Dishing Out The Details:
Essentials on Fats & Oils
There is no question about it, we need to eat healthy fats to maintain good health. Fats are lipids, a category of macromolecules essential for life. It’s all about choosing the right cooking fat or oil to make that big difference. Certain fats will increase health and performance more than others, and while several oils and fats are great for you, each one needs to be treated in a different way to maximize nutrition and minimize toxicity.
There is a general understanding that fats which are solid at room temperature are referred to as fats, and fats that are liquid at room temperature are called oils. If you have ever been curious about the difference, exploring the chemical compositions of fats provides helpful tips behind the science of healthy cooking, as well as offers insight into the nomenclature!
Let’s dig into the details on how to choose the right cooking oil and fat for your meals!
All the skinny on fats!
When considering a cooking fat or oil, you should first consider smoking points. Every fat and oil has its own smoking point, which is the absolute highest temperature the fat or oil should be heated. Smoke points are the temperature in which the fat begins to break down into glycerol and free fatty acids. Heating an oil or fat beyonds the smoke point changes the chemical composition, in turn, producing toxic fumes, releasing harmful free radicals, and creating harmful carcinogens. Each fat and oil has their own unique smoke point, which you can find here.
It’s essential to recognize that all cooking fats and oils can be dangerous once they have been heated beyond their smoking point—it doesn't matter if the oil is super refined canola oil, freshly-pressed olive oil, or organic coconut oil, they are dangerous when cooked passed their smoking points! You will know when a fat reaches its respective smoke point—you’ll see the smoke! It’s probably blue and smelly, so watch out! If this happens, the safest next step is to compost your food and try again with an oil or fat more compatible for higher heat. This time, keeping in mind the smoke point of the oil or fat you’re using. Pay attention to smell and the presence of gaseous vapors.
Which brings us to a second factor to scrutinize when picking a cooking oil, to consider the percentage of saturated fatty acids. Saturated fats are more stable than unsaturated fats and less likely to oxidize, no matter the temperature. Unsaturated fats have a range of stability. For example, monounsaturated fats are more stable than polyunsaturated fats. You can see the stability of the fat when you look at it at room temperature. Fats that are solid or semi-solid at room temperature (think coconut oil, animal fats, butter, and ghee) are more saturated than those that are liquid (vegetable, nut, and olive oils).
Smoke points are determined by the number of free fatty acids (FFAs) in fats and oils-- the lower the FFA content, the lower the smoke point. Refined vegetable oils have a low FFA content, which explains why they're listed as good for high heat cooking. Now, we're certainly NOT recommending cooking with vegetable oils; their high polyunsaturated fatty acid content makes them highly susceptible to oxidation at any temperature (as we’ll explain soon). Unrefined oils generally have a higher FFA content and so they need to be treated more carefully, but our only choice to when it comes to eating healthy.
So what's a Fat? Are they different from oils?
All fats are made up of lipid compounds called triglycerides. Each triglyceride compound is composed of three fatty acid molecules connected to a glycerol molecule--a short 3-carbon chain that acts as a frame for the triglyceride. The fatty acid molecules are composed of two parts shaped like a tadpole. There is the oxygen-hydrogen “head” and a long “tail” made from a chain of carbon atoms. Each carbon atom chain has one or two hydrogen atoms attached. These fatty acid carbon tails can be anywhere between 4 to 28 carbons long, but typically between 14 to 22. The “head” of the fatty acid molecule attaches to the glycerol molecule to form the -glyceride.
Unsaturated fatty acids are slightly more complicated. In these fatty acids, the hydrocarbon tail has one or more “kink” in the chain. A kink is the result of a double or triple bond between two carbons in the chain. Consequently, each of these double bonded carbons can hold only one hydrogen. In other words, without two hydrogens, the carbon atoms are not completely filled with hydrogens, leaving them “unsaturated”. Unsaturated fatty acids can be monounsaturated with one kink in their hydrocarbon tail or polyunsaturated with at least two kinks. Due to these kinks, unsaturated fatty acids cannot pack together very tightly. Consequently, unsaturated fatty acids are liquid at room temperature. We generally refer to this oil!
