We've all been told at some time or another that canola is one of the healthiest oils on the market. Canola, which is an Amalgam of the words "Canada" (whence it originated) and "oil," is actually derived from the rapeseed, a member of the mustard family which is generally unfit for human consumption and was once more commonly used as a potent pesticide and lubricant, among other things. Chemically, canola breaks down at 5% saturated fat, 57% oleic acid, 23% omega–6, and 10–15% omega–3.
The reason canola is particularly unsuited for consumption is because it contains a very–long–chain fatty acid called erucic acid, which under some circumstances is associated with fibrotic heart lesions.