High Oleic Oil and Other Important Considerations When Choosing a Vegetable Oil

High Oleic Oil and Other Important Considerations When Choosing a Vegetable Oil

What is the Best Cooking Oil?

This is a question that I am asked all the time. If you had asked me this question a few years ago my answer would have been different. But, now with more research on high oleic oils, I am excited to share with you my current recommendations for what type of cooking oil you should use.

As well as covering the evidence for high oleic oils, I also want to discuss with you other oil attributes, and my opinion on whether they matter or not. I will share some label reading examples too, so you know what to look for when shopping.

What are High Oleic Oils?

High oleic oils are vegetable oils with a high amount (usually 70% or higher) of oleic fatty acid, otherwise known as omega-9 fatty acid.

Why are they called High Oleic Oils?

Fats and oils are made of fatty acids, and these fatty acids are in different proportions in various oils. When an oil has a high amount of oleic acid of about 70%  or more it is called “high oleic”. 

Why Should I Use a High Oleic Oil?

Olive oil is probably the most well-known high oleic oil, with about 68% oleic and (18). It gained attention since the  7-Countries study was published in the 70’s, which showed that people in the Mediterranean who had a diet high in olive oil had the lowest risk of heart disease. Since then, research has accumulated on the health protective properties of olive oil and oleic acid. 

Are High Oleic Oils the Best Cooking Oils?

High oleic oils are very stable during heating and as such are great choices for cooking. 

What Cooking oil do you Recommend?

My recommendation for a cooking oil depends on your needs and how you’ll use the oil.   With the following information, you’ll be well prepared to select the healthiest cooking oil for your needs.

What to Consider when Choosing a Vegetable Oil?

There are a variety of considerations to take into account when choosing a vegetable oil.  There are some related more to the sensory and culinary quality of the oil and several related to the health attributes of the oil. All of the health characteristics of the oil are related to the fatty acids that make up the oil.

All vegetable oils are made up of fatty acids, just like all carbohydrate is made up of sugars and all protein is made up of amino acids. Fatty acids are the natural chemical components of oil. They are chains of carbons held together with either single or double bonds surrounded by hydrogen atoms. There are various ways to classify these oils.

While the difference in the chemistry of these fatty acid chains seem subtle, they change how they behave in our bodies, with some improving our health and some compromising our health.

This is my outline of the various considerations when choosing a vegetable or cooking oil, beginning with some of the culinary considerations then moving onto the health aspect and focusing on high oleic research. You can use this Table of Contents to help you navigate this blog post.

Vegetable Oil vs Cooking Oil

Vegetable oil means the oil is pressed from a plant seed, but if you see this on a food label it has come to mean soybean oil or a combination of soybean and other oils. The other oil in there can depend on where you live, in Canada this tends to be canola oil in the U.S. it might be corn oil. Typically vegetable oils are blends of different oils.

Cooking oil, includes any oil used for cooking, while this is typically a vegetable oil, it could also be an animal sources oil like lard, butter, ghee or tallow.

Vegetable oil front and back label
This bottle of vegetable oil contains canola and/or soybean oil.

Opinion on Cooking Oil. I prefer to buy single oils and not blends, that way, I know what I’m getting and how much (as the blends don’t tell you the % of each oil). I also prefer unrefined oils and cooking oils tend to be refined. My recommendation would be to look for a named vegetable oil and not “cooking oil”. Keep reading to find out more about why I recommend this.

Flavour of Vegetable Oils

In some cases, you may want to flavour of the oil to shine through and provide a distinct flavour note. For example, if you have some beautiful fresh bread and you want to make an oil and vinegar for dipping. In this case, you would want to use a flavourful oil like extra virgin olive oil.

Like wine tasting, olive oil, is given flavour attributes based on the sensory qualifies. A ‘fruity’ olive oil would have flavours like artichoke, grass and fruits. It can also have pungency like chili’s or black pepper and its third flavour note is bitterness, which comes from unripe olives and can be desired by some – it all depends on your preference.

Some oils are infused with different flavours. If this is the case, you may have several oils in your cupboard to work with different recipes. Be careful to buy these in small quantities if you are using them only for one or two recipes as oils can go rancid over time.

If you are baking some muffins and don’t want a heavy taste to ruin your recipe than you would choose an oil with a very light or neutral taste, which is also related to the level of refinement. The more refined, the more neutral the flavour (more on refinement below).

5 bottles of flavoured vegetable oil - truffle, garlic, basil, chilli and lemon
Some cooks like to work with flavoured vegetable oils such as truffle, garlic, basil, chili or lemon. Reading the label to determine the base oil, will give you the health attributes of the oil.

