Canola oil is mostly GMO at this point in time. And regardless, canola oil creates a great deal of inflammation. It’s especially damaging to your digestive system, potentially scarring the linings of both your small and large intestines, and is a major cause of irritable bowel syndrome. Canola oil can feed viruses, bacteria, fungus, and mold. Beyond that, canola oil has an effect similar to battery acid on the inside of your arteries, creating significant vascular damage.