All About Oils

All About Oils

By: Holly Barrett


Cooking with oils – do you have to choose between cooking for taste or cooking for health? There is no shortage of opinions when it comes to deciding which oils are best.


When it comes to calories, all cooking oils are equal. Regardless of what oil you use, nutritionally, oil is classified as a fat. Fats are far more calorie dense than carbohydrates and protein (fats = 9 calories/gram; carbs and proteins = 4 calories/gram).


When it comes to health effects, all cooking oils are not equal. For cooking oils, the best kinds are those with low rates of oxidation. Oxidation occurs when oils are exposed to heat, air, and light (depending on the oil). Different oils have different levels of stability. The more stable the oil, the less easily it begins to turn rancid through oxidation. Oxidation promotes free radicals, chemicals that are highly reactive and have the potential to damage cells, including damage that may lead to cancer.


Oil Extraction Methods


Many cooking oils go through an excessive amount of processing with chemical solvents, steamers, neutralizers, de-waxers, bleach and deodorizers before they end up in the bottle.


Some oils are extracted using a solvent called hexane. Hexane is an inexpensive byproduct from gasoline production, a serious occupational hazard, a toxic air pollutant, and a neurotoxin. It’s been shown that some hexane residue can remain in the oil, and the FDA doesn’t require food manufacturers to test for residues. Residue tests done by the Cornucopia Institute in 2009 found hexane residues in soybean oil. So, we very well could be eating this chemical every time we cook with hexane-extracted oils. Almost all toxicology research focuses on the industrial use and inhalation of hexane, so no one knows exactly how dangerous eating it is – but it surely isn’t healthy.


Expeller pressed oil means that the oil was mechanically extracted with a screw press. This traditional way of making oil is much healthier than using solvents, such as hexane. Expeller pressing is not as commonly used because it is less effective (meaning, manufacturers see a lower yield) and it’s more expensive. The expeller pressing process can cause a lot of heat that can make the oil go rancid (oxidation), so, to preserve the quality of the oil, some companies practice a cold press process and keep their oils at temperatures between 80°F to 120°F. This processes is more labor intensive but results in a higher quality, healthier oil.


Safest for Cooking

Great for frying, baking, broiling, grilling, and roasting

  • Coconut Oil (organic, virgin)
  • Lard
  • Ghee
  • Beef and Lamb Tallow
  • Chicken, Duck, and Goose Fat
  • Red Palm Oil, Palm kernel oil (organic, sustainably harvested virgin)


*Animal fats should ideally be sourced from organically raised, grass-fed pastured animals
*Tropical vegetable fats in this category should ideally be organic and unrefined in nature.


 Safe for Cooking

Quick stir-frying, light sautéing, and slow/low simmering are appropriate forms of heat for these oils. Again, notice the commonality of these fats. All except sesame oil contain most monounsaturated fatty acids.

  • Olive Oil (unfiltered, domestic)
  • Peanut Oil
  • Avocado Oil
  • Macadamia Nut Oil
  • Sesame Oil

These oils should ALWAYS be extracted via expeller-pressing! Read the label first!




Unsafe for any kind of Heat Exposure! DO NOT use for Cooking! 

  • Flax Oil
  • Hemp Oil
  • Pine Nut Oil
  • Pumpkin Seed Oil
  • Safflower Oil
  • Sunflower Oil
  • Grapeseed Oil



*These oils are primarily composed of polyunsaturated fatty acids (PUFAs), and should not be heated. If you do wish to consume these oils, do so in small doses. You can find these oils in dark, glass or thick plastic containers in a refrigerated section of most health food stores. PUFA dominant oils should never be refined or processed, and unfortunately, finding truly unprocessed versions of these oils can be a difficult task. Corn and soybean oils are best avoided due to their genetically modified status and heavy pesticide levels.


Use omega-3 rich oils like flax oil sparingly in homemade condiments such as salad dressings, mayonnaise, freshly prepared smoothies, or lightly drizzled over soups, dips, and hors d’oeuvres.

There are many conflicting opinions about the safety of cooking with grapeseed oil. Like sesame oil, it has a higher smoke point due to its antioxidant content. Regardless, grapeseed oil is very high in PUFA’s and should not be used for cooking.


Unsafe to Consume Under any Circumstances

  • Canola Oil/Rapeseed Oil
  • Corn Oil
  • Cottonseed Oil
  • Soybean/Vegetable Oil/Vegetable Shortening
  • Partially Hydrogenated Fats/Oils (all)


More About Unsafe Oils…

The oils listed above are the oils commonly found in packaged foods, fast foods, convenience foods and fried foods. They are commonly used because they are inexpensive and have long shelf lives. They have zero health benefit and actually cause bodily harm.


Canola Oil

To better understand this oil, it helps to know where it comes from. Canola oil is extracted from rapeseed plants, that have been bred to have lower levels of toxic erucic acid. Before it was bred this way, it was called Rapeseed Oil and used for industrial purposes because the erucic acid in it caused heart damage in animal studies. It got the fancy new name “canola”, but it still contains trace amounts of erucic acid (up to 2%, which they consider “safe”). In 1995 they also began genetically engineering (GMO) rapeseed to be resistant to herbicides, and now almost all canola crops in North America are GMO. Canola oil consumption has been linked to vitamin E deficiency and a shortened life span in animal studies. Research has also found some trans fats in canola oil, which were created during the heavy processing that it goes through. These trans fats are not labeled. This is ironic because trans fats are the opposite of heart healthy!