Opinion on Flavoured Oils: If you choose to use a flavoured oil, make sure you determine what the base oil is. Also, I suggest that the flavouring agents be natural and not synthetic. Since you may use these oils for a limited number of recipes, buy them in small quantities to prevent the oil from going rancid before you use it up.

Refinement of Vegetable Oils

Taste or flavour is very closely linked to the level of refinement. Most oils smell and taste like the seed they are pressed from, for example peanut oil smells like peanuts, sunflower oil smells like sunflower seeds.

But an oil can be refined or filtered. When this is done, the colour and flavour become more neutral. Loss of flavour can be desirable for some recipes, for example, think about baking muffins, you may prefer a neutral tasting oil for this. It can be heated to a higher temperature before it produces blue smoke (this is called the smoke point), but keep reading, because smoke  point doesn’t mean more stable.

The downside is that as well as losing flavour you are also losing some of the beneficial plant compounds from the original fruit or seed source. As well as affecting the taste, there is concern about the refining process, referred to as RBG which stands for refined, bleached, deodorized. This creates two issues.

Controversy exists about hexane which is one product of RBG processing which could remain in the oil in small levels, but credible source from the Harvard School of Public Health indicate that refined oils, contain low levels of residual hexane and that these levels are safe (1).

In Canada, the government allows a residue of 10 parts per million (ppm) of hexane in vegetable oils. Their study revealed that refined vegetable oils can contain 0.8 ppm, but they acknowledge, that if the oil is used for cooking, the hexane level would be even lower, as the hexane dissipates from the oil when heated above 68.7 °C (155.6°F) (12).

Sources from Berkeley Wellness adds, that if you choose to avoid oils in which hexane is used for extraction, you should look for terms such as “expeller pressed” or “cold pressed” on the label (11).

The second issue is that refined oils also contain higher levels of trans fats (see below) (3).

Bottle of unrefined Sesame oil
The bottle of sesame oil states it is “unrefined”.

Opinion on Refined Oils: While refined oils can still be considered safe, they do contain more trans fats (although that number is still small) compared to unrefined oils. While I trust Environment Canada when they set the safety limits for hexane, I still prefer to reduce my exposure, especially when it’s easy to do. If you prefer to limit exposure to hexane residue in your vegetable oils, then look for terms like  ‘cold pressed’, ‘unrefined’ or ‘virgin’ on the label.

Smoke Point of Vegetable Oils

The smoke point is the temperature of which an oil breaks down chemically due to heat and it will produce a continuous bluish smoke. The temperature when this occurs is dependent on the chemistry of the oil. Typically long chain fatty acids break down at a lower temperature (more on this below). The smoke point is not one set temperature, as the smoke point changes as the chemistry of the oil changes with heating.

While many websites say this is the “most important” consideration in choosing an oil, I do not agree. In fact, I think smoke point is one of the least important attributes.

Most of the clients and audience members that I work with tell me that when they cook, they use a medium-low heat. I do the same, that’s one reason why I think smoke point is not my deciding factor when choosing an oil.

2 bottles of avocado oil
Most oils do not list their smoke point on the label, but these two bottles of avocado oil do. One lists “smoke point 200 degrees C” the other states “high heat cooking oil”. While some people see a high smoke point as a reason to buy a particular oil, I do not.

The second, and arguably more important reason is that I don’t think smoke point is a good indicator of the health of the oil when heated. A study from researchers in Australia heated ten common cooking oils to 464° F (240°C) in a pan fryer and to 365° F (180°C) in a deep fryer. After several analyses of the oil they concluded: “the higher the smoke point, the more polar compounds that are produced” (3).

Polar compounds are unhealthy compounds produced from chemical changes due to heating the oil. They are associated with hypertension, Alzheimer’s and atherosclerosis, according to the Food Safety and Standards Authority of India (4).

It’s a big misconception that you can’t cook with olive oil, perhaps partially because many oil labels state “suitable for dressings and finishing”, but this may have more to do with taste and cost and not the smoke point (3).

Opinion on Smoke Point:  If you are choosing your vegetable oil based on the smoke point, I suggest you stop. The smoke point does NOT correspond to safety or stability of an oil (3). In my opinion, smoke point should not be your consideration when choosing a vegetable oil. Keep reading to find out what I think it should be.

Saturated Fats in Cooking Oils

To help you remember this, saturated starts with an “s” as does “solid” and saturated fats are solid at room temperature. For example butter, coconut oil and bacon fat are all solid at room temperature.

The chemistry of a saturated fatty acids, means that all of the carbons on the chain are saturated with hydrogens.

