Background

There’s a ton of conflicting advice and confusion on cooking oils and I will not claim that I am the subject matter expert on this topic.  The advice I share in this post is based on a combination of what I think are higher quality studies, common sense given the manufacturing process involved in making some of these cooking oils, and my own clinical experience in treating patients for over a decade with predominantly nutrition and lifestyle strategies, while tracking biological markers and symptoms. 

When people with a degree or who are a self-proclaimed expert based on extensive online research tell you that vegetable oils are healthy, keep in mind that they are citing dubious research that focuses on mortality and hard clinical endpoints like heart attacks.  Maybe you can argue in some of these studies that vegetable oils don’t increase heart disease risk and death rates, but in my clinic I’m seeing a growing number of other maladies like autoimmune disease, brain fog and neurodegenerative disease, chronic fatigue and more.  Some, but not all of these symptoms and conditions can subside and even reverse when patients undergo an “oil change.”  My goal isn’t for patients (and myself) to just live longer…it’s to live better.  

Since cooking oils make up such a fundamental part of our daily diet, including the oils present in most packaged food products, I want to start off by explaining some of the science behind cooking oils and their derivative fatty acids.  Many of my patients are resistant to making changes in their oils due to factors like flavor and price, so it’s worth understanding this science so you make the right choices.  If you’d rather skip the science, which I don’t recommend, you can head towards the end of the post where I provide some practical recommendations on cooking fats based on scientific studies and my clinical experience.

Why Do Cooking Oils Matter?

There are 2 important reasons the oils you cook with matter:

  1. Your Brain is Mostly Fat:  Your brain is nearly 60 percent fat, and the fats you put inside your mouth will have some influence on the fat composition of your brain.  When my patients tell me they can think more clearly, their memory and even their mood improves as a result of a fundamental shift in the types of oils and fats they eat and cook with, it’s because they are gradually rebuilding their brain so it can function at a more optimal level.
  2. Your Cell Membranes are Half Fat:  The cell membrane that serves as an outer wrapping for each of our cells is arguably the most important cellular structure given its myriad functions and it being the layer where our protein receptors reside.  I strongly recommend you review the initial part of my Omega 3 post here, titled “Our Magical Cell Membranes,” where I more specifically explain, with images, the role of our cell membranes in critical functions such as proper insulin receptor activity.  Just like the brain, the fats and oils we consume impact the structure of these membranes and can not only influence the function of the cells, but also how susceptible the cell is to chronic inflammation, a root cause for most chronic diseases.

I often have patients who complain about the price of high quality cooking oils. I have to remind them that the most important organ in our body, our brain, and the most important structure in our cells, the cell membrane, are impacted by the oils we consume.

The families I care for use these oils to cook foods not just for themselves, but for their children.  If parents can spend so much on school and extracurricular activities promoted to make their kids smarter, why would they compromise an essential building block that could potentially improve brain function, mood and overall health.

Chemistry of Fatty Acids in Cooking Oils

I’m using cooking oils and fatty acids interchangeably, since cooking oils are basically defined by the predominant fatty acids they contain.  So what are fatty acids?  Fatty acids are the building blocks of the fats in our body.  They are long linear strands of carbon atoms bonded together with hydrogen atoms coming off the sides, and the various other atoms (Oxygen, Hydrogen, Carbon, etc.) hanging off the ends.  See the image below:

Saturated and unsaturated fat

Notice the long spine of C-C (carbon-carbon) bonds running from east to west, the H atoms coming off the sides, and in this case the left end of the fatty acid has a specific cluster in red characterized by an oxygen attached by a double bond (looks like an “=” sign) and an O-H group.

Why is the top one called “saturated” and the bottom one “unsaturated?”  These terms are very confusing, but just think of the term “unsaturated” as being synonymous with having a double bond (“=” sign) along the carbon-carbon chain.

Now look at the top saturated fatty acid.  Do you see any double bonds connecting the carbon atoms?  If you do, you’re seeing double!  There are none and that’s why it’s called a saturated fat.  Not because it saturates your arteries, but because all the carbon-carbon links are “saturated” by single bonds.  Read my older post titled “why saturated fat is feared” so you understand the 3 reasons saturated fat gets such a bad reputation.

