Canola oil has been touted as a healthy oil to be used everyday. This plant based oil has a lot of supporters so it must be good for you, right? Unfortunately this is not the case. Looking more closely at how Canola oil is made you can see some of its drawbacks. The process is hardly natural. Canola oil is made from Rape seed. Rape seed contains eurcic acid which is toxic to humans. It has been genetically bred to lower its eurcic acid content. This lower eurcic acid rape seed is pressed and mixed with chemical solvents and heated to high temperatures to recover the oil in it. (Remember high heat can make oil rancid.) The oil is then “washed with sodium hydroxide” to remove impurities. Next it is bleached to make the color lighter. It is then deodorized to remove its strong and unpleasant smell. Finally it is bottled and ready for use. In other words Canola oil is a highly refined product.
Research on vegetable oils, including Canola oil has shown that it causes systemic inflammation; this is due to the abundance of Omega 6 fatty acids . Humans evolved eating a diet that was balanced with a 1 to 1 ratio of omega 6 to omega 3 fats. Omega 3 fatty acids are found in cold water fish and nuts. With changes in food production, industrial farming and the urging of doctors and other health officials to eat canola and other vegetable oils that ratio has changed to 20 omega 6 fatty acids to 1 omega 3 fats . Interesting that decreasing consumption of Omega 6 can also improve the anti-inflammatory properties of Omega 3s. This is important information for those spending their money on supplementing omega 3s using fish oil, borage oil, flax seed oil etc.  In addition contributing to inflammation Canola oil has been shown to deplete vitamin E in animals 
Canola is in the top 3 of genetically modified foods sold in the US. Natural news calls it “among the most chemically altered foods in our diets.” Canola oil or its unhealthy counterpart soybean oil is in most processed foods so always check the label!
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J. D. Heyes.(June 1, 2012). Infographic unveiled: top ten GMO foods to avoid eating. Retrieved July 23, 2014. Source