A carbon chain (C) saturated with hydrogens (H)
This is how a chemist sees a saturated fatty acid. The carbons in the chain (C) are saturated with hydrogens (H)

You can see that in this image where C=carbon and H=hydrogen.

That means that when you take a pound of butter out of the fridge and leave it on your kitchen counter, it doesn’t melt into a puddle, although it does soften, it retains its rectangular shape.

Just like that bacon fat that is left in the fry pan after you cook your bacon. When you let it sit, you will see that as the fat cools it turns white and solid. This is the reason you don’t pour this down the kitchen sink while it is still hot – because you know that once it gets down there, it will turn solid again and clog your pipes (at least I hope you know that now…so don’t pour bacon grease down the sink).

You also don’t want to consume too many saturated fats, as they will clog your arteries the same way they clog the kitchen pipes. This hardening of the arteries is called atherosclerosis . To keep your arteries soft and flexible and not hard and plaque-filled, then choose oils that are lower in saturated fats and high in unsaturated fats (2).

bottle of coconut oil
Coconut oil is solid because of its high content of saturated fat. In fact, it’s more saturated than butter. Saturated fats are linked to atherosclerosis and heart disease as well as inflammation.

Which ones are lower in saturated fats? As I mentioned earlier, butter, coconut oil and bacon contain saturated fats and you should limit these. Other sources of saturated fats are animal fats and tropical oils and examples include cream, cheese, meat fats and palm kernel oil.

For years, the promoters of coconut oil were unrestrained in their promotion of coconut oil, by claiming that, although coconut oil is high in saturated fat, it is a vegetable source saturated fat and therefore is not as damaging as the animal source saturated fats.

Fortunately, we finally have enough research for the American Heart Association to issue a statement on that. That statement is clear; “because coconut oil increases LDL cholesterol, a cause of CVD, and has no known offsetting favorable effects, we advise against the use of coconut oil” (2).

Opinion on Saturated Fats: Saturated fats are associated with Atherosclerosis and should be limited in the diet. While the only vegetable oil with saturated fat is coconut oil, you may see other saturated fats such as palm kernel oil as an ingredients in various foods. Be sure to read your labels! This doesn’t mean you can never ever use coconut oil again, but it should not be your main cooking oil.

Trans Fats in Vegetable Oils

Like all of these terms, ‘trans’ refers to the chemistry of the fatty acids chain. A trans fat has the hydrogens on opposite sides of the carbon (C) chain and a cis fatty acid has the hydrogens (H) on the same side, as in this image:

 
Cis and Trans chemical configurations
A Cis configuration has the hydrogens on the same size of the carbon chain. A trans configuration has the hydrogens on the opposite side. The trans fatty acid are the most unhealthy. Image: MUN IB

While this looks like such a small difference, this change in the location of the hydrogen changes how the fat behaves in our bodies. There are two main sources of trans fats in our diet; milk fats and vegetable oils.

Of the 10 oils treated in the Australian study I mentioned above (extra virgin olive oil, virgin olive oil, olive oil, canola oil, rice bran oil, grapeseed oil, coconut oil, high oleic peanut oil, sunflower oil and avocado oil) the grapeseed oil was the highest in trans fat before heating (3).

 

4 bottles of grapeseed oil
While grapeseed oil is often promoted because of its high smoke point. Of the 10 oils tested in one study, it was the highest in trans fat before and after heating (3).

Manufacturers used to create trans fats to make margarine. This was done by heating the vegetable oil and adding hydrogen gas. The result was that the oil became semi-solid, this type of oil is called “partially hydrogenated”. The partial hydrogenation process allowed margarine which was 100% vegetable oil and liquid to become a semi-solid and spreadable.

Unfortunately, partially hydrogenated fats are the worst type of trans fats. They are very unhealthy and have been shown to have a negative effect on our blood cholesterol levels to the point that as of September 17, 2018 the Canadian government banned them. You can read more about that in this document called Prohibiting the Use of Partially Hydrogenated Oils in Foods (6).

A fully hydrogenated fat, is a saturated fat and not a trans fat, and seems to be less harmful then partially hydrogenated fats (7). These oils have come to replace the partially hydrogenated oils since the ban.

But, trans fats can still be made from cooking in oil. Typically we think about deep fat fryers such as when making French fries and donuts. This is due to the temperature of the oil but also to the fact that the oil is used over and over again, and the oil remains hot for hours, both of which leads the oil to break down over time and the creation of trans fats and other harmful compounds such as polar compounds.

Unfortunately, we can also create trans fats when we cook with vegetable oil at home. In the Australian study, mentioned above, the refined oils tended to start out with more trans fats than non-refined oils (given that they are bleached and heated during the refining process).

