Which Cooking Oils are Healthiest?

Have you ever walked down the grocery store aisles and become overwhelmed with all of the different cooking oils you could use to prepare your dinner? You may have heard that it’s important to choose healthy sources of fat, but it can get a little confusing because there are so many different options (and opinions) out there! I get a lot of questions about what oils/fats are healthiest or best to use when cooking, so today I’m going to break it down for you as simply as possible.

Oils are considered fats, which play an important role in our health. Fats are one of the main macronutrients our body needs to function (carbohydrates and protein are the other two). They are a source of energy and carry fat-soluble vitamins (vitamins A, D, E, and K) that are important for a number of vital functions, including growth and development.

A quick chemistry lesson for the science nerds like me:

Chemically, fats are made of long chains of carbon bonded to hydrogen called fatty acids. There are four different kinds of fatty acids: saturated, monounsaturated, polyunsaturated, and trans fats.

Saturated refers to fatty acids that have all single bonds between the hydrogen and carbon molecules, so sources of fat that are mostly saturated will typically be solid at room temperature.

Unsaturated fatty acids have both single and double bonds between their carbon molecules, which means sources that are primarily unsaturated fat are liquid at room temperature.

Monounsaturated fats have a single double bond in their carbon chain, whereas polyunsaturated fats have multiple double bonds.

Trans fats are a type of unsaturated fat found in very small amounts in nature, but artificial trans fats became widespread in our food system as a way to make vegetable oils solid at room temperature (just like saturated fats). They’re a cheap way to make foods taste good (think fried foods, baked goods, and packaged snacks), but have been linked to heart disease and should be avoided. Partially hydrogenated oils, the main source of trans fats in our food system, were banned by the FDA in 2018, so avoidance is much easier than it used to be.

I think a common misconception is that most oils or cooking fats are either one type or the other, but the reality is that no fat is purely saturated or unsaturated fatty acids – fats are a combination of many different fatty acids. It’s the ratio that makes a difference when we’re talking about uses and health benefits.

So, let’s take a look at some of the most common cooking oils you’ll find:

Note: There are MANY oils beyond what I’m going to mention below, but these are what I would consider “staples” in most households or ones that clients commonly ask me about. Thought they aren’t mentioned, I’m also a fan of oils such as sesame, flaxseed, walnut, etc. because of their unique flavor profiles and benefits, but we’re not going to get into that with this article. However, definitely let me know if you have questions about other oils, and I’d be happy to do a follow-up post!

Olive Oil

Olive oil is one of the most commonly recognized heart-healthy oils, and for good reason. A staple of the Mediterranean Diet, it has been associated with a lower incidence of chronic heart diseases [1]. The health benefits of olive oil are due to its primary make up of monounsaturated and polyunsaturated fatty acids. Unsaturated fats (particularly omega-3 fatty acids) and antioxidants found in extra virgin olive oil have been shown to reduce LDL (or “bad”) cholesterol and increase HDL (or “good”) cholesterol, as well as decrease triglycerides, blood pressure, and inflammatory markers [2] – all great things for our overall health!

There are a few differences between extra virgin olive oil, virgin olive oil, and refined olive oil – this article breaks down these definitions really well. They’re pretty interchangeable in most recipes, but I prefer extra virgin olive oil for its flavor and the extraction process used (plus extra virgin olive oil will confer the most health benefits – refined will have the least).

Recommended uses: Sautéing, roasting under 400ºF, finishing dishes, salad dressings, marinades, cooking with moderate heat

Sam the Dietitian says: This is a regular staple in my pantry, and an oil I would definitely consider health-promoting! When in the kitchen, extra virgin olive oil is probably what I’m reaching for the most.

Canola Oil (and Other Vegetable Oils)

Canola oil primarily contains monounsaturated and polyunsaturated fats, which has long led to it being categorized as a healthy choice. However, recent concerns about canola oil have be raised, given that it is a refined, bleached, and deodorized oil (RBD for short). Canola and other vegetable oils also have a higher amount of omega-6 fatty acids than omega-3 unsaturated fatty acids. While it’s good to have both, the majority of Americans consume WAY more omega-6 than omega-3, so it’s good to limit it when you can [3].

Recommended uses: Roasting, high heat cooking, deep frying, baking

Sam the Dietitian says: Canola oil is something I’m personally a little bit on the fence about given how it is processed and that it’s higher in omega-6 fatty acids (when most of us need to increase the ratio of omega-3 we’re consuming). However, you may be surprised to hear that it’s something I still keep on hand. It is an inexpensive oil with a neutral flavor and high smoke point, so when I need to sear something, want to bake, or want to heat my Trader Joe’s Mandarin Chicken so it’s nice and crispy (if you know, you know) – it’s my preferred oil. Recent systematic reviews have continued to support that canola oil has a beneficial effect on LDL cholesterol [4], so I’m not counting it out completely. I believe it can have a time and place, but I try to use other oils the majority of the time.

Coconut Oil

Coconut oil has gained recent popularity as a common cooking oil thanks to social media. One of my favorite memes (source unknown) reads:

Frizzy hair? Coconut oil.
Dry skin? Coconut oil.
Bad credit? Coconut oil.
Boyfriend acting up? Coconut oil.

Clearly, coconut oil has been made out to solve all of our problems, including those related to our health. It’s believed to support health due to its content of medium chain triglycerides (MCTs), which seem to be easily used by our bodies. This is because MCTs can diffuse directly to our portal system (aka blood stream) from our gastrointestinal system, meaning they bypass parts of normal digestion. Our bodies are able to use MCTs more quickly for energy than most other fats. However, coconut oil is primarily saturated fat. A meta-analysis published in 2020 examined 16 different studies on coconut oil and found that coconut oil significantly raised LDL cholesterol (the not so good kind) when compared to other non-tropical vegetable oils [5].