Now look at the bottom fatty acid.  Recall I said “unsaturated equals the presence of a double bond” somewhere along the carbon-carbon chain.  Do you see one?  Yes!  If you travel 3 Carbons west from the Hydrogen (H) hanging on the right end of the unsaturated fat chain, you’ll see it’s double bonded to another carbon.

I hope that’s clear.  The rest is easier.  Now that you know that the word “unsaturated” means a double bond is present, how many double bonds are there in a monounsaturated fatty acid?  The answer would be one, given the root word “mono.”  The most famous monounsaturated fat is oleic acid, the predominant fatty acid in our beloved olive oil.  A core component of the heart-healthy Mediterranean diet is thought to be the abundance of monounsaturated fats like olive oil (and olives), nuts and seeds.

How many double bonds would you find in a polyunsaturated fatty acid?  The answer would be more than one.  The polyunsaturated fats are further broken down into the Omega-3s and Omega-6s.  Omega-3s are found in marine sources like fish and plant sources like flaxseed and chia.  Read this post for details on Omega-3s which I won’t cover here.  Bottom line is that most individuals are consuming too little Omega-3s in their diet and too many processed Omega-6, which comes primarily from vegetable oils like soybean, corn, and canola oil.

Before I define which oils I think should be prioritized in the diet and why, I need to address the controversial area of Omega-6 oils like canola.  There are many distinguished scientists who do believe that vegetable oils like canola are heart healthy and lower cholesterol.  I do have to admit that today’s generation of oils like canola appear to be healthier than its predecessors because they have been chemically modified to include a higher percent of oleic acid, which is the core component of heart-healthy olive oil.

However, I still think of cooking oils like canola oil as being a highly processed food given the number of steps it takes to extract oil out of its seed.

If you don’t believe me, just watch this 5 minute Youtube video to understand the steps involved in extracting oil from a canola seed, which includes the addition of solvents like hexane, which is derived from petroleum and crude oil and used as an industrial cleaner. 

Again, scientists can point out multiple studies that support canola and other Omega-6 vegetable oils as neutral or possibly heart healthy, but I still have concerns about the amount of processing involved and think there are far less processed, healthier alternatives which have even more scientific evidence for lowering heart disease risk and extending lifespan, like olive oil.  Now let’s move on to the part you’ve been waiting for which are my recommendations for which oils to cook with.

Preferred Cooking Oils

Below are some of my thoughts and recommendations on cooking oils.  I’ve been asked on several occasions to write a post on my recommendations and if it was easy, I would have written it years ago.  Despite some general recommendations, you will see that like most things in nutrition, there is some degree of personalization that’s necessary.

Some general terms to be aware of for many of the oils listed below include:

Organic vs Non-organic:  Organic is sourced from clean sources without chemicals such as pesticides.  Choose organic over non-organic whenever possible

Refined vs Unrefined (aka Raw or Virgin):  Refined means the oil source (olive, coconut, etc.) has been processed using chemicals and solvents.  Unrefined (raw or virgin) means the source (olive, coconut, etc.) is just pressed to extract the oil, but no additional chemicals or solvents are used.  Olive oil is further categorized as extra virgin or just virgin (see below), while for coconut oil there is no difference between extra virgin and virgin.  Either one is unrefined.  Choose unrefined/raw/virgin whenever possible.

Cold vs Expeller Pressed:  Cold-pressed means the oil is pressed at lower temperatures which helps the oil retain more nutrients than expeller-pressed which is pressed at higher temperatures.

Smoke Point:  This is the temperature at which an oil on the pan or grill starts to burn and smoke.  You do not want your oil to burn and smoke because that’s when it becomes chemically denatured and starts releasing byproducts that cause oxidation and inflammation in the body.

Monounsaturated Fats

Olive Oil

Extra virgin olive oil, which I’ll refer to as EVOO, is a great oil for dressings, sauces, and even cooking.  Unlike the processing involved with Omega-6 oils like canola mentioned previously, this oil is just mechanically pressed and extracted from olives.  No additional processing or solvents used.  You’re literally just “juicing” the olives for oil.

There is abundant scientific data on its beneficial effects on heart health and cholesterol, insulin resistance, high blood pressure, and other conditions.  More than these studies, I’m even more persuaded by the quality of life and longevity of traditional Mediterranean populations who consume abundant amounts of olive oil.