The unrefined oils (extra virgin olive oil, virgin olive oil and avocado oil) had lower levels of trans fats before heating, created trans fats when the temperature was raised while the refined oils produced more trans fats by a longer duration of heating (3).

Bar graph showing the initial amount of trans fat, and trans after heating to 240 C and 180 C for 6 hours.
Grapeseed oil had the highest amount of trans fat to begin with and created the most with heating followed by canola oil (3). Oils are (left to right) extra virgin olive oil, virgin olive oil, olive oil, avocado oil, grapeseed oil, sunflower oil, rice bran oil, high oleic peanut oil, canola oil, and coconut oil. Link in image.

This chart shows amount of trans fats: initially, before heating in the (the black bars), after heating the oils to 365° F (180°C)  in a deep fryer for 6 hours (360 minutes) (the white bars) and after gradually raising the temperature of 1 cup of oil over 20 minus until it reached a temperature of  464° F (240°C) in a pan fryer and (the light bars).

Opinion on Trans Fats: While trans fats are banned and are no longer used to make margarines,  you can still consume them, whenever you eat foods cooked or fried in oil, as the oils produce trans fats when heated. Cooking with unrefined oils that are higher in antioxidants will produce fewer trans fats. Your safest bet is to cook with extra virgin and virgin olive oil, avocado oil as well as other oils high in oleic acid (keep reading).

Polyunsaturated and Monounsaturated

As I mentioned above, saturated fats are solid at room temperature and unsaturated fats are liquid at room temperature. The term “unsaturated” again, refers to the chemistry of the fatty acid.

Referring to the image below,  the top image shows one (mono means one) double bond between two carbons and therefore this carbon chain is not saturated with hydrogen. Because there is only one double bond, this is called “mono-unsaturated” fatty acid.

In the bottom image, there are two double bonds (or places of unsaturation) on the carbon chain (poly means two or more) this is called a poly-unsaturated fatty acid. While these seemingly small changes in the natural chemical scaffold of these oil components seem trivial, they actually make a difference in how this oil will behave in the body.

Chemical structure of poly and mono-unsaturated fatty acids
The polyunsaturated fatty acids has many (or more than 1) double bond in the carbon chain. The monounsaturated fat has 1 double bond in the chain. Both are healthy fats. Image credit Felicitas Mokumbo and Voster Muchenje (link in image). The image is from research entitled Producing Pork to Meet Modern Consumer Demands.

Monounsaturated fats in Vegetable Oils

A good examples of monounsaturated fats are olive oil, avocado oil, and oils labelled “high oleic” (more on this below) which are made up of fatty acids that are predominantly monounsaturated. The monounsaturated fat in olive oil is called oleic acid, and it referred to as an ‘omega-9 fatty acid’ (more on this below).

This chemical structure has a positive influence on health and it has been studied for years since the publication of the now famous Seven Countries Study. In this study, the diets of people from seven different countries (United States, Italy, Greece, Japan, Finland, the Netherlands and Yugoslavia) were compared to see which country’s population had the lowest rate of heart and blood vessel diseases (8).

The healthiest diet was found to be from the residents of Crete, Greece and that began ongoing interest in the traditional Mediterranean diet, usually shortened to the “Mediterranean diet” and the health benefits of olive oil. There is some misinformation afloat that you can’t cook with olive oil, but research which compares the stability of oils when heating challenges this misinformation with fact (3).

This article from USA Today reiterates that the smoke point of the oil, does not determine it’s stability when heating. In fact olive oil, being very high in antioxidants and monounsaturated fats, breaks down more slowly during cooking (5).

bottle of olive oil
Olive oil rose to prominence as a healthy oil with the publication of the 7 Countries study. Research to this day, continues to support the Mediterranean diet as a healthy diet.

Opinion on Monounsaturated Fats: Monounsaturated fats undergo fewer oxidative reactions during heating. Oils that are high in monounsaturated fats including extra virgin olive oil, virgin olive oil, avocado oil and the high oleic variants and are an excellent choices for a cooking oil.

Polyunsaturated Fats

These fats were considered very healthy and choosing oils with a high amount of polyunsaturated fatty acids was recommended as a good choice, but recently, new research has put this recommendation to the test.

Researchers from the University of Minnesota have heated polyunsatarated oils to 365° F (180°C) for as little as 3o minutes and documented the production of toxic compounds called HNE (4-hydroxy-trans-2-onenal) (17). Not only does the HNE form in the oil, but it is absorbed by the food that is cooked in the oil.

The HNE and related compounds are formed by the oxidation of the linoleic acid (see below) and is associated with atherosclerosis, stroke, Parkinson’s and Alzheimer’s, Huntington’s and liver disease (17).

