Does it Matter What Oil I Cook With?

In short, the answer is yes.

What oils you cook with make a huge difference, even at the tiny molecular level.

I'm sure you've heard a decent bit about oils. Butter is the new margarine. Coconut oil is the new butter. Avocado oil is the new coconut oil.

Diving beyond the trends, in this blog I'm going to break down the science for you so you can know which oils to cook with and why.

What is the makeup of edible oils?

The main component of edible oils are Triglycerides. A Triglyceride is one part Glycerol, three parts Fatty Acids. For the purposes of this blog, we are most interested in the Fatty Acids.

Fatty Acids

Fatty Acids are the part of the oil that are going to tell us how the oil behaves when heat is applied.

We are going to look at three types of Fatty Acids.

1. Saturated Fatty Acids

2. Monounsaturated Fatty Acids

3. Polyunsaturated Fatty Acids

You may have seen these on a nutrition label before. They are the little subcategories under Fat, and usually just go by their first names, Saturated, Monounsaturated, and Polyunsaturated.

Saturated Fatty Acids (SFAs)

These babies have a pretty bad reputation. We'll ignore their reputation and get to the facts.

Let's personify SFAs.

SFAs are really loyal and stable people. They form really close relationships with other SFAs, and their relationships are so close and strong that it's almost impossible to break them up. When one group of SFAs meets another group of SFAs, they are immediately really close and loyal to each other. They stick together through thick and thin, even when circumstances get extreme.

Scientifically speaking, SFAs are chains that are connected entirely by single bonds and are completely saturated with hydrogen, causing them to be very stable. This allows them to stack together very tightly, which makes it hard to break them apart, even at high heat.

Monounsaturated Fatty Acids (MUFAs)

MUFAs, for the most part, are loyal and stable people. They form strong and happy relationships, but there's always that one person in the group that causes problems. That one person causes a kink in the group, and can make it hard to get super close to other groups. They stick together for the most part, but when things get too extreme, the group breaks up.

Scientifically speaking, MUFAs are chains that are almost entirely connected by singles bonds, and are almost completely saturated with hydrogen. MUFAs are fairly stable. The chains have one double bond, which means there is one less hydrogen in the chain. This kinks the chain, and this kink causes the chain to break at high heat - medium and low heat do not break MUFAs.

Mono means one, so it makes sense that in MUFAs there's one double bond, or one trouble maker in the group.

Polyunsaturated Fatty Acids (PUFAs)

Let's be real. PUFAs are pretty flaky, unstable people. They form fun relationships together, which can be healthy if everything in life is going smoothly, but they aren't very loyal or committed to the group. There are multiple people who are selfish and cause kinks in the group. When circumstances get extreme, they easily break up.

Scientifically speaking, PUFAs are chains that have multiple double bonds, and are not very saturated with hydrogen. This causes them to be unstable. There are multiple kinks in the chain, allowing any heat easily to easily break PUFA bonds.

Poly means many, so it makes sense that there are many double bonds, or many trouble makers.

Tying it all together

When it comes to cooking, it's best to use oils that have the fatty acids that can withstand heat.


When fatty acids break apart, they oxidize. This oxidation leads to free radicals. Free radicals wreak havoc on the body. They are unstable, reactive molecules that are missing an electron. They steal electrons from healthy cells in the body, which causes those cells to undergo cellular damage. This is correlated to aging skin, disease, and cancer development.

Which of the three fatty acids can withstand heat the best?

Saturated Fatty Acids!

When it comes to cooking at high heat, use oils high in SFAs!!

SFA examples: Coconut oil, ghee, butter

If you are going to be cooking at medium heat, oils high in MUFAs are also a great choice if you're trying to reduce saturated fat intake. The oils I list below have a good Omega 3: Omega 6 ratio, but ohhh that's a whole other topic!

MUFA examples: Olive oil, avocado oil, macadamia oil

It's best to stay away from oils high in PUFAs when cooking. They are too unstable and cause to much damage.

PUFA examples: vegetable oils, many nut oils, many seed oils, soybean oil

Wooooooof. That's, like, a lot of the oils that are used in everything. Yes. I know. Check your food boxes on the shelf, check your chip bags, check anything processed. They will have at least one of these oils. Once these oils are heated, they are dangerous. Of course, you feel tired and bloated after eating processed foods, the oils they are prepared with release an army of free radicals in the body!

Friends, to sum it up, avoid cooking with oils high in PUFAs. You can tell if any oil is high in PUFAs by looking at the nutrition label on the bottle. Under the category Fat, see if there are Saturated fats, Monounsaturated fats, or Polyunsaturated fats. If it’s high in Polyunsaturated fats, don’t heat it or cook with it! Use the oils that have stronger bonds, like coconut oil, ghee, or olive oil. And be sure to check the ingredients list on your processed foods to avoid consuming the heavily refined oils high in PUFAs (or just avoid processed foods :).

You'll feel the difference.

With much love,