GMOs
Another concern about canola oil is that it is a genetically modified food product (or a GMO, as it is more commonly known). GMO products may be higher in certain pesticides, and I think at this point it is worth giving them a second thought and working around them whenever possible.
Thankfully, about 20% of the canola oil crops that are made are GMO-free. This is information that can be easily found on labeling, especially as more and more people seek out products which are not associated with GMOs. All you have to do is check the label, and you will be able to tell whether or not it is GMO-free.
Trans Fat Content
Some have recommended avoiding canola oil because of the amount of trans fats. This is a spot-on concern, because the more you can avoid and minimize the trans fats the better you will ultimately feel. Trans fats, especially those which are hydrolyzed, clearly associated with more risk of heart disease4 and more inflammation in the body.
Trans fats may also be found in many other oils which are extracted using high levels of heat. Refined, heat and chemically-extracted canola oil, in 2015, was found to have 0.46% trans fats5. For context, butter contains 3.5% trans fats (on average) – with clarified butter roughly containing 4% trans fats6.