One concern sighted by the Prof. Csallany of Minnesota is that oils that are reheated and reused are particularly troublesome. This let’s home cooks off the hook but is certainly a concern if you are eating fried foods when you eat out as reusing cooking oil is a common practice for restaurants that use deep-fat fryers.

Essential Fatty Acids

Included in the polyunsaturated family are the ‘essential’ fatty acids. This means that the body can not make these fatty acids and they must be consumed in the diet. The two essential fatty acids are called linoleic acid (LA) and alpha-linolenic acid (ALA).

While essential fatty acid deficiency is a theoretical risk, it is quite rare in healthy people. Signs and symptoms include dry, scaly skin, increased risk of infection, and poor wound healing. For best health, you should consume sources of essential fatty acids in your diet and these include flax, canola and walnuts (ALA) and safflower, sunflower and soybean oil (LA).

National Institute of Health Omega-3 fatty acid recommendations chart
The National Institute of Health recommends 1.1 grams per day for adult women and 1.6 grams for adult men. Image source NIH link in image.

You do not require a lot of oil to meet your requirements for essential fatty acids. The National Institute of Health has established Average Intakes (AIs) for alpha-linolenic acid (ALA) and that is 1.1-1.6 grams per day (see chart). One tablespoon of flax oil contains 7.26 grams, so less than a teaspoon a day will meet your needs.

 

For the essential fatty acid linoleic acid, the Average Intake is set at 11-17 g per day (14-17 g/day for males and 11-12 g/day for adult females) depending on age (4) will meet your requirements. But this fatty acid is found in many foods, so you don’t need to use an oil to get your requirements.

Omega-3 and Omega-6

The two essential fatty acids (ALA and LA) are also known as omega-3 (ALA) and omega-6 (LA).

Omega-3 Fatty Acids
chemical structure of omega-3 fatty acid compared to a saturated fat
The saturated fatty acid has all of its carbons saturated with hydrogen. An omega-3 fatty acid, has one double bond on the 3rd carbon from the omega end of the carbon chain. Image Credit Milk Genomics, link in image.

This again, refers to the chemistry of the carbon chain. A carbon chain has a beginning and an end, an “alpha and an omega”. When you count from the omega end of the chain, the 3rd carbon from the end has a double bond and this is known as an “omega-3”.

 

Opinion on Omega-3: You read a lot about the health benefits of the omega-3 fatty acids and that is because they have been shown to provide you with an improved cholesterol profile and more importantly, that omega-3 is a strong anti-inflammatory and a supporter of the immune system. You should aim to choose oils that have a high amount of omega-3 fatty acid especially for non-heating applications such as salad dressings and drizzles. But the polyunsaturated fats, don’t hold up as well to heating as the monounsaturated fats.

Omega-6 Fatty Acids

1 bottle of flax and 1 bottle of hemp oil
Hemp seed and flax oil are the oils that are highest in omega-3 fatty acid. But you can’t cook with these oils, only use them as a drizzle or dressing.

In contrast to omega-3 fats which seem to be all rainbows and sunshine, the omega-6 fatty acids, are more of an enigma. As I mentioned above, linoleic acid is an essential fatty acid, so you must consume it for optimal health. But since it has its double bond on the 6thcarbon from the omega end of the carbon chain, it has some properties that are less desirable.

Opinion on Omega-6: The main concern I have with omega-6 fatty acids are that they support inflammation in our bodies. Inflammation is an environment that is associated with cancer, atherosclerosis, metabolic syndrome and more so, while you can’t avoid omega-6 fatty acids because they are essential, you can limit your intake.

Seed Oil Variants

If you are a gardener, you will know there for every plant there are different varieties. If you want to plant some tomatoes in your garden, for example, there are several types to choose from. The same is true for seed oil crops. This is most important when it comes to seeds with high oleic oil versions.

Bottle of sunflower oil with the claim
This bottle of sunflower oil is labelled “source of omega-6 polyunsaturates”. Despite omega-6 being an essential fatty acid, I don’t suggest that this is a buying feature. We have enough omega-6 in our diet to meet our needs and these fatty acids are inflammatory.

High Oleic Oils and High Linoleic Oils

You may have never noticed this when you shop for vegetable oil, but some oils (usually safflower or sunflower) have a statement on their label about the amount of oleic acid in the oil, such as “mid-oleic” or “high oleic”.

Why Does the Oleic Acid level Matter? 

Oleic acid is a mono-unsaturated omega-9 fatty acid. This is the main fatty acid in olive oil and it’s what is responsible for its beneficial health properties; namely that it can help to lower LDL cholesterol (often called the “bad cholesterol”) and raise HDL cholesterol (often called the “good cholesterol”).