If there’s one fatty acid attached to the glycerol, the compound is called a monoglyceride; if there are two fatty acids, it’s a diglyceride; three FFAs will make a triglyceride. The number of attached fatty acids is our primary point concern.
The structure of the fatty acids’ hydrocarbon tail determines whether the fatty acid is saturated or unsaturated. The term saturated refers to the carbon atoms; in which each hydrocarbon tail is ‘filled’ saturated by the most hydrogens possible. Saturated fatty acids have the simplest hydrocarbon structure with every carbon fully bonded with two hydrogens. Structurally, the saturated fatty acids will pull in together tightly, resulting in a solid fat at room temperature.
Cooking fats and oils contain different ratios of saturated and unsaturated fatty acids. We generally categorize cooking fats and oils based on whichever fatty acid is in the highest proportion. For example, fats that have a higher proportion of saturated fatty acids are generally referred to as “saturated fats,” even if they do contain some mono- and polyunsaturated fatty acids.
As we stated before, solid fats at room temperature are frequently referred to as fats and fats that are liquid at room temperature as oils, but for the sake of brevity, we’ll call everything a fat going forward.
1. Introducing Toxicity Into Your Food During Cooking
Oxidation (or oxidization) is a chemical reaction in which an atom or ion within a molecule loses an electron, giving the entire molecule an increased positive charge. When a positive charge is gained, the molecule is referred to as an oxidized agent. The free-floating electron attaches itself to the a different molecule, giving that molecule a negative charge. With the added electron, the molecule is considered oxidizing agent, and also considered to be reduced. Oxygen molecules often function as oxidizing agents, but other chemicals can perform these oxidizing agent tasks as well. While oxidization happens at a molecular level, you can see the effects of oxidation all over the place. For example, think of apple slices turning brown once the apple is cut open, this is due to oxidization. Oxidation is a natural process and it’s important to remember that oxidization is not necessarily bad.
Oxidation becomes a problem when it leads to the formation of a large number of free radicals in our food and our bodies. Free radical formation occurs when the oxidizing agent’s new electron cannot pair with another electron. The electron will hang off of the molecule and attempt to grab more electrons off of other surrounding molecules. This process sets off a chain reaction of electrons being grabbed from surrounding molecules, which all become charged.
Free radicals occur naturally in our bodies as part of essential metabolic processes and as a result of external sources, like environmental pollutants, certain medication, and some food cooking methods. Free radicals are not inherently a problem. However, a build-up of these highly reactive atoms and molecules can lead to unwanted cell damage and cell death. When the body is overwhelmed by too many free radicals to safely regulate them, oxidative stress ensues. Which in turn causes malfunctions to other essential biological components and processes that can trigger inflammation, atherosclerosis, cancer, and other diseases.
Different types of fats are more or less prone to oxidization. As we mentioned above, the total number of saturated fatty acids is important for the stability of a fat.
Fats have both unsaturated and saturated fatty acids, but when the fat has more saturated fatty acids than unsaturated, it is more structurally stable at any temperature and less to oxidize. On that same note, the less saturated the fat, the less stable it is. Additionally, oxidation is more likely.
The kinks in the hydrocarbon tails of unsaturated fats also make fats even less stable. At each kink, the bond between the hydrogen and carbon is highly reactive and itching to get rid of an electron. The more kinks there are in a hydrocarbon tail, the more opportunity there is for reactivity. So, monounsaturated fats (fatty acids with only one kink) are less susceptible to oxidation than polyunsaturated fats (fatty acids with at least two kinks). Moreover, fat oxidization happens slowly at room temperature (after repeated oxidization, the fat becomes rancid), or more rapidly when the oils are heated since heat is a catalyst for chemical reactions.
