Is Canola Oil Really Toxic?

Canola oil is second in terms of monounsaturated fat in oils, bested only by olive oil. It is versatile and healthy. Unfortunately, myths and rumors have tarnished its image in recent years. Although some people may elect to choose unrefined, organic brands, it is my professional opinion that there is no reason to avoid this oil entirely.

Canola Oil and Alzheimer’s Disease

The newest nail in canola oil’s undeserved coffin is reporting that it increases the risk of Alzheimer’s disease. The media frequently refers to a study that utilized six-month-old mice genetically engineered to develop plaques in their brains, similar to those with Alzheimer’s disease. For six months, the mice received either a control diet or a diet that contained the equivalent of about a teaspoon of oil per 200 pounds of food. That’s right – a measly teaspoon per 200 pounds of food! It’s unlikely that this minuscule amount of oil would have much of an effect on the risk profile of these doomed animals.

The plaques (amyloid) that form in the brain of someone with Alzheimer’s disease might be a marker and not a cause of the disease. Destroying amyloid doesn’t seem to reverse the symptoms of Alzheimer’s disease. The study didn’t detail how much food the mice ate or what the control diet consisted of, and the results were not scientifically significant. There was no difference in the mice’s performance in a water maze, either.

Read more about the erroneous research study on the Center for Science in the Public Interest website.

Canola Oil and Heart Disease

The idea that canola oil causes cardiovascular disease also doesn’t hold water; crossbreeding rapeseed has eliminated almost all of the erucic acid tied to heart disease from the canola plant. The FDA also regulates how much erucic acid is allowed; the limit is currently two percent.

In a study often reiterated by misled individuals, researchers fed canola oil as the only fat in the diet to a unique strain of rat predisposed to developing high blood pressure and suffering strokes. The animals developed stiffened cell membranes and kidney damage before succumbing to premature death more quickly than usual. However, this particular strain of rats absorbs toxic amounts of phytosterols from the oil, accounting for its toxicity. 

Genetic Modification and Processing

The fact that most canola oil is genetically modified today creeps a lot of people out. If you’re concerned about GMOs, purchase organic brands. However, I should emphasize that canola oil is not processed differently than other seed oils, such as soy, corn, or sunflower oils.

Many oils, including canola, are extracted using hexane, which is a flammable chemical. However, the canola oil that you have in your kitchen is essentially hexane-free. No evidence proves that this method of processing produces an oil that is unfit for consumption.

When canola oil is heated to high temperatures for a very long time, linoleic acid (a healthy fatty acid also found in corn, safflower, and soybean oils) is broken down into a compound known as HNE. HNE has been linked to heart and liver disease, as well as neurological problems. However, canola oil has a high smoke point, so it is OK to use for a typical length of time when frying or sauteing foods.