Canola oil is much healthier than olive oil. It contains lower levels of erucic acid than rapeseed oil.
From Wikipedia: “Canola is a cultivar of rapeseed bred to be low in erucic acid. As a term canola may refer to both an edible oil (also known as canola oil) produced from the seed of any of several varieties of the Brassicaceae family of plants, and to those plants, namely a cultivar of Brassica napus L., Brassica rapa subsp. oleifera, syn. B. campestris L. or Brassica juncea. To be called canola, the oil must contain less than 2% erucic acid and the meal must contain less than 30 micromoles of aliphatic glucosinolates per gram.
Consumption of the oil is common and is claimed not only to be completely safe for human and animal consumption, but also to be among the healthiest of plant-derived oils, having a relatively low amount of saturated fat and a high content of polyunsaturated fats. It is also used as a source of biodiesel.”
“Canola oil is made at a processing facility by slightly heating and then crushing the seed. Almost all commercial canola oil is then extracted using hexane which is recovered at the end of processing. Finally, the canola oil is refined using water precipitation and organic acid to remove gums and free fatty acids, filtering to remove color, and deodorizing using steam distillation. Cold-pressed and expeller-pressed canola oil are also produced on a more limited basis. About 44% of a seed is oil, with the remainder as a canola meal used for animal feed. About 23 kg (51 lb) of canola seed makes 10 L (2.64 US gal) of canola oil. Canola oil is a key ingredient in many foods. Its reputation as a healthy oil has created high demand in markets around the world, and overall it is the third-most widely consumed vegetable oil.
The oil has many non-food uses and, like soybean oil, is often used interchangeably with non-renewable petroleum-based oils in products, including industrial lubricants, biodiesel, candles, lipsticks, and newspaper inks, depending on the price on the spot market.
The average density of canola oil is 0.92 g/ml.”
“A review in 2013 of health effects of canola oil came to overall favorable results, including a substantial reduction in total cholesterol and low-density lipoprotein (LDL) cholesterol, and an increase in tocopherol levels and improved "insulinsensitivity", compared with other sources of dietary fat.
Regarding individual components, canola oil is low in saturated fat and contains both omega-6 and omega-3 fatty acids in a ratio of 2:1. It is high in monounsaturated fats, which may decrease the risk of heart disease.
Canola oil has been given a qualified health claim from the United States Food and Drug Administration for lowering the risk of coronary heart disease resulting from its significant content of cholesterol-lowering unsaturated fats; the allowed claim for food labels states:
"Limited and not conclusive scientific evidence suggests that eating about 1 ½ tablespoons (19 grams) of canola oil daily may reduce the risk of coronary heart disease due to the unsaturated fat content in canola oil. To achieve this possible benefit, canola oil is to replace a similar amount of saturated fat and not increase the total number of calories you eat in a day.”
Canola oil poses no unusual health risks, and its consumption in food-grade forms is generally recognized as safe by the United States Food and Drug Administration.”
“Although wild rapeseed oil contains significant amounts of erucic acid, the cultivars used to produce commercial, food-grade canola oil were bred to contain less than 2% erucic acid, an amount deemed not significant as a health risk. To date, no health effects have been associated with dietary consumption of erucic acid by humans; but tests of erucic acid metabolism in other species imply that higher levels may be detrimental. Canola oil produced using genetically modified plants has also not been shown to explicitly produce adverse effects.”
“Europe has invested heavily in infrastructure to use canola oil for biodiesel, spurred by EU biodiesel policy initiatives.”