Knowing which oils are safe to eat and cook with can be difficult, as there is so much conflicting information out there.
But before we can sort through it all, we need a brief science lesson. (I promise, this will be painless!)
We first need to understand a little about fats in general.
Fats can be divided into 3 types:
- Saturated fats (coconut oil, animal fats, dairy fats)
- And 2 types of Unsaturated fats:
- Mono-unsaturated fats (olive oil, avocado, nuts and seeds)
- Poly-unsaturated fatty acids
The poly-unsaturated fats (PUFAs) can be further broken down into two types of essential fatty acids. Essential fatty acids are fats which your body cannot produce on its own, so they must therefore be obtained from your diet. The two main types of essential fatty acids are:
- Omega-6 (linoleic acid): obtained mainly from vegetable oils, and
- Omega-3 (alpha-linolenic acid): obtained from fatty fish, walnuts, chia seeds, flaxseeds, hemp seeds, and egg yolks.
Ideally, we want the ratio of omega-3 to omega-6 fats which we consume to be 1:1. But unfortunately, the ratio in a typical modern diet is between 1:20 and 1:50! So most of us are consuming far too many Omega-6 fatty acids, and far too little Omega-3s.
What’s the problem with vegetable oils?
-
Vegetable oils are high in omega 6 fatty acids.
While our bodies do need some omega 6 fats, the modern diet is much too high in omega 6 fats. The ratio of omega 6 to omega-3 in corn oil, for example, is 49 to 1!
Poly-unsaturated fatty acids (PUFAs) contain compounds that are very chemically unstable. They quickly become rancid and when consumed cause inflammation and many health problems. Excessive amounts of omega-6 PUFAs and a very high omega-6/omega-3 ratio has been found to promote the pathogenesis of many diseases, including heart disease, cancer, and inflammatory and autoimmune diseases. This study showed that omega-6 PUFAs may promote breast cancer development. A similar effect was shown on prostate cancer in this study.
-
The vast majority (80-90%) of vegetable oils are made from genetically modified crops.
This study showed that a diet which includes genetically modified organisms (GMOs) can lead to liver and kidney problems. Cancer, birth defects, and infertility are other suspected side effects.
-
These crops are often heavily treated with pesticides.
-
Vegetable oils are highly processed.
Unlike butter or coconut oil, vegetable oils can’t be produced naturally. They must be chemically extracted, degummed, deodorized, bleached, hydrogenated, and dewaxed. Doesn’t that sound appetizing? A picture speaks a thousand words…
-
Many vegetable oils are partially hydrogenated and contain toxic trans fats.
- Trans-fats are formed when hydrogen is added to vegetable oils to make the fat less likely to spoil. This process, called hydrogenation, results in an unnatural and poisonous substance.
- In June of 2015, the FDA (U.S. Food and Drug Administration) determined, based on extensive research, that trans fats are “not Generally Recognized as Safe.” In fact, within 3 years of the FDA announcement, trans-fats will be banned from the US food supply.
- Harvard School of Public Health notes that trans-fats promote immune system over-activity and inflammation and are linked to heart disease, stroke and diabetes, among other chronic diseases.
Oils to avoid:
Corn oil | Vegetable oil | Crisco |
Canola oil | Peanut oil | Sunflower oil |
Safflower oil | Soybean oil | Margarine |
All of these oils are too high in poly-unsaturated fats.
So what should I use instead?
Our ancestors (who saw very little cancer, diabetes, and heart disease) obtained their fats through natural sources such as butter, tallow, coconut oil, & olive oil.
Every single cell in your body primarily uses saturated & mono-unsaturated fats for its functioning (97%). Doesn’t it therefore make sense that we need to eat a higher amount of those, and a lesser amount of poly-unsaturated fatty acids?
The fats and oils I recommend are:
- Coconut oil: Since the fat in human cells is mostly saturated fat, it is important to get enough of it from healthy sources. Coconut oil is very stable and does not oxidize easily at high temperatures or go rancid easily, making it great for cooking and baking.
- Butter or ghee: grass-fed butter is a healthy fat and an excellent source of fat soluble vitamins and other nutrients.
- Olive oil: for low temperature usage (heating olive oil to high temperatures can cause the oil to oxidize and become hydrogenated). I usually use olive oil in things like salad dressings and hummus.
- Other sources of healthy fats: grassfed beef and free range chicken and eggs, fish, avocado, nuts (in moderation).
What about sunflower oil?
Sunflower seeds are healthy. So the oil must be healthy too, right?
Unfortunately this is not the case. There are different types of sunflower oils, but most are high in Omega 6 fatty acids, which as we’ve discussed, cause inflammation in the body when eaten in excess.
Sunflower oil does contain vitamin E, but most of the sunflower oil found in supermarkets is highly refined and therefore stripped of vitamin E.
An exception to this would be a cold pressed, high oleic, unrefined, organic sunflower oil, which is higher in mono-unsaturated fatty acids and a good source of vitamin E.
What about Canola oil?
Canola oil contains a balanced ratio of Omega-6 and Omega-3 fats. So is it healthy?
Unfortunately, no.
It’s true that our bodies do need a small amount of poly-unsaturated fats, and that the ratio of omega-6 to omega-3 fats in canola oil is balanced. But, using canola oil as your primary cooking oil would give you too much poly-unsaturated fats in your diet. As I said above, the fat content of the human body is about 97% saturated and mono-unsaturated fat, with only 3% poly-unsaturated fats. So we only need a small amount of these fats.
Other reasons to avoid canola oil:
- Over 90 percent of canola oil is genetically modified.
- Canola oil is a refined oil that’s often partially hydrogenated, making it unhealthy. (Read more about hydrogenated oils here)
Faiza says
salaam Laura Dear
Love reading your post
Miss u
Dr. Laura says
Walaikum assalaam wa rahmatullah,
I miss you too Faiza!
Thanks for the sweet comment
Umm Zakwan says
Very well explained!
Dr. Laura says
Thanks Umm Zakwan!
Tracy L. Stevens says
Very good information, thanks Dr. Laura !
Dr. Laura says
Thanks for your comment Tracy!