Canola oil is often touted as a heart-healthy alternative to "bad" animal-based saturated fats. However, canola oil is a highly-processed industrial product that contributes to inflammation in the body, making it the OPPOSITE of heart-healthy.
How is Canola Oil made?
The process for making Canola shown in delicious detail in the video below. After a first press to remove oil, the seeds are pressed a second time and washed with "solvent" (read: hexane, a toxic substance that is still present in the final product in very small amounts). The resulting sludge then goes through de-gumming, bleaching, and deodorizing before it is suitable for human consumption.
Canola Oil in the Body.
Canola is generally considered "heart healthy" due to its low saturated fat content (though recent research and centuries of human history would argue that saturated fat is exactly what you want). The opposite of saturated is unsaturated, which in chemical terms means reactive. Canola oil is a polyunsaturated fat, which means it is capable of reacting at multiple places on the molecule. (To contrast, olive oil is a monounsaturated fat, meaning it has one spot on each molecule where it can react. Olive oil IS a healthy fat that can be obtained without an industrial process. However, it should be stored in a cool, dark place and only used for low-temperature cooking to avoid oxidation.)
So, what happens to oxidized unsaturated fats in the body? (Oxidized is the key word here. There are health benefits from naturally-occuring unsaturated fats. Unsaturated fats are also an important component of the cells walls of fish. ) These oxidized fats are not recognized by the body as food. The human body evolved (or was designed, your choice) to process naturally occurring substances.
Any part of the molecule that was not already oxidized undergoes random oxidation once inside the body. These molecules ultimately break down into free radicals. These free radicals promote inflammation in the body and are the likely cause of cancer, premature aging, and atherosclerosis (heart disease).  Recent research is also beginning to show that inflammation may be the root of all disease.
Another reason for its promotion as "heart healthy" is the content of omega-3 fatty acids. Omega-3 fatty acids are known to be a healthy addition to the diet, however, canola oil also contains a significant amount of omega-6 fatty acids, which will prevent the consumer from achieving a healthy omega-6/omega-3 balance.
So, what types of fat should I use?
The best choices will always be fats that are found in nature or that can be obtained with minimal processing: coconut oil, olive oil, fat from pastured/grass-fed animals, BUTTER. If it is found in nature and it tastes good, then it is probably good for you!
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