Apart from the predominant monounsaturated fats in olive oil, I think their real health and longevity impact come from its incredible blend of anti-inflammatory/antioxidant compounds like tocopherols, B-carotene, lutein, phenolic acids, and more.

Keep in mind that most studies show that the primary benefit from adding olive oil to the diet comes when you replace some portion of your saturated fat intake with monounsaturated fats.  Adding olive oils to a diet already high in saturated fat may not have the same impact on cholesterol and other health measures.  However, keep in mind that in most nutrition studies when they refer to “saturated fat,” they are talking about low quality, processed sources of saturated fat.  It’s not clear what the impact on overall health would be of adding olive oil to a healthy diet with high quality saturated fat in moderation.  We’ll cover saturated fat next.

The real challenge is finding high quality olive oil that is not adulterated and contains a therapeutic amount of anti-inflammatory compounds.  There is a troublesome black market of olive oils on the shelves that do not represent the authentic oil with all of its antioxidants and related health benefits.

I recommend you check out a 3rd party site like consumer lab that tests these oils to find high quality brands.  As of the writing of this post, consumer lab’s highly rated brands include Kirkland’s (Costco brand), Newman’s Own, Bertolli, Colavita, California Olive Ranch and Trader Joe’s in terms of content of antioxidants and healthy monounsaturated fats.  Keep in mind ratings are subject to change.

EVOO (like all cooking oils) should be stored in dark, airtight containers in a relatively cool environment (dark glass or stainless steel containers work well).  Heat, oxygen, light, and time are some of the top enemies that can cause olive oil to spoil.  After opening EVOO, the typical shelf life if kept under optimal conditions is around 20 months.

EVOO used to be considered a relatively weak oil not appropriate for most cooking due to a low smoke point.  However studies now show that EVOO can be used to cook at a temp range of roughly 375-400 deg F.  The antioxidants in EVOO that I mentioned before actually help prevent oxidation and damage to the fatty acids up to this temperature range.

Using the oil terminology we covered earlier, buying cold pressed, EVOO, especially a vetted brand like we discussed, would be an excellent choice.  It doesn’t need to be labeled organic, since the Extra Virgin labeling does ensure high quality sourcing.

Unlike EVOO, olive oil that’s just labeled “virgin,” does not meet the high quality standards due to some defects in aroma and flavor, so it’s less expensive.

If we go lower down the olive oil food chain, you’ve got “pure” olive oil (may be labeled as just olive oil) which is a lesser quality, cheaper version of olive oil that is a mix of virgin and refined (processed) olive oil that is more heat stable and can be used to cook at higher temperatures.  It’s essentially an all purpose cooking oil.  Extra light also falls into this category (refined blended with some virgin), but the “extra light” refers to the color and flavor, not the calories.

Avocado Oil

This is the other popularly used monounsaturated fat.  It’s even more heat stable than olive oil with a smoke point up to 520 deg F, and also contains additional nutrients like vitamin E.  One study showed that avocado oil reduced the after meal rise in glucose, insulin, total cholesterol, LDL cholesterol and inflammatory biomarkers like CRP.  Like olive oil, the unrefined version is unprocessed, while the refined version uses heat and possibly chemical solvents to extract the oil.

Avocado oil is not typically labeled as being virgin or extra virgin.  This is a very specific standard used for olive oil.  Once again, you would want to use the highest quality, least processed brand.  I used to use Chosen Foods Avocado oil which is described as 100% pure avocados, expeller pressed and then “naturally refined.”  I’m not clear what the exact refining process is, but it can’t be as harsh as what’s used for seed oils since avocados, like olives, are pretty naturally oily.  Now expeller pressed recall means there is heat/friction involved in processing, although Chosen Foods says they use a proprietary lower heat technique.  I’m not sure what that is, but I’m not going to get too nit picky here.

More recently I’ve opted for using  Primal Kitchen avocado oil  made by my good friend and publisher, Mark Sisson.  This oil is cold (not expeller) pressed. I have a slight preference for the flavor as well.  There are a growing list of other high quality manufacturers out there making organic, cold pressed avocado oil.

