules do not pack together as easily as saturated fatty acids. Monounsaturated oils tend to be liquid at room temperature but become solid when refrigerated. Olive oil, peanut oil, lard, rapeseed and canola oils are classified as monounsaturated oils. The most common monounsaturated fatty acids are palmitoleic (16 carbons), oleic (18 carbons) and erucic (22 carbons). Monounsaturated oils are relatively stable and can be used for cooking.
POLYUNSATURATED FATTY ACIDS have two or more double bonds. As there is a bend or kink at each double bond, these fatty acids do not pack together easily and tend to be liquid, even when cold. Polyunsaturated oils are very fragile. They tend to develop harmful free radicals when subjected to heat and oxygen, as in cooking or processing. Soybean oil, safflower oil, sunflower oil and flax oil are polyunsaturated oils. Omega-6 fatty acids have the first double bond at the 6th carbon from the end of the fatty acid chain. The most common omega-6 fatty acid is linoleic acid, which is called an essential fatty acid (EFA) because your body cannot make it. Omega-3 fatty acids have the first double bond at the 3rd carbon. The most common omega-3 fatty acid is the EFA alpha-linolenic acid. The consensus among lipid experts is that the American diet is too high in omega-6 fatty acids (present in high amounts in commercial vegetable oils) and lacking in omega-3 fatty acids (which are present in organ meats, wild fish, pastured egg yolks, organic vegetables and flax oil). Surfeit of omega-6 fatty acids and deficiency in omega-3 fatty acids has been shown to depress immune system function, contribute to weight gain and cause inflammation.
The three types of omega-3 fatty acids involved in human physiology are ALA(found in plant oils), EPA and DHA (both commonly found in marine oils)
Excess omega−6 fatty acids from vegetables oils interfere with the health benefits of omega−3 fats, in part because they compete for the same rate-limiting enzymes. A high proportion of omega−6 to omega−3 fat in the diet shifts the physiological state in the tissues toward the pathogenesis of many diseases: prothrombotic, proinflammatory and proconstrictive
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