How to Choose a Cooking Oil

Disclaimer: This is not medical or personalized nutrition advice, but general education. Discuss your own nutrition needs with your healthcare provider or qualified nutritionist.

So…it’s time to cook some veggies. You want to stir-fry, roast, or sauté them, and you need a bit of oil to get a desirable texture and flavor.

But which one do you pick?

olive-oil

Here’s a guide to choosing an oil, based on 3 essential concepts (in order of importance): temperature, nutrition, and flavor profile.

Temperature

Every cooking oil has a specific smoke point. The smoke point is the temperature at which the oil begins to brake down into fatty acids and glycerol, leading to a smoky byproduct that seems to find every distant smoke alarm no matter how careful you’ve been.

At this point, significantly more toxic fumes (polycyclic aromatic hydrocarbons and heterocyclic compounds) are emitted, and you inhale them if you’re standing over the stove. These molecules are carcinogenic and mutagenic, meaning that they promote the development of mutated and potentially cancerous cells. Repeated exposure to these fumes increases risk for rhinitis, pneumonia, and respiratory cancer, which is why proper overhead ventilation is a good idea. Also, cooking with oil this hot can cause a fire…which is why your smoke alarm goes off.

Fortunately, we have information from scientific research to tell us how high the oil can be heated before it gets to the smoke point. In general, more refined oils have higher smoke points because impurities and variations in fatty acids have been removed. Be aware that the oil’s smoke point is reduced the longer it is heated or if any food particles contaminate it, so you’ll need to keep an eye on the third batch of Brussels sprouts if you’ve cooked it in the same oil.

Smoke Points

  • Refined avocado oil - 520°F

  • Refined safflower oil - 500°F

  • Refined sunflower oil - 485°F

  • Ghee/clarified butter - 450-475°F

  • Refined coconut oil - 450°F

  • Rice bran oil - 450°F

  • Semi-refined sunflower oil - 450°F

  • Refined peanut oil - 450°F

  • Refined corn oil - 450°F

  • Semi-refined sesame oil - 450°F

  • Refined soybean oil - 450°F

  • Palm/palm kernel oil - 450°F

  • Hazelnut oil - 430°F

  • Almond oil - 420°F

  • Grapeseed oil - 420°F

  • Virgin olive oil - 410°F

  • Refined olive oil - 390-470°F

  • Low acidity extra virgin olive oil - 400°F

  • Semi-refined walnut oil - 400°F

  • Refined/expeller pressed canola oil - 375-400°F

  • Macadamia nut oil - 390°F

  • Unrefined coconut oil - 350°F

  • Unrefined sesame oil - 350°F

  • Red palm oil - 350°F

  • Hemp seed oil - 330°F

  • Extra virgin olive oil - 320°F

  • Unrefined peanut oil - 320°F

  • Unrefined canola oil - 225°F

  • Unrefined/cold-pressed sunflower oil - 225°F

  • Unrefined flaxseed oil - 225°F

  • Unrefined safflower oil - 225°F

  • Toasted sesame oil - 225°F

Typical Cooking Temperature

Pan searing: 500°F

Baking: 325-425 °F (depending on food density)

Frying: 325-375 °F

Sauté on stove: 300-320 °F

Pressure cooker: 250°F

Boiling/simmering: 212°F or just below

Some knowledgable souls will be disgruntled that I think temperature is the most important aspect of choosing a cooking oil. The truth is, fat quality is very important, but it won’t matter how nutritious it is if you burn it!

Nutrition

Cooking oils are pure fat. That shouldn't scare you, because your brain is almost 60% fat and needs specific types of fat to function. It makes sense, then, that the types of fat you eat have a huge impact on your health. I often discuss fat quality with my clients because they tend to focus on quantity.

Main types of fats in cooking oils

  • Omega 3

  • Omega 6

  • Omega 9

  • Saturated fat

These fats are categories, and each category has one or more type of fatty acids. If you see names like stearic acid, palmitic acid, or oleic acid on a food label, know that those are just subcategories of these major types of fats.

 
salmon-omega-3-fatty-acids

Omega 3 fatty acids

Omega 3 fatty acids are necessary for nervous system formation and function, which is why DHA supplements are recommended for prenatal health. Many omega 3s reduce inflammation in joints, improve metabolic function, and prevent autoimmune disease by optimizing the immune system. These are essential fatty acids, meaning the body does not produce them and you must get them through food or supplementation.

hemp-seeds-omega-6-fatty-acids

Omega 6 fatty acids

Omega 6 fatty acids support tissue growth and cellular repair, and modulate inflammation. Omega 6s are also essential fatty acids, and the body requires a moderate amount to function normally.

The brain (and other organs) works best when the ratio of omega 6 to omega 3 fatty acids in red blood cells is 4:1 or lower. North Americans tend to have a 20:1 ratio (or higher!), which is associated with inflammatory conditions such as cancer, rheumatoid arthritis, and asthma. If you would like to improve your own 6:3 ratio, choose oils with higher omega 3 content.

 
omega-9-fatty-acids

Omega 9 fatty acids

Omega 9 fatty acids are an important fat source for overall health. They raise HDL cholesterol, lower, LDL, reduce joint inflammation, support immune function, and decrease risk of breast cancer. Oils that are primarily monounsaturated fats also tend to have high amounts of vitamin E. You may want to choose oils high in omega 9 if you are concerned about any of these issues.

 
coconut-saturated-fat

Saturated fatty acids

Saturated fats are components of hormones, line cell membranes and support cellular signaling, and regulate immune function. While scientific studies are controversial, it seems that genetics plays a large role in determining how your body reacts to saturated fats. Just remember that saturated fat is necessary and should not be vilified; however, you need more mono- and polyunsaturated fats in your life.