Macadamia Nut Oil

I don’t use this oil, but it has an even higher concentration of monounsaturated fats than olive oil and does have a rich array of antioxidants.  However it lacks the long-term scientific data of olive oil and the price makes it prohibitive.

Saturated Fats

General Points about Saturated Fat

Saturated fat is a controversial topic that I’ve covered in prior posts.  My general thought based on the research and my clinical experience is that for most individuals it is relatively neutral, meaning it doesn’t really raise heart disease risk and cholesterol, but it is also not proven to be as heart protective as oils like EVOO.

However, there are definitely individuals in whom saturated fat increases cholesterol, particularly LDL cholesterol levels, and may contribute to weight gain as well.  Some of this is individual genetic tolerance to saturated fat.  For others it must simply be acknowledged that saturated fat is a high octane, high energy fuel source designed for active human beings who are generally metabolically healthy and are eating an otherwise healthy diet.

For example, many proponents of saturated fat and the keto diet are typically lean and active individuals, not sedentary, overweight office workers who rarely exercise.  I have many patients who fit the latter profile who read a headline that ghee or coconut oil is healthy and unfortunately they add this liberally onto their already unhealthy lifestyle.

In sedentary individuals with issues like insulin resistance, the mitochondria, which are the engines inside our cells, neither have the demand for such a high energy fuel source like saturated fat, and often do not have the metabolic machinery to convert such fuel into energy.

As a result, the saturated fat instead gets stored as body fat, gets converted to blood cholesterol, and/or can get converted to toxic lipid intermediates that can provoke insulin resistance.  As much as we talk about carbs and sugar as being the primary cause of insulin resistance, excess saturated fat in the wrong individual can be a trigger as well.  For most individuals, you cannot just keep adding more and more jet fuel (saturated fat) to a mini-van that’s mostly parked in the garage (sedentary, overweight, metabolically unhealthy human).

The good news is that as individuals get physically active, as they lose weight, and their metabolic profile shifts to a more fat-burning mode, their body is better equipped to handle saturated fat.  For example, as your aerobic fitness and strength improves with exercise and as your replaced processed foods and oils with natural, nutrient dense alternatives, your mitochondria may be able to now handle a little more saturated fat for fuel.

I also would not rely completely on genetic and microbiome testing to determine if you can handle saturated fat or not.

The science is too premature and genes in particular only indicate your metabolic tendencies and are by no way determinant factors.  For example, I have had patients whose genetic profile states they are not able to metabolize saturated fat well, but because they are physically active with excellent mitochondrial function, they have no problems using saturated fat for fuel.  In this case, I’m not going to use their genetic or microbiome results to say…”sorry, coconut oil is a banned substance for you.”  The converse is also true.  Your genetics may indicate you are an excellent saturated fat metabolizer, but because you eat a poor diet and are inactive with weak mitochondrial function, saturated fat can cause significant cholesterol abnormalities and weight gain.

If you are unsure whether your body can handle saturated fats like ghee and coconut oil, simply monitor your body weight and cholesterol (especially LDL cholesterol) while adding or removing these fats to see how your weight and cholesterol results respond.  If you are struggling with high LDL, check out my LDL case file here and download my free e-book called Cholesterol Decoded.

Butter

This is the classic cooking saturated fat.  Above disclaimers apply, so beware of you are eating lots of butter and are struggling with high LDL cholesterol and/or difficulty losing weight.  Choose organic, grassfed butter when possible.

Ghee

Ghee is a form of clarified butter made by slowly simmering regular butter into its liquid form and separating out the milk solids.  This means it contains less lactose than butter and other dairy products and is often well tolerated in individuals who have lactose intolerance.

Ghee also does contain vitamin E, antioxidants, and butyrate which is a short chain fatty acid (also found in butter) that can have beneficial effects on gut health and inflammation.  Ghee is a cooking fat and healing agent that has been part of Indian Ayurvedic therapies and ancient rituals dating back 5,000 years ago.  It also has a high smoke point of up to 480 deg F, which makes it an excellent choice for high temp cooking.

In my experience, I have not seen adverse effects in most of my patients using ghee in moderation.  I did already discuss in my prior disclaimer that sedentary, metabolically unhealthy individuals might have increases in body weight and lipids if they are overdoing ghee.