In addition, high oleic oils are more stable when heated. In fact, the U.S. Food and Drug Administration (FDA) announced in November, 2018 that there is enough data on the benefits of high oleic oils to allow a health claim on oils that have at least 70% oleic acid. This is one of the two health claims allowed:

“Supportive but not conclusive scientific evidence suggests that daily consumption of about 1½ tablespoons (20 grams) of oils containing high levels of oleic acid, when replaced for fats and oils higher in saturated fat, may reduce the risk of coronary heart disease. To achieve this possible benefit, oleic acid-containing oils should not increase the total number of calories you eat in a day. One serving of [x] oil provides [x] grams of oleic acid (which is [x] grams of monounsaturated fatty acid)” (13).

The high oleic oils, specifically mentioned in the petition to the FDA for this health claim are 1) high oleic sunflower oil, 2) high oleic safflower oil, 3) high oleic canola oil, 4) olive oil, and 5) high oleic algal oil (13).

Oleic acid is also contained in pecan, canola and peanut oil among others. You can remember it this way “Oleic” starts with an “O” as does “olive oil” and I find it’s easy to remember that olive oil is a good oil. Several cooking oils, have different versions. I’ll go through some for you.

Sunflower Oil

Bottle of sunflower oil labelled
This bottle of sunflower oil is labelled “mid-oleic”

According to the National Sunflower Association here are four distinct oil types produced from the various sunflower plants (19):

  1. High Linoleic Sunflower oil– 21% oleic acid. The traditional sunflower plant produced this oil. But it is declining in popularity.
  2. Mid-Oleic Sunflower oil (also called NuSun®) – 65% oleic acid. This is the most popular version of the oil and was developed through traditional plant breeding (this involved combining the pollen (male flower part) and transferring it to the pistil (female flower part) and creating a plant and harvesting the seed until a seed with a higher level of oleic acid was created (19).
  3. High Oleic Sunflower oil– 80% oleic acid. also developed through traditional plant breeding and growing in popularity.
  4. High Stearic/High Oleic (also called Nutrisun™) – 65% oleic acid (55-75% range). This is the newest version of sunflower and was also developed through traditional plant breeding. The oil from this plant is sought-after as a replacement for unhealthy partially hydrogenated vegetable oils (see trans fats above).
 

Opinion on High Oleic Sunflower Oil. Because of the high level of oleic acid, this is a healthy choice. It’s also appealing to many as it was created from traditional plant breeding and not transgenic engineering (more on this below). It may be hard to find in the grocery stores.

Safflower Oil

The safflower belongs to the same family as the sunflower (9). There are two main types of safflowers and safflower oil.

  1. High Oleic Safflower Oil–contains 70% or more oleic acid
  2. High Linoleic Safflower Oil – contains 70% or more linoleic acid

As I discussed above, while linoleic acid is an essential fatty acid, it is also an omega-6 fatty acid and therefore considered to be less desirable as it can contribute to chronic inflammation in the body. If you are using safflower or sunflower oil therefore, my recommendation is for you to choose one that is labelled “high oleic”.

bottle of high oleic safflower oil
This bottle of safflower oil, is labelled “high oleic” as well as organic and refined.

Opinion on high oleic safflower oil: Similar to high oleic sunflower oil, I think this is a good/healthy choice. As a bonus, the neutral flavour can be used for baking and other applications when you don’t want a strong flavoured oil. Your only issue may be finding it in your grocery store.

Canola Oil

According to the Canola Counsel, there are now two versions of canola oil;

  1. Commodity or classic
  2. High oleic canola oil – which contains 70% monounsaturated fats.

Only the classic is available for retail. The high oleic is sold to food companies and food service operations (9). This is encouraged in restaurant applications as the high oleic version has prolonged stability under high heat conditions, such as deep fat fryers.

Opinion on High oleic canola oil – since this is only available to food service operations, you won’t find this on grocery store shelves, but you can inquire when you eat out if they cook with high oleic canola oil.

Soybean Oil

American-grown high oleic soybean oil is now available. There are the three soybean varieties

  1. Conventional soybean oil with 23% oleic acid
  2. Vistive Gold high oleic soybean oil with 72% oleic acid
  3. Plenish high oleic soybean oil with 75% oleic acid

These new high oleic soybean oils are targeting the food service industry with their claims of “longest fry life of any edible oil” at 25 hours, neutral flavour, and long shelf life (14).

You might wonder, how the high oleic soybeans were produced and they are both made from transgenic technology (genetically modification), the answer is yes they are. As well as being high oleic, they are also resistant to the herbicide glyphosate, otherwise known as “round-up ready” (15).