Unfortunately, the oils used in commercially prepared food are often the least nutritious. If you eat anything fast-casual, shelf-stable, or deep fried, it was likely cooked in refined or hydrogenated oils that are high in omega 6 fats and/or trans fats. Hydrogenation can’t happen in home cooking, so it’s nothing you have to worry about when selecting oils. However, you should know that many vegetable oils used in commercial cooking have been partially hydrogenated to improve stability, and become trans fats. Trans fats are not digestible, which is why eating fried food can cause diarrhea.

Higher levels of polyunsaturated fats (omega 6 and omega 3) indicate more rapid oxidation, which is why oils with more polyunsaturated fats have lower smoke points. Monounsaturated fats (omega 9) are much more resistant to oxidation, which is why oils primarily made of monounsaturated fats have higher smoke points.

Omega 6:3 Ratio

Use this list to choose oils with the best omega 3 content in comparison to omega 6. Keep in mind that some of these oils have very little omega 3 or 6, but the ratio is good.

  • Unrefined flaxseed oil - 1:4

  • Macadamia nut oil - 1:1

  • Expeller-pressed canola oil - 2:1

  • Refined canola oil - 3:1

  • Hemp seed oil - 3:1

  • Semi-refined walnut oil - 5:1

  • Avocado oil - 12:1

  • Rice bran oil - 21:1

  • All olive oils - 13:1

  • All peanut oils - 32:1

  • All sunflower oils - 40:1

  • Unrefined sesame oil - 42:1

  • Palm/palm kernel oil - 46:1

  • Refined safflower oil - 133:1

  • Refined/semi-refined sesame oil - 138:1

  • Grapeseed oil - 676:1

  • Ghee/clarified butter - 0:0 (no omega 3)

  • Hazelnut oil - 0:0 (no omega 3)

  • Almond oil - 0:0 (no omega 3)

  • All coconut oils - 0:0 (no omega 3)

coconut-oil-healthy-cooking-oil

Total Fatty Acid Profile (approximate)

Here’s the total fat profile of each oil so you can see their strengths and weaknesses.

High in omega 9:

  • Hazelnut oil - 78% omega 9, 16% omega 6, 5% saturated, 1% omega

  • Macadamia oil - 75% omega 9, 15% omega 7, 10% saturated

  • Olive oil - 75% omega 9, 10% omega 6, 15% saturated

  • Avocado oil - 70% omega 9, 15% omega 6, 15% saturated, 1% omega 3

  • Almond oil - 70% omega 9, 22% omega 6, 8% saturated

  • High-oleic sunflower oil - 65% omega 9, 25% omega 6, 10% saturated

  • Expeller-pressed canola oil - 61% omega 9, 21% omega 6, 10% omega 3, 8% saturated

  • Peanut oil - 55% omega 9, 25% omega 6, 17% saturated, 3% omega 3

  • Red palm oil - 45% omega 9, 45% saturated, 8% omega 6, 2% omega 3

  • Sesame oil - 42% omega 6, 40% omega 9, 15% saturated, 3% omega 3

High in omega 6:

  • Safflower oil - 74% omega 6, 15% omega 9, 10% saturated

  • Sunflower oil - 70% omega 6, 20% omega 9, 10% saturated

  • Grapeseed oil - 65% omega 6, 23% omega 9, 11% saturated, 1% omega 3

  • Hemp seed oil - 55% omega 6, 25% omega 3, 10% omega 9, 10% saturated

  • Sesame oil - 42% omega 6, 40% omega 9, 15% saturated, 3% omega 3

High in omega 3:

  • Flax seed oil - 65% omega 3, 14% omega 9, 13% omega 6, 8% saturated

  • Hemp seed oil - 55% omega 6, 25% omega 3, 10% omega 9, 10% saturated

High in saturated:

  • Refined coconut oil - 90% saturated, with an increased amount (up to 95%) medium chain triglycerides

  • Unrefined coconut oil - 88% saturated (50% lauric acid), 10% omega 9, 2% omega 6

  • Palm/palm kernel oil - 80% saturated, 10% omega 9, 10% omega 6

  • Ghee - 63% saturated, 29% omega 9, 4% omega 6, 4% trans

Flavor Profile

Once you’ve eliminated unsafe or less nutritious cooking oils, there are usually still several options to choose from. This is the fun part! You can select whichever oil tastes best to you, or whichever one coordinates best with your recipe. I’ve provided a few examples below, but let your imagination run wild.

healthy-cooking-oil

What flavor goes best?

Light sesame oil is stable for pepper and onion stir-fry, and is delicious as a drizzle on a cabbage and bell pepper salad. Toasted sesame oil makes a lovely flavor addition to broth-based soups.

Avocado oil is perfect for frying latkes, sweet potato fries, and coconut-fried chicken or fish. It also tastes delicious in homemade mayonnaise.

Olive oil makes a delicious vinaigrette dressing, and is also excellent drizzled on roasted potatoes with rosemary or used with sea salt to coat popcorn.

Hemp seed oil can be subbed for olive oil in pesto if you want to increase the omega 3 content, and mixes well with all things chocolate.

Ghee can be used anywhere you can use butter! It’s delicious with cinnamon on roasted acorn squash or as a fat to scramble or fry eggs.

Red palm oil makes a tasty base for fish stew or mango chicken, and its rich color adds a touch of the dramatic to sauces and dressings.

Flax seed oil can be added to smoothies and smoothie bowls, raw chocolate truffles, and salad dressings.

Hopefully, you now have plenty of information so you can choose the cooking oil that is best for your recipe and health needs. If not, feel free to ask.

Now get to cooking!

~Sarah

Sarah Petty