Do NOT Cook with These Oils! — Dr. Eric Berg
Dr. Eric Berg Health Opinion Summary
Deep Frying Foods
Let’s discuss the best oil for deep frying foods.
You should probably use something healthy like vegetable oil, right? You can see these healthy vegetables here, and this one is Clover Valley, so it’s probably a beautiful farm, rolling hills in Clover where they make this vegetable oil, and it’s pure vegetable oil. It’s actually considered heart-healthy on the label. There’s just a little bit of saturated fat in here. I think it’s two grams. There’s no sugar, no trans fats, and no gluten. So, this is pretty much the best oil you should use to deep fry your food.
Actually no, this was sarcasm! We’re going to talk about seed oils and then show you something you could do regarding the deep-frying oils.
Seed oils are called polyunsaturated fatty acids. “Poly-” meaning many, “unsaturated” meaning a type of oil that is very fragile and unstable. The first thing you need to know is that when they talk about vegetable oils, they’re really talking about seed oils.
While these oil have pictures of vegetables on the bottle it is not where they’re getting the oil from. It comes from corn.
The Health Consequences of Consuming Seed Oils
Soy, canola, and similar oils are part of the ultra-processed food category. They undergo industrial processing, including heating and adding hexane, a solvent found in gasoline, resulting in highly refined, empty oils. This process allows the oils to have a long shelf life. These oils make up 25–30% of our calorie intake and are found in almost everything. When frying foods in these oils, you’re essentially frying ultra-processed ingredients in another ultra-processed ingredient. For example, deep-frying a donut in seed oil combines starch or sugar with fat, creating sticky proteins in our bodies through glycation, which clogs and makes everything dysfunctional. Similarly, deep-frying chicken involves coating it with an ultra-processed ingredient like starch, combining heat, fat, and protein, which also creates this sticky, clogging substance.
When you visit a fast-food restaurant, they reuse the cooking oil multiple times, reheating it repeatedly over several days. This process makes the food increasingly toxic. Additionally, seed oils, which are often used in these establishments, were never intended for consumption. Even back in 1865, when a process to develop seed oils was discovered, they were not meant to be eaten.
Here’s a picture of a kid who’s smoking, right? Well, the oxidative stress that occurs with smoking poisons us for about six months to a year after quitting. But when we consume seed oils, it poisons us for about three years after just one serving in cooking oil. There’s some fascinating data in the book “Basic Principles of Membrane Technology”.
These oils were never meant for fuel like other fats. The biggest damaging effect from these seed oils is what they do to your mitochondria. This is why seed oils lead to insulin resistance. From there, you can develop fatty liver, obesity, heart disease, and an increased risk for cancer. Anytime you add heat to seed oils, it creates toxicity and byproducts that cause oxidation, similar to rusting. These oils aren’t burned as fuel and get stored in the body, causing issues.
Selecting Healthier Options for Deep Frying
For deep frying, consider using other types of oil. The graph below represents the peroxidation process, showing the stages of oxidation. Soybean oil ranks highest in this process, creating many problems. Following soybean oil, in descending order, are corn oil, sunflower oil, canola oil, and olive oil.
You have various oils like olive oil, tallow, butter, or ghee that you can use for cooking. However, deep frying at high heat is generally not recommended regardless of the oil. High heat can damage oils, even those with higher smoke points like avocado oil. Avocado oil, especially the unrefined, green, cold-processed type, is better used in salads. Oils high in monounsaturated fats, like olive oil, are less likely to oxidize and offer protective factors. Coconut and palm oils may smoke more when heated. Moderate heat, stir-frying, or pan-frying are better options. Tallow and ghee are good for higher heat, with ghee being slightly better than butter. Butter is great for lower heat cooking like eggs or stir-frying vegetables. Pan frying and air frying are recommended methods, with air frying being ideal as it requires no oil. Stir-frying is also a good option.