Opinion on High Oleic Soybean oil: While this oil has the advantage of being high oleic, it isn’t available in grocery stores. Some consumes prefer to avoid foods that have round-up ready to reduce exposure to glyphosate residue. If this is you, you would have to ask when you order your food at restaurants to find out what kind of oil they cook with. But I suspect if you are ordering food that is cooked in a deep fryer, you aren’t too concerned about glyphosate residues.

Peanut Oil

According to the Peanut Institute, there are 2 types of peanut oil (16)

  1. Gourmet peanut oil. This is an unrefined peanut oil, and is considered a speciality oil. Which might explain why I’ve never seen it at a grocery store.
  2. Refined peanut oil. This oil is refined, bleached and deodorized and is used by fast food chains.

Peanut oil is naturally very high in oleic acid. According to researchers from the Czech Republic who analyzed the fatty acid composition is 71% oleic acid (18).

Opinion on Peanut Oil: If you are trying to reduce your use of refined oils, then you may not want this, but if you are choosing a refined oil, you might as well get one that is naturally high in heart healthy oleic acid.

Fatty Acid Chain Length

Thankfully, this aspect of the chemistry has terminology that is super simple to understand. The chain lengths are classified as short (less than 6 carbons in the chain) medium (6-12 carbons in the chain) and long (more than 12 carbons in the chain). While the length of the chain does affect how the fatty acid is absorbed and transported in the body, for most people this is not a concern.

There are some medical conditions that require medium chain fatty acids (called medium chain triglyceride or MCT oil).

What Medical Conditions Require MCT Oil?

The medical conditions that require a person to use MCT oil include;

  • Primary intestinal lymphangiectasia (Waldmann’s disease)
  • Chyloperitoneum (lymphatic fluid in the peritoneal cavity)
  • Gallbladder disease or removal
  • Gastrectomy (stomach removal)
  • Pancreatic insufficiency, small bowel resection (removal)
  • Lymphedema (read more about that in the blog post called Lymphedema Diet)

Opinion on MCT Oil: Promoting the health benefits of MCT for everyone (whether you require it or not) is one of the favourite marketing tools for promoters of coconut oil – since it has 64% MCT oil. But the downside to that, its that coconut is a very saturated oil which has been shown to increase your cholesterol level (14). So don’t fall for the hype of coconut oil. If you need a medium chain length oil then get pure MCT oil, introduce it into your diet gradually and don’t exceed 7 Tbsp per day. Also, you can’t heat this oil above 320 degrees.

Genetically Modified or Genetically Engineered 

This is an area which I find requires clarification of the terms, so let me do that before I begin. Technically, genetically modified can mean that a crop is modified by any means, included traditional plant breeding, whereas genetically engineered means that a novel product has been created by transferring genetic material from one organism to another.  Most people tend to use these terms interchangeably and also to say ‘genetically modified’ when they actually mean ‘genetically engineered’ and this can create confusion and misinformation in this area. There are vegetable oils that have been both genetically modified and genetically engineered. To be clear, traditional plant breeding including selection and hybridization are allowed in organic agriculture. Genetic engineering on the other hand, is not (10).

Oil crops that are approved for genetic engineering in Canada and the U.S. include canola, corn, soy and cottonseed. Canola and soy have been modified to be herbicide tolerant, which means the farmer can spray the entire field with a synthetic weed killer such as glyphosate, 2,4-D and dicamba and it will kill the weeds, but not the crop. Many have a concern about the remaining residue on these products after they are harvested. Corn and cotton have been modified to contain an insecticide; a gene from the bacteria Bacillus thurengiensis or “Bt” so that it kills common corn and cotton plant predators such as the corn bore and bollworm (11). Many are concerned about the harmful effect this has on pollinating insects.

Opinion on Genetic Modification and Engineering: Be precise when you speak about GM or GE and be careful not to confuse them. There is no reason to avoid crops developed from traditional plant breeding. Most people who a heightened concern about their health or the health of the environment choose to avoid oils made from GE crops, which I think is a prudent choice. If you are wanting to avoid this then choose organic canola or soybean oil. I don’t recommend corn oil…(because it’s high in omega-6 fatty acids)  but if you choose processed corn products like cereals, tortillas or corn meal, then look for organic or GM Free labels. To read more about GM crops, check out a previous Cancer Bites Blog post called GM-O or GM-No

Organic 

Choosing an oil labelled organic really has two potential benefits. The first and more obvious one is the benefit to the environment. When a crop is grown organically, the farmer uses only allowed inputs and cannot use synthetic chemicals, which have been linked to the creation of dead zones in our waters. The second benefit is to health. In this regard, I see a couple of benefits, one is that organic produce is lower in synthetic chemical residue and the second is that organic crops can be higher in beneficial plant nutrients (phytonutrients). While the Canadian government assures us that GE crops and the chemicals that are applied to them are safe, I know many cancer survivors like myself, prefer to err on the side of caution by limiting risk, even unproven potential risks.