The quality of the ghee depends on the quality of the milk it is sourced from.  Ghee is quite simple to make at home, in which case you would choose organic, grass fed milk.  If you buy it ready made, then choose organic, grass-fed ghee and there are multiple manufacturers who make this given the huge global demand for ghee.   If you are buying ghee from India or from Indian stores in the US, you need to beware of the risk of “fake ghee” made from full or partially hydrogenated vegetable oil, aka vanaspati or vegetable ghee.

I know there is a big cost difference, but remember what I said early on in the post.  Don’t compromise with fats and oils, especially ones you use on a regular basis, since they contribute to the health of your brain and cell membranes.  For my older post on ghee, which includes a recipe for making ghee at the end, go here.

Coconut Oil

I did a dedicated post on coconut oil here.  Despite it being a saturated fat, it also contains medium chain triglycerides (MCTs) which are a direct energy source and less likely to be stored as body fat, unlike long chain triglycerides.  I would apply the similar saturated fat disclaimers to coconut oil in regards to LDL cholesterol and weight gain if used too liberally in sedentary individuals.

Choosing the right coconut oil is similar to olive oil.  The primary difference is that for olive oil the designation of extra virgin is superior to just virgin.  For coconut oil they are the same, so you can choose virgin or extra virgin.

Polyunsaturated Fats

Recall we mentioned that polyunsaturated fats come in the omega-3 and omega-6 varieties.  Omega-3s are not used to cook, so we will focus on the omega-6s.  Common omega-6 cooking oils include soybean, cottonseed, sunflower and corn.

As I mentioned earlier, there are prominent researchers who state, based on large studies, that replacing saturated fat with these types of vegetable oils lowers heart disease risk.  This might be true, but there are a few points that makes me question this conclusion:

  • The conclusion is based on nutrition studies which are inherently flawed with multiple confounders like recall bias and healthy user bias
  • The saturated fat cited in these studies comes from poor quality sources (processed meat, dairy, etc.).  These are not healthy, active individuals who are using high quality saturated fats in the context of an optimal lifestyle plan.  Saturated fat eaters in these studies were also more likely to engage in other unhealthy behaviors like smoking, inactivity, increased intake of sugar, etc.
  • It is extremely difficult to make the conclusion that a switch from saturated fat to polyunsaturated fats led to a decline in heart disease rates because during the same time there has been significant progress in cardiovascular medicine with drugs and procedures that have reduced cardiovascular disease onset and increased survival
  • Traditional Mediterranean populations have thrived in every area of health with diets rich in monounsaturated fats, while traditional Indians have been using ghee for thousands of years prior to the onset of modern lifestyle risks.  Modern humans raised on seed oils may be living longer due to advances in medicine, but they continue to be sicker and more obese.  I know there are multiple contributors to this, but it’s hard for me to think that omega-6 oils, which are ubiquitious in the food supply, are not playing a role.
  • There is absolutely no doubt that omega-6 oils are a processed food, and it’s hard for me to accept that an oil that undergoes so much processing can be good for health.
  • Most seed oils come from genetically modified sources, unless specifically labeled non-GMO.
  • I have clinical experience, as do many of my colleagues, where a singular shift in cooking oils from omega-6 oils to monounsaturated fats and limited amounts of healthy saturated fats led to definite improvements in symptoms, a reduction in inflammation, and often improvements in biomarkers

Having said all that, the good news is that today’s versions of omega-6 oils like canola are being manufactured to have a higher oleic acid content to more closely resemble the composition of monounsaturated fats.  They also are more heat stable and less likely to oxidize under high heat.  Yet they still don’t have the incredibly rich array of antioxidants as olive or avocado oil.

If you are cooking in bulk for an occasion and don’t want to spend extra on EVOO or Avocado oil, then using a high oleic acid content canola should be fine, but I hesitate to use these as staple daily cooking oils when we have what I consider healthier and time-tested alternatives.

Finally, do keep in mind that even though we are talking about cooking oils in this post, omega-6 oils like soybean, safflower, and canola are found in nearly every packaged food you come across.

If you like eating in restaurants or ordering out often, keep in mind that even though you may be ordering “low carb” or what you think are healthy meals, they are typically cooked in the lowest quality oils which are often reused over and over, turning them into even more inflammatory and oxidative fats (similar to trans fats) that can damage your cells and increase the risk of chronic disease.