Recommended uses: Medium heat cooking and baking under 350ºF, adding coconut flavor to a recipe, rubbing all over your life

Sam the Dietitian says: Classic dietitian line here, but everything in moderation! Coconut oil can add awesome flavor to a dish or be wonderful in baking. However, because it is a saturated fat, it shouldn’t be the only oil you rely on, and it isn’t a panacea for health.

Avocado Oil

The use of avocado oil is on the rise as well, and it’s no surprise that we’ve found different ways to show our love for this awesome fruit besides putting it on toast! Avocado oil is about 70% oleic acid, a monounsaturated fat also found in olive oil that is linked to supporting heart health.

Recommended uses: High heat cooking (smoke point is 375-400ºF), salad dressings, sautéing, roasting veggies

Sam the Dietitian: Avocado oil is another pantry staple for me because it’s SO versatile and high in unsaturated fatty acids. The flavor is pretty neutral, and I’ve found that it compliments most of the things I cook really nicely. Avocado oil is one the pricier side, so if that is a barrier to you, olive oil has similar benefits (you’ll just need to pay attention to your cooking temperatures).

Bonus: Butter and Ghee

Though they aren’t technically oils, I wanted to also include butter and ghee in this post since I’ve been asked if butter is “healthy” again and ghee seems to be a new trend (in part thanks to the rise in popularity of Indian cuisine and Ayurveda in the US).

Butter is a dairy product made by churning milk and then separating the solid fats from the liquid. Ghee is clarified butter that is made by heating regular butter and separating out the milk solids again, but this time you’re saving the liquid, which you then let solidify and cool into the ghee. Because more of the milk proteins are removed when making ghee, it may be more tolerable to people who are sensitive to dairy.

Both butter and ghee are higher in saturated fat, even though they may contain some beneficial nutrients and other fatty acids. As I mentioned before, saturated fat has been linked to an increase risk of heart disease, so it’s better to limit the amount of saturated fat you consume. This can easily be done by using a wide variety of fats and oils in your cooking.

TL;DR: IT’S OK TO USE BUTTER! It’s not a health food, but it may be what makes a meal satisfying to you. Switch up your sources of fat and you’ll be a-ok!

The Bottom Line

I encourage the majority of my clients to aim for consuming more unsaturated fats (oils) than saturated fats, because replacing saturated fats in the diet with unsaturated fats has been linked to reduced risk of heart disease (citation).

However, I think it’s important to remember that when it comes to cooking, different fats may be preferred depending on their flavor or smoke point (the temperature at which an oil begins to burn/smoke). If you’re cooking with high heat, please choose an oil such as avocado or canola oil so that you stay well above the smoke point.

When cooking, you also aren’t typically using enough of a fat for it to have a drastic effect on your health, so use what imparts the flavor you’re looking for and matches your cooking temperature. Using a variety of oils that fit your flavor and cooking needs will help you maximize the potential benefits each holds. Butter is dang delicious on veggies, and if it gets you to eat them, go for it! Also keep in mind that you don’t need to fear fat – it’s extremely important for our health and helps us absorb vitamins and minerals from our food in addition to making it taste great.

At the end of the day (and as I always say), one food isn’t going to make or break your health – consuming a less healthful oil on occasion won’t be your undoing. It’s your overall eating pattern that matters!

If you are someone experiencing or at risk for cardiovascular disease, I recommend working with a registered dietitian to figure out what will be best for you based upon your lifestyle and other health habits. If you want to work with me as your dietitian, apply for nutrition coaching here.

Mindfully yours,
Sam

Sources

1. Guasch-Ferré, M.; Hu, F.B.; Martínez-González, M.A.; Fitó, M.; Bulló, M.; Estruch, R.; Ros, E.; Corella, D.; Recondo, J.; Gómez-Gracia, E.; Fiol, M.; Lapetra, J.; Serra-Majem, L.; Muñoz, M.A.; Pintó, X.; Lamuela-Raventós, R.M.; Basora, J.; Buil-Cosiales, P.; Sorlí, J.V.; Ruiz-Gutiérrez, V.; Martínez, J.A.; Salas-Salvadó, J. Olive Oil Intake and Risk of Cardiovascular Disease and Mortality in the PREDIMED Study. BMC Med., 2014, 12, 78.
2. Nocella, C.; Cammisotto, V.; Flanchini, L.; D’Amico, A.; Novo, M.; Castellani, V.; Stefanini, L.; Violi, F.; Carnevale, R. Extra Virgin Olive Oil and Cardiovascular Diseases: Benefits for Human Health. Endocr Metab Immune Disord Drug Targets., 2018, 18, 1.
3. Simopoulos, A. The Importance of the Omega-6/Omega-3 Fatty Acid Ratio in Cardiovascular Disease and Other Chronic Diseases. Exp Biol Med., 2008, 233, 6.
4. Schwingshackl, L.; Bogensberger, B.; Bencic, A.; Knuppel, S.; Boeing, H.; Hoffman, G. Effects of oils and solid fats on blood lipids: a systematic review and network meta-analysis. J Lipid Res., 2018, 59, 1771-1782.
5. Neelakantan, N.; Hoong Seah, J. Y.; van Dam, R. M. The effect of coconut oil consumption on cardiovascular risk factors: a systemic review and meta-analysis of clinical trials. Circulation., 2020,