Opinion on Organic: There are many organic seed oils available, but just because it’s labelled organic doesn’t mean it’s the best choice. The other information above still applies about choosing oils that are high in omega-3 fatty acid or oleic acid for the best health benefits.

Virgin 

Virgin oils are obtained, without altering the nature of the oil, by mechanical procedures, e.g. expelling or pressing, and the application of heat only. They may have been purified by washing with water, settling, filtering and centrifuging only (6).

Bottle of avocado oil that states
This bottle of avocado oil has several statements on the label in including; “expeller pressed” ,”high heat cooking oil” ,”high oleic/high monounsaturated”, “ideal for dressing, sauces and marinates” and “kosher”

Cold pressed 

Oils are obtained, without altering the oil, by mechanical procedures only, e.g. expelling or pressing, without the application of heat. They may have been purified by washing with water, settling, filtering and centrifuging only. No food additives are permitted in virgin or cold pressed oils (6).

 

Opinion on Virgin and Cold Pressed: If you are avoiding refined oils (which I suggest) then these are two terms to look for on your oil label.

Label Reading

 

I’ve shown you quite a few things when it comes to reading labels. I hope this helps you to feel confident in your choice and to switch up if you need to. Given all of this information on vegetable oils, my bottom line recommendations are:

  • For your main cooking oil choose extra virgin olive oill. It’s personal choice whether to choose organic or not. Olives are not genetically engineered or roundup ready
  • For a neutral tasting oil, for baking and other applications, choose a high oleic oil like sunflower or safflower
  • Read your labels

Other oils can be used for specific recipes but the two above should be your main oils.

 

References

  1. Crosy G. Ask the Expert:Concerns About Canola Oil. Harvard T.H.Chan School of Public Health. Last updated Dec, 2018.
  2. Sacks F, Lichtenstein A, Wu J et al. Dietary Fats and Cardiovascular Disease: A Presidential Advisory from the American Heart Association. Circulation. 2017 Jul 18;136(3):e1-e23.
  3. De Alzaa F, Guillaume C and Ravetti L. Evaluation of Chemical and Physical Changes in Different Commercial Oils During Heating. ACTA Scientific Nutrition Health. Vol 2 (6), June, 2018.
  4. Zaidi, A.  Can We Reuse Cooking Oil Once it is Utilized for Frying Foods? Food Safety and Standards Authority of India. May 8, 2017
  5. Fetter, K. Why You Should Stop Worrying About Olive Oil’s Smoke Point. USA News and World Report. Sept 27, 2019.
  6. Health Canada. Prohibiting the Use of Partially Hydrogenated Oils in Foods. Last update Set 15, 2017.
  7. Berkeley Wellness.  Ask the Experts: Hydrogenated Oils. Last update Oct 1, 2011
  8. The online Scientist. 7 Countries Study. https://www.sevencountriesstudy.com
  9. Canola Council. Classic and High-Oleic Canola Oils. Sept, 2007.
  10. Canadian Food Inspection Agency. Single or Multi-Source Vegetable Oils. Last Update, May 16, 2019.
  11. Berkeley Wellness. Ask the Experts: Hexane in Soy Foods. Last update May 1, 2012.
  12. Environment and Climate Change Canada. Screening Assessment for the Challenge Hexane. Last update, Feb 25, 2010.
  13. U.S.F.D.A. FDA Completes Review of Qualified Health Claim Petition for Oleic Acid and the Risk of Coronary Heart Disease. Nov 19, 2018.
  14. United Soybean Board. An Ingredient you Can Trust. 2020, Accessed Feb 19 2020.
  15. Purdue University, College of Agriculture. The Science of High Oleic Soybean Oil Regulation. Accessed Feb 19, 2020.
  16. peanut oil link – ADD
  17. Science Daily.  Food Fried In Vegetable Oil May Contain Toxic Compound.” ScienceDaily, 2 May 2005
  18. Orsavova J,  Misurcova L  Ambrozova J et al. Fatty Acid composition of Vegetable Oils and its Contribution to Energy Intake and Dependence of Cardiovascular Mortality on Dietary Intake of Fatty Acids. Int J Mol Sci. 2015 Jun; 16(6): 12871–12890.
  19. National Sunflower Association (U.S.) Four Types of Sunflower Oil. Accessed Feb 24, 2020.