Which brings us to the next topic: heat. Using heat is great! But, certain methods of heating fats negatively impact your health and performance more than others. Heat is incredibly important to consider because this is a step where toxicity can be introduced to your well-sourced fat. In order to cook fats safely, you need to pay attention to two things: the type of oil you’re using and the temperature to which you’re heating it. As you’ve probably figured out, it is much safer to heat saturated fats than unsaturated fats. (There are many other reasons to avoid most unsaturated fats, which we’ll go into below.) The only fat we use in the kitchen that is not mostly saturated is olive oil, but we never apply heat to it.
Each fat has its own threshold of safety, and that threshold is linked to its smoke point
Delving Deeper into Smoke Points:
Before we dig deeper into smoke points, recall from above that a fat’s smoke point is the temperature at which the fat begins to give off carcinogenic, smelly smoke. Once a fat reaches its smoke point, the fat’s nutritive value begins to degrade and oxidization occurs rapidly. When there are more polyunsaturated (contains at least two double bonded carbon kinks) fatty acids in a fat, there is a greater chance of oxidation when the smoke point has been reached. And remember, all fats have their own unique smoke point!
Smoke points are determined by the number of free fatty acids (FFAs) in a fat; the lower the FFA content, the lower the smoke point. Unrefined oils generally have a high FFA content and have a high smoke point. Whereas, refined polyunsaturated vegetable oils (or PUFAs) have less free fatty acids and a lower smoke point. PUFAs are generally characterized by their lightly colored various soybean oil (or what is commonly called vegetable oil), canola oil, corn oil, sunflower oil, and safflower oil. Because of their low FFA content, they're listed as a good oil for high heat cooking. However, this is where we invite well-intentioned skepticism, just because the packaging says PUFAs are safe to use!
Polyunsaturated vegetable oils have two classifications: omega-6 and omega-3. Our bodies need both classifications and omega-6 in significantly less amounts. Excess consumption is actually harmful to our bodies. Most fats have both types of classes, just the ratios between omega-6 and omega-3 vary among different fats. However, even though we don’t need omega-6 to the same degree, the general U.S. population is beginning to consume it at much higher rates. One reason we are consuming more omega-6 is because of the PUFAs that stock even the smallest, healthiest grocery store shelves. you see all contain a high amount of omega-6 fatty acids.
One of the major issues with omega-6 fats is the linoleic acid (LA) that composes the fatty acid. LA is also necessary to include in our diets, but only in very small amounts. People cannot synthesize LA fatty acids on our own so must consume them for essential biological processes. This is another case of too much intake; most people get between 4 and 10% of their daily calories from these oils. That is simply way too much linoleic acid!
Oxidized LA fatty acids are also found in oxidized low-density lipoprotein (LDL) cholesterol. When found in large amounts in the body, LDL cholesterol is a major culprit in atherosclerosis, a disease from the buildup of plaque in the arteries. When plaque builds up, the arteries become hard, narrow, and restrictive to oxygen and blood pathways. The consequences are very serious and can result in heart disease and stroke. Another issue caused by fats with higher levels of LA fatty acids than healthier unsaturated fats (omega-3s) is inflammatory responses. A pro-inflammatory environment and could potentially interfere with neurological functions.
Linoleic acid’s molecular structure is particularly prone to oxidization. The results can be dangerous if linoleic acid oxidizes. When high LA oils oxidize, they create several noxious compounds. Some of these, 9- and 12-hydroxy-octadecadienoic acid (9- and 12-HODE for short) and 9- and 13-oxo-octadecadienoic acid (9- and 13-oxoODE for short) are associated with cardiovascular disease and chronic pain. The biggest culprits, though, are the OXLAMs (or oxidized LA metabolites). They have been shown to be elevated in patients with Alzheimer’s disease and non-alcoholic fatty liver disease—so much so that they’re actually used as predictive tools for scientists to identify patients at high risk for the disease.
