Dangers of Canola Oil
January 16, 2000
By Dr. Mercola
Although canola oil is not a favorite oil with me for a number of reasons (none of which were listed in the article), the statement suggesting that because it is used as an industrial oil it is therefore not edible is not valid. Flax oil is also used as an industrial oil for paint and linoleum, etc. But when it is prepared as a food it is edible. Most oils have been used at one time or another as industrial products. In my opinion, one of the most edible oils is coconut oil, which is used for many industrial products, especially for soaps and cosmetics.
Olive oil apparently has been used to make soap for as long as it has been used as a food oil. Perhaps the most blatant error and comparison made by Mr. Lynn, though, is that regarding canola oil and mustard gas, which chemically has absolutely no relationship to mustard oil or any other mustard plant. Mustard gas is 2,2'-dichlorodiethyl sulfide and its preparation using ethylene and sulfur chloride is given in the Merck Index. It received its name because of the yellowish color of the gas and the sulfur odor.
Regular rapeseed and canola oils are extracted from the seeds of several of the brassica plants - the same family of plants from which we get vegetables such as Brussels sprouts, broccoli, cabbage, kale, mustard greens, and several other vegetables.
Of course, there is not much fat in these vegetables; but what fat there is in some of them, e.g., mustard greens, is as much as 29 percent erucic acid. Also, since glycosides (typical are stevioside and other flavonoids) are basically water soluble, I would not expect to find much of them in any oil. Those glucosinolates found in rapeseed meal after the oil has removed from the seeds are the same goiterogens that are found in the brassica vegetables. One problem with canola oil is that it has to be partially hydrogenated or refined before it is used commercially and consequently is a source of trans fatty acids; sometimes at very high levels.
Another problem is that it is too unsaturated to be used exclusively in the diet; some of the undesirable effects caused by feeding canola can be rectified if the diet is made higher in saturated fatty acids.
Mary G. Enig, Ph.D., Director Nutritional Sciences Division Enig Associates, Inc.