According to the Weston A. Price Foundation:


“Like all modern vegetable oils, canola oil goes through the process of caustic refining, bleaching and degumming–all of which involve high temperatures or chemicals of questionable safety. And because canola oil is high in omega-3 fatty acids, which easily become rancid and foul-smelling when subjected to oxygen and high temperatures, it must be deodorized. The standard deodorization process removes a large portion of the omega-3 fatty acids by turning them into trans fatty acids…research at the University of Florida at Gainesville, found trans levels as high as 4.6 percent in commercial liquid oil… they are not listed on the label”.


Mazola and Crisco brands both admit to using GMOs and hexane extraction in their processing. Wesson oil has confirmed that GMO canola is used.


Note: Spectrum Organics brand does not use hexane to process their canola oil, and as with any organic oil, it’s non-GMO. However, I don’t consider canola a healthy oil and would choose another type of oil instead.


Corn Oil

Corn oil is highly refined, hexane-extracted from GMO corn, and loaded with omega-6 polyunsaturated fatty acids that are unstable when exposed to heat. This instability causes oxidation. As mentioned earlier in this post, oxidation is a process that generates free radicals. Free radicals are renegade molecules in the body that damage cells, triggering a host of diseases from liver damage to cancer.


Cottonseed Oil

Cottonseed oil is a byproduct of the cotton crop that’s inundated with pesticides and chemicals because it’s regulated as a textile crop – not food! Cottonseed oil does not belong in our food supply and should be strictly avoided. Thankfully, most cooking oils in the grocery store no longer contain cottonseed oil, and this ingredient is mostly relegated to the processed food aisle. Cottonseed is widely being replaced in cooking oils with another oil that should be avoided: soybean oil.


Soybean Oil

Most products that just say “Vegetable Oil” are made from soybeans. It’s so common in processed foods that up to 20% of calories in the typical American diet is thought to come from soybean oil. Soybean oil is high in omega-6 fatty acids, and our bodies need this type of fatty acid, but today people are getting too much of it through processed foods – up to 20 times more than required, according to some estimates.


The overabundance of omega-6 fatty acids increases the risk of inflammation, cardiovascular disease, cancer, and autoimmune diseases. Soybean oil is also typically made from GMOs, as 94% of U.S. soybean crops are genetically modified. A recent survey showed that most Americans use “Wesson Vegetable Oil”, which is now made from soybeans (previously cottonseed).


Wesson brand is owned by Conagra Foods, which has donated over $2.6 million dollars to fight GMO labeling laws in the U.S., so, every time you buy their products, you help fund these anti-labeling campaigns. Smart Balance cooking oil is a soybean oil blended with canola and olive oils.


When Food Babe contacted Smart Balance for more information regarding their products and labeling, they were told, “we plan to transition our full product line to non-GMO including our Smart Balance Oil. At this time our oil is not expeller pressed and does contain GMOs.” and “We do not know if hexane specifically is used but we do know it is a chemical process”.


Don’t Be Afraid of REAL Butter!

If you are not following a vegan or vegetarian diet, don’t forget about the queen of cooking fats –  real butter.


Butter is a true nutritional gem and our ancestors prized butter for its life-giving nutrients! Raw, unprocessed butterfat from grass-fed cows has a comprehensive fatty acid profile that protects its consumer from developing imbalances such as hardening of the arteries, calcification of organs, glands and joints (arthritis), and cataracts.


Quality raw butter contains:

  • Omega-3 and Omega-6 fatty acids in small amounts in a healthful ratio
  • CLA (Conjugated Linoleic) fatty acids to support weight management, muscle growth, and may protect against cancer
  • Fat soluble vitamins A, D, E, and K to help us absorb and properly assimilate naturally occurring trace minerals also found in raw butter (zinc, selenium, iodine, chromium, manganese, etc,)
  • Butyric fatty acids that may help protect against fungal infections and tumor growth
  • Arachidonic fatty acids for proper inflammatory and anti-inflammatory responses to heal effectively

Also, butterfat enhances brain function and increases cell membrane integrity. With all these health benefits, raw organic butter can be a dietary fat consumed each day.




Choose your fats wisely to ensure they have been minimally and safely processed, or better yet, not processed at all. Remember, healthy fats are an important macronutrient component of our diet!

Consume a wide variety of fats from whole oils to whole foods containing healthy fats and carefully monitor and limit your consumption of PUFAs. If you want to learn more about fats and the important role they play in balanced health, read these two eye-opening articles titled, The Skinny on Fat and The Oiling of America. These articles are a must-read for anyone wishing to regain their health and vitality.






Much of the information stated in this article here is from the work of Dr. Mary Enig, PhD and Sally Fallon, coauthors of the above linked articles, Vani Hari at, and the Nourishing Traditions book by Sally Fallon.


Additional Vitamin E Required in Milk Replacer Diets that Contain Canola Oil

Birke Reports – Don’t Let Cooking Oils Fool You

Genetically Modified Crop on the Loose and Evolving in U.S. Midwest


The importance of the ratio of omega-6/omega-3 essential fatty acids.


Toxicological Profile for n-Hexane

U.S. population: Which brands of salad or cooking oil have you used most often in the last 90 days?

Vegetable oils high in phytosterols make erythrocytes less deformable and shorten the life span of stroke-prone spontaneously hypertensive rats.






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