If you need any more convincing to ditch those industrial vegetable fats, keep in mind that they’re simply not good sources of nutritive value. They may be calorie-rich, but they’re nutrient-poor. Plus there are not any well-designed studies that prove that unsaturated fats are actually better for your heart.
Choosing the right fats
Whew, that was a lot of information. I’m sure by now you’re asking what does it mean for my health?
The good news is that there are many great choices for you to pick from when it’s time to cook with fats. Let’s start with the fats that should get frequent use in your kitchen: the saturated fats.
Medium-chain triglycerides (MCT) or medium-chain saturated fats should be eaten in frequent consumption. These are the primary fats in breast milk, so you know they must be good for you, as imperative growth depends upon them! Unlike long-chain triglycerides, MCTs are not absorbed in the lymphatic system. Instead, they are broken down in the liver, where it can be used for energy rather than put into fat storage and because MCTs are smaller molecular chains than LCTs, they require less salt bile and pancreatic lipase to break them down. This results in faster and more complete hydrolysis. They are quick to be absorbed into the bloodstream where the body can use them right away. Due to their easily digestible nature, they are given to patients with malabsorption disorders.
There are a range of health benefits that medium-chain saturated fats provide to the body. The liver breaks down MCTs into medium-chain fatty acids (MCFAs), where they are converted into ketone bodies. Ketones are are water soluble organic compounds that are then released into the bloodstream, providing a source of fuel for the brain and body. The brain is fueled by glucose but degenerative brain diseases are commonly affected by a lack of absorption of glucose. Studies have shown that MCTs have been shown to improve mild cognitive impairment, dementia, and Alzheimer’s, diseases which are impacted by the brain’s inability to use glucose by alternatively being able to intake ketones as fuel.
MCTs are classified by their carbon length which ranges between 6 to 12. There are four kinds of MCTs, depending on how many carbons make up the hydrocarbon tail. Each of the types are broken down easier than LCT and are used as a quick source of energy.
At 12 carbons long, the MCT is referred to as lauric acid, which has antibacterial, antiviral, and antioxidant properties, and promote the development of ketone bodies. Three other compounds naturally occur in MCTS are caproic acid with 6 carbons (C6:0), caprylic acid with 8 carbons (C8:0), and capric acid with 10 carbons (C10:0). Additionally, when the MCT is composed to 8 carbons, it is caprylic acid. Caprylic acid has antimicrobial properties that help out the guy. Capric acid is a longer medium-chain triglyceride and will take longer to turn into energy, but is more abundant than caprylic acid in coconut oil.
Coconut oil, in particular, is a great cooking fat because it is about 60 percent MCT. It is quick and abundant source of MCT and is far less vulnerable to oxidative damage than other cooking fats, lowering the risk of introducing toxins during the cooking process.
The Specifics: Where You Can Find Healthy Fats
Long-chain saturated fats are particularly beneficial for keeping up good health. As you may recall from our discussion on fat structures, the molecular structure of a fat consists of an oxygen-hydrogen ‘head’ and a hydrocarbon ‘tail.’ Long-chain saturated fatty acids have a particularly long tail. There are different kinds of long-chain saturated fats, with the most common called myristic, palmitic, and stearic. These types of fats can be primarily found in dairy products and the meat of ruminant animals (beef, lamb, and pork). In smaller quantities, they can also be found in coconut and egg yolks. Rendering you own tallow from beef or lamb fat, lard from pork, schmaltz from poultry fat (including duck fat) is an excellent source of healthy fats. Utilizing as many parts of an animal as possible is both beneficial and sustainable. Just remember to render fats from organic pasture-raised animals to keep your fat source nutrient-rich, GMO and grain-free! Otherwise, you risk a high intake of omega-6, throwing off a healthy ratio of omega-6 to omega-3s.