One of the top reasons most of our meals are home prepared is because we have complete control of the oils and fats that go into cooking them and they are never recycled/reused.

Flavoring Oils 

The next few oils listed are what I call “flavoring oils” which impart unique flavors for more specialized dishes.

Mustard oil

Mustard oil is typically used in South Asian cuisine and provides a unique, bitter flavor to dishes.  It is rich in monounsaturated fats, but not as high as olive or avocado oil.  Unfortunately, there are animal studies that indicate a chemical in mustard oil, called erucic acid, may cause heart defects and nutritional deficiencies.

Based on this, the FDA does not recommend its use as an edible vegetable oil as shown here and it has also been banned for edible consumption in the EU and Canada.

If you do desire the flavor of mustard in your dishes, you can use mustard powder, which is generally regarded as safe for consumption and is what we use to make certain Indian fish dishes and curries.

Peanut oil

Peanut oil, like avocado and olive oil, is also relatively rich in healthy, monounsaturated fats in addition to omega-6 fats.  It is a popular oil used in East Asian cooking, providing a nutty flavor to dishes.  It is also relatively heat stable up to 450 degrees so is used in high temperature cooking and deep frying.

Peanut oil does have some of the overlap benefits of olive oil in regards to potentially lowering cholesterol levels, but I would still reserve it for specific dishes that warrant its use, rather than use it as a staple daily cooking oil.  I think olive oil and even avocado oil have a better nutrient density profile and a longer track record of studies to support their health benefit.

Sesame oil

Sesame oil has a good number of scientific studies to support its nutritional benefits.  It has high antioxidant activity and its anti-inflammatory action has been used therapeutically in Chinese medicine for joint aches and pains.  Sesame oil is also relatively rich in healthy monounsaturated fats and has a smoke point up to 400 degrees.  Sesame oil has a wonderful flavor used in Asian and Middle Eastern dishes.  Based on available data, I consider sesame oil a healthy choice for cooking oils that ranks closer to EVOO and avocado oil.  I personally use it mostly as a finishing oil that I drizzle onto Asian stir-fries, rather than cooking directly with it.

Air Frying

Air frying is a wildly popular trend.  The good news is that you use significantly less oil when using an air fryer.  The bad news is that cooking meats at high temperature that are not exposed to moisture will still cause chemical changes that produce byproducts that are potentially cancer-causing.   Steaming or slow-cooking meats in liquids (like an Instapot), would be preferable to minimize production of these dangerous compounds.

Using an air fryer for occasional snack items is fine and much more preferable to deep frying, but if you’re using it daily to fry meats and crispy appetizers and sides, do not think you are doing your body any favors.  I have many patients and friends who use these fryers every single day and I would not recommend that.  When you are using the air fryer, choose one of the healthy oils I recommended above with a higher smoke point like avocado oil.

Conclusions

We covered a lot in this post, but hopefully you have a deeper understanding about the science and significance of cooking fats.  To really distill this information into a few practical points:

  • Buy the best quality cooking fats and oils you possibly can, since they can impact your and your family’s brain and cell membrane health.
  • EVOO is an excellent, heart healthy oil for dressings, sauces and most cooking that does not exceed 400 deg F.
  • Avocado oil is an excellent, nutrient dense, relatively neutral tasting oil for higher temp cooking up to 520 deg F.
  • Saturated fats are acceptable in moderation for most individuals, but should be well sourced.  Individuals with difficulty losing weight and/or high LDL cholesterol who have been consuming lots of saturated fat should cut back or eliminate and replace with the monounsaturated fats (evoo, avocado).  Otherwise saturated fats like ghee and coconut oil are heat stable for high temperature cooking and may have some potential health-promoting properties.
  • Omega-6 cooking oils are evolving and improving in quality due to higher oleic acid content, but I still consider them inferior and not nearly as time-tested as the other fats mentioned.  Using it occasionally should be fine, but I don’t endorse them yet as a staple daily cooking oil.
  • Keep in mind that restaurant foods, packaged foods and many “health foods” are loaded with processed omega-6 cooking oils.  Stick to eating fresh, home prepared meals and snacks as often as possible.