During World War II Canada planted vast fields of mustard plants to provide mustared oil for the lubrication of steam machinery (the supply from China had been cut off). After the war they needed to find a new market.

Seeing the success of partially hydrogenated cotton seed oil (formerly used to make soap) and soybean oil (formerly used for oil based paint), sold as "health food" when the original market failed, they chose to sell this oil as "health food".

Supposedly erucic acid in mustard oil caused heart lesions, so the FDA wouldn't allow Canada to sell mustard seed oil as a cooking oil until they lowered the erucic acid content.

Canola Oil is actually LEAR Oil (Low Erucic Acid Rapeseed) but Canada felt they couldn't sell it under that name.

It now seems the erucic acid isn't the actual cause of the heart lesions, because they still appear in rats fed a lot of Canola oil.

The kicker is that they found a sufficient amount of saturated fats in the diet protected the rodent hearts from the ravages of Canola oil.

This is supported by demographics. Straight high erucic acid mustard oil is much used for cooking in parts of China. The heart lesion problem only appears during times of famine when no pig fat is available in the diet.

The late Mary Enig, one of the foremost experts in dietary fats. co-authored a book titled "The Great Con-ola" describing the history and health problems involved with Canola oil and the tremendously successful marketing campaign that sold a questionable product as "health food".

Today, you have to search hard to find a recipe in any newspaper or magazine, or recently published cookbook, that does not specifically call for Canola oil.