Long-chain saturated fats are the primary storage form for energy in humans. In fact, they form the core structure of 75-80% of our fat cells. These fats help to incorporate calcium into our bodies, protect the liver from toxins like alcohol and acetaminophen (the primary ingredient in Tylenol), deliver fat-soluble vitamins (A, D, K, E) to the bloodstream, support a healthy immune function, and regulate the availability of helpful polyunsaturated fatty acids like omega-3s--which we will come back to.
Recent studies report saturated fats are actually highly beneficial for the body and heart, despite outdated research formally declaring saturated fats as bad for heart health. Indeed, research shows that saturated fats can actually increase the ‘good’ kind of cholesterol (high-density lipoprotein, or HDL) cholesterol) which helps transport fat molecules around the body. Saturated fats have also been shown to reduce the formation of lipoprotein(a), an inflammatory substance that is considered a risk factor for atherosclerotic diseases like coronary heart disease and stroke. Furthermore, they help make LDL cholesterol larger, more buoyant, and less likely to cause problems.
On the other hand, unsaturated fats are the pesky worrisome fats. Unsaturated fats appear in three different forms: as monounsaturated fatty acids, polyunsaturated fatty acids, and trans fatty acids. Despite the dangers we mentioned above regarding industrial polyunsaturated fats, each of these types of unsaturated fats (including certain natural trans fats) plays an important part in any diet.
Monounsaturated fats (like oleic acid) should be eaten more abundantly than polyunsaturated fats. Found in olives, avocados, eggs, poultry fat, almonds, macadamia nuts, and lard, they’re a tasty, relatively stable choice. While cooked eggs, poultry fat, and lard are safe when cooked at low- to medium-temperatures, we believe that vegetable-based monounsaturated fats shouldn’t be heated at all. (See below for more information on olive oil.)
When prepared properly, monounsaturated fats help to reduce LDL cholesterol and increase HDL. They also help prevent oxidation and inflammation in the body, lower blood pressure, and help to prevent the formation of blood clots. The only caveat to eating monounsaturated fats from nuts is that they contain fairly significant amounts of linoleic acid (LA, see above), which is inflammatory in high amounts. When eaten with plenty of omega-3s, the excess LA isn’t a problem.
Speaking of omega-3s, they are some of the most important polyunsaturated fats for us to eat. There are 3 primary types of omega-3 fatty acids: ALA, which is the primary (shortest-chain) version of omega-3 and is found in walnuts and flax seeds; and EPA and DHA, which are longer-chain versions of omega-3 and are both found in seafood. ALA isn’t particularly helpful on its own, but it is a precursor to both EPA and DHA, and these two omega-3s are crucial in protecting our bodies against inflammation. The best way to get these long-chain omega-3s is to eat whole seafood; fish oil contains omega-3s as well, but is prone to rancidity and oxidation.
Omega-6 fatty acids are the second form of polyunsaturated fats found in our diets. They are also crucial to our bodies’ function, but most Americans already eat them in abundance (see above regarding industrial PUFAs). Like omega-3s, there are longer and shorter chain omega-6 fatty acids. The shortest chain, linoleic acid, is the primary fat in the industrial vegetable oils we discussed above. The most common long-form of omega-6 is called ARA, which is present in most animal foods. We need it to mediate cell signaling in the body and to help form lipoxins, which trigger the release of anti- inflammatory compounds that are synthesized from EPA and DHA. ARA is also abundant in our brains and is said to help to relax blood vessels.
The key with polyunsaturated fats is to have a proper balance between omega-3s and omega-6s. Too much omega-6 with too little omega-3 can lead to inflammation, but you can’t eliminate omega-6 altogether. As you may have interpreted above, both omega-6s and omega-3s are dependant on each other to combat inflammation. Most studies agree that a ratio of around 1:1 omega-6 to omega-3 leads to the best results.
In addition to the above-mentioned fats, omnivorous diets that include grass-fed meat will inevitably include some trans fat—but it’s far from the industrially produced trans fat that has been systematically outlawed in fast-food restaurants and processed foods. Instead, we’re talking about natural trans fats called CLAs. Any good grass-fed beef will include small amounts of this type of fat, which is totally normal and surprisingly beneficial. CLAs have been shown to be inversely associated with heart disease, to improve glucose tolerance and insulin sensitivity, to help block the growth and spread of tumors by reducing inflammation, and to potentially help reduce body fat. Of course, you wouldn’t go out and buy a jar of CLA fatty acids—they come right along inside grass fed beef.
The following charts provide a quick breakdown of the make-up and the smoke points of different cooking fats. You’ll notice that while there is a wide range in smoke points of both the good and poor choices, almost all of the oils listed as “good choices” all have a very high saturated fat content relative to the other fatty acids. This saturated fatty acid content is key. So when choosing cooking fats, it’s important to pay attention to both the fatty acid content first and the smoking point second. The less polyunsaturated fatty acids, the better! (Note: each temperature is approximate; every brand of oil will vary a little bit.)
Why not cook with olive oil?
High-quality, fresh, extra-virgin olive oils certainly have a lot going for them: they’re monounsaturated and therefore less reactive than polyunsaturated fats, they have a very low FFA content, and they contain a high level of polyphenol antioxidants. However, this standard is inconsistent across brands and even olive varieties. Some of the freshest oils, like olio nuovos, contain particulate matter that can burn quickly and bring the smoke point down (just like the milk solids in butter). The science is also out on how much heating changes the nutritional profile of the oil. Even from a taste perspective, heating olive oils too much can change and mute the flavor of the oil. When it comes down to providing the safest and most helpful food to our customers, we simply don't want to take the risk of heating olive oil. It's most flavorful and nutrient-dense when raw, so that's how we use it.
So what oils should be used for cooking? Here are our favorites, plus some tips and suggestions for using them in the kitchen:
Avocado oil: Avocado oil can be used as a great marinade for meats or salad dressing. More refined avo oil can be used for low temp cooking, but be sure not to heat it above the smoke point, listed at 375 degrees.
MCT oil: Medium-chain triglycerides are more easily digestible than long-chain triglycerides, providing a great source of energy. There are a few different brands that have come up with their own versions of MCT oil. We personally love and trust Brain Octane by Bulletproof--serve it cold like in your salad dressing or mix it with oil for cooking, but be careful to not heat above 320℉.
Coconut oil: Safe for cooking at medium to medium-high temperatures. We use coconut oil to enrich vegetables that we want to keep dairy-free, like in our vegetable meatballs and as a spread on Yucan Crunch crackers. Coconut oil is also a fabulous body product—it’s great for the hair and skin!
Ghee: When cooking at medium to medium-high temperatures, ghee is great! Ghee is clarified butter with roots in Indian cuisine. We use unflavored ghee in soups and stews and spread infused ghee on Yucan Crunch. Note: When on a quest for ghee, make sure it’s pasture-fed!
Rendered animal fats: Tallow (beef fat), lard (pork fat), and schmaltz (chicken fat) are all safe at medium to medium-high temperatures. We use them in meat sauces, soups, and especially meatballs!
Butter: Butters should be used at low temperatures. We add it to soups and vegetables that we’re cooking slowly and with low heat, or to finish a dish with an extra dose of richness.
Extra-virgin olive oil: We think olive oil is best used in a raw state, like in salad dressings or as a finishing oil for soups and herb filled sauces. Why only use it raw? High-quality, fresh, extra-virgin olive oils are great; they’re monounsaturated and therefore less reactive than polyunsaturated fats; they have a very low FFA content; they contain a high level of polyphenol antioxidants. However, this standard is inconsistent across brands and even olive varieties. Some of the freshest oils, like Olio Nuovos, contain particulate matter that can burn quickly and bring the smoke point down. Simply from a taste perspective, heating olive oils too much can change and mute the